GB2337266A - Isocyanate-based rigid foam and process for making isocyanate-based rigid foam also stable polyester polyol compositions. - Google Patents

Abstract

A process for producing a rigid isocyanate-based foam comprises the steps of reacting an organic and/or modified organic polyisocyanate with a polyol composition and, optionally, with a relatively low molecular weight chain extender or crosslinker in the presence of a catalyst. Auxiliaries and/or additives may also be included in the reaction mixture. The polyol composition comprises a phthalic anhydride-initiated polyester polyol, a blowing agent comprising a C 4 -C 6 hydrocarbon, and a fatty acid or fatty alcohol ethoxylate compatibilizing agent. The blowing agent is soluble in the polyol composition, thereby reducing the risks associated with the use of such blowing agents in the manufacture of rigid polymer foam articles and enabling the production of rigid foam having good dimensional stability and improved insulation properties. The stable polyester polyol composition and the isocyanate-based rigid foam are also claimed as such.

Description

ISOCYANATE-BASED RIGID FOAM AND PROCESS FOR ING ISOCYANATE-BASED RIGID

FOAM, ALSO STABLE POLYESTER POLYOL COMPOSITIONS 2337266 The preg;ept invention relates generally to isocyanatebased rigid foams, to stable polyester polyol compositions useful in making them and to a process tor making isocyanate-based rigid foams from stable polyester polycl compositions comprising a phthalic polyeste- polycl, a C4-C6 hydrocarb= blowing agent, and a compatibilizing agrent having an = ot from Offitt 7 to 12. The compatibilizing agent is a fatty acid or fatgr-,alcohol et-hoxyiate. The blowing agent Is soluble in the polyo:t,-CS-4t-4on. The process comprlsas reacting an organic poly:Lsoctt with the polycl compositior. in the pzese=e of the blowing at and other optional components ". - The process results in a riqid-polyu-"ethzze/poly-socyw.u=ate foam which has improved d.,maw4' Stability and thexmal insulation properties i=luding improvadg]t-f actors.

Eydroca.rbo=3 are wid-'- captance as viable alte=,at..bve biow4-:lg agents -4" the manufaoWe of rigid polywati=e!oarn-.z.

Duc to the =.zn-pola-- hydrophc clla--acte--4-s-.-4c od- hydrocarbons, they a=c only partially so!^, if not. C=. l=soluble, in many pclycls used to mar-ulact rigid po-',y=athane f cams. The or poor shelf lls:--f M:1Xt.= as has, to date, limited the abl of stc-.m.g hatches of the mix:u=es for use at a later Due to tl,.e poor solubility 0:0 hyd--oca--bons blowing agents IW- Volycls, the blowing age=t must be added to tis pclyol under constant i=ed.,ate-ly before dispensin I.Ocam,i:g th=ouga a mixhaad. The poor solubility 0-hyd--oca=.bms also tends to!cad to coarser. or U.".evan-call structwas in a resultant pcly%=et!iane foam. As is wall, t1Se the--..a-l conductivity of _ poor cell strac,-=e. Tie=e,0.0re, a fcam generally increases WiWA it is critical that hydrocazc un-,-form-ly d-4spe--sed u---de- -AL co=ra.-,-t agitation throu poly-01 MLX-t..1-,e -;r=adiately pr-,or to foaming in order to in a rigid pciywetha=a fcam ha-ning the des-,red tbLermiLl lation values.

in- U.S. Patent No. 5.391,31711- ts sought to manufacture a foam having both good dime=i Llity and t2ie--ma-l -4"-sillation using hydrocarbons as blow ts. This referen-ice taught t-he use oú a particular Mixture and =pp-r.tane blowing agents ir. combination with a polyol c alicyclic alk-mes, isopentane articular =lar percents, a made up of an aromatic initiated poiye,-he-- polyol owatic polyester polycl, a---d a dialferent amine-:Lrltiatrzpclyethe= pc-,yol. As cia polyethar M-yol. Smits suggested usi:2.g a--.

alkylenc oxide adduct of a plto=aidehyde resin. the particular mixtu=e c! alicyc116 and isomeric aliphatic alkane 2 blowing agents is taught by Smits as producing a foam having good thermal insulat-lon values.

The problem of obtaining a closed call rigid polyurethane foam having both good dimensional stability and thermal insulation at low densities was also discussed in -An Insight Into The Characteristics of a Nucleation Catalyst 1 EWC-Pree Rigid Foam Systemo by Yoshimwa at al. This publication reported the results of evaluations on a host of catalysts used in a standard polyurethane formulation to test the effects of each catalyst on the thermal insulation and dimensional stability of the foam. The standard formulation used contained 40 parts by weight of a sucrose-based polyether polyol, 30 parts by weight of an aromatic amille-initiated polyethe= polyol, and 30 parts by weight oil. an aliphatic amize-initiated polyether polyol, in a 1.1 weight ratio of aromatic to aliphatic amine-initiated polycls. This lormulation was selected based upon the findings that sucrose and aromatic amine-based polyether pollyols exhibited poor solubilit-ies with cyclopentane, while aliphatic amine-based polyether polyols provided the best solubility for cyclopentane. As a result, 30 parts by weight of the aliphatic amine-initiated polyether polyal was used in the standard formulation.

others have also tried to modify the polycl components in a polyol composition in an attempt to solubilize a hydrocarbon blowing agent in the polyol composition. In U.S. Patent 5,547,998 (White at al), the level of aliphatic amine-initiated polyether polyols in a polyol compositlion is 11-Mited to solubilize cyclopentane in the polycl composition. When reacted with an organic isocyanate, the polyol composition, comprising an axomatic amine-initiated polyoxyalkylene polyether polyol and an ai-Jphat,-c am-ne- iniclbated polyoxyalkylene polyether polycl -4-11 an amount of 10 weight percent or less by weight of the polyol composition produces a d=ensionally stable rigid closed cell poly,=ethane foam having good thermal insulation properties.

in C.S. Patent 5,648,019 (Vaite at al). the level of aromatic polyester polyols in a polycl composition is preferably limited to 18 weIght percent or less to improve the solubility of blowing agent in the polycl composition. The polycl composition is preferably reacted with an organic isocya,.,iate to produce a rigid closed cell foam having good thermal insulation and dimensional stability.

3 Thus, it would be desirable to provide a polyester polyol composition which has a hydrocarbon blowing agent solub-4-lized therein which can be used to produce dimensionally stable rigid polyurethane foam having good ther-mial insulation properties.

According to the present invention, a stable polyester polycl composition is provided comprising a phthalic arhydrideinitiated polyester polyol, a C4-CS hca=.bon blowing agent, and a compatibilIzing agent, wherin the blowing agent is soluble:L-i the polyol composition. The 9Matibilizing agent comprises an oxyethylated fatty acid or fatty alcohol having an nB of from about 7 to about 12, preferably from about 8 to about 11, most preferably about 10. In a preferred embodiment of the present invention, the compatibilizing agent is an oxyethylated fatty acid of the general formula k-WO(E0).xE, wherein R, is a C14 to C26 alkyl chain, EO represent& an ethylenne oxide unit, and x is from about 5 to about, 12 In-me embodiment, the compatibilizing agent comprises a Cle-C2o fatty acid-init-4ated oxyethylate having an average of about 8 ethylene oxide units per molecule.

Preferably, the compatibiliz-;xW agent is present in an amount of from about 1.0 to about 25.0, more preferably 5.0 to about 15.0, most preferably 7.0 to ut 10.0, parts by weight based on 100 parts by weight of t" polyester polyol.

The blowing agents employed used in assoc-atJh'on w:Lth the polycl compositions of the pr 1.

"ant invention have been found to offer lower densities, improved X factors, improved thermal insulation properties and oved dimenslonal stabilities over foams produced using other L01 41 - yol systems. The compatibilizing agent preferably &-^acildtata"-.lub4-l--4zing the blowing agent in the polycl composition with It-sac=ificing, and advantageously improvi.rlg, the thermal L and dimensional stability of the resulting polyurethane The blowing agent is preferably selected from the group of k,,yd--ocarbo.,is, including isopentane, -normal pentane, neope-,itana,,--" -clopentane and m4xtures thereof. A preferred blowing agent m comprises a bland of isopentane and/or normal pentane and alpentane. In another embodiment of the present invention, the bhpring agent comprises a blend of j cyclopentane and isopent=,& "Cerably in a weight ratio of about 70:30 to about 40:60. PO amount of blowing agent present in the polyol composition LG f erably at least about 5. 0 parts WPM by weight based on 100 part#'by weight of the polyester poiyol.

In preferred embodiments of invention, the amount of blowing age== in the polycl composl is from about 7 to about 30. more preferably from about 20 to,-t 30, most preferably from about W- 4 24 to about 27 parts by weight, based on 100 parts by weight of the polyester polyol.

There is also provided a polyisocyanate based rigid closed cell foam made by reacting an organic isocyanate with a polyol composition in the presence of a blowing agent, wherein the polycl composition comprises:

a phthalic anhydride-inltiated polyester Dolyol, preferably having a hydroxyl number of 200 meq. polyol/g KOH or more, preferably in an amount of at least 50.0 percent by weight based on the weight of all polyol components in the polyol_.,t,on; corrpos 1. - b) a blowing agent; and c) an oxyethylated faty acid or fatty alcohol compatibii-zi.,ic; agent.

Again, the blowing agent comprises a Cg-Cs hyd-rocarbon and -4s present in an amount of at least about 5.0 parts by weight, based on 1600 parts by weig-ht of the polyester polyol. By employing these cors-"ituents in the polycl composition, the blowing agent is soluble in the polyol composition. There is also provided a polyurethane foam comprising the reaction product of an organic Jsocyanate and a polyol composition containing the aforenentioned blowing agent.

There is also provided a method of making a poiyisocyar.atp- based rigid closed cell foam comprising reacting an organic isocyanate with a phthalic anhydride initiated polyester polyol composition into which is incorporated a hydrocarbon blowing agent preferably in an amount of at least 5.0 parts by weight, based on 100 parts b..

by weight of the polyester polyol. Preferably the polyester polyol has a hycl--oxv.l number of 200 meq. polycl/g KOF. or more. Z= another aspect of the invention, the polyester polyol is preferably present in the polyol composition in an amount at least 50.0 percent by weight, preferably at least 60.0 percent by weight, most preferably at least 75.0 percent by weight, based on the weight of all polycl components in the polycl composition. An oxyethylated fatty acid or fatty alcohol compatibilizing agent is preferably incorporated into the polyo! composition.

There is provided a storage stable polyol composition coraprising 45 a polyester polycl, a hydrocarbon blowing agent and a compatibilizing agent. A polycl composition is deemed -storage stablem or Osoluble' when the poiyo! composition has the capacity of retaining the blowing agent in solution or in a dissolved state for a period of at least 5 days. The determination of whether or not the blowing age.-t is in solution or dissolved or soluble is measured by mixing the blowing agent with the polyol composition ingredients in a clear glass jar, capping the jar, vigorously agitating the contents in. the jar and lett-bn.g the contents remain still foz 5 days at room temperature without agitation. It upon visual U-ction there is no phase separation such that two discrete lay&= are formed, the blowing agent is deemed soluble in the Polyol composition, and the polyol composition is deemed s to=a--__ stable This test which lasts at least five days is only for purposes c,' measuring whether a particular polyol composition formulation is adequate to solubilize the blowing agent. As discussed further below, the blowing age-pit may he added to the polycl composition weeks prior to foaming, secdbd- prior to foaming, or at the mix head. The scope of tU invention includes each of these embodiments. By stating thaile blowing agent is soluble in the polvol composition, it is meant that the polyol composition employed must be capable of IMIntaining a single phase product by visual inspection. in some dues, this may mean that a particular blowing agent forms a microlsion with the polyol and other components. An important cra';sr-ia is the uni.-o= dispersal of the blowing agent during t^ aming process as described herain.

Where it is said that the pl composition -contains, a blowing agent or that the blowIng a --t; is adissolved in', Isolubilizedll or ain solution, with the 1 composition, this would include those embodiments whe-re the ing agent is miXed with the other polyol composition ingradi, for a period of time sufficient to uniformly dissolve the bl -agent in the polyol composition prior to introducing the composition into the mix head for reaction with an org ---,zocyanate compound, and would not include those embodiments blowing agent is metered as a separate stream into a di DW head for reaction with an organic isacyanate.

The polyol composition of t i phthalic anhydride-in. at blowing agent and a oxya 0 compatibilizing agent hhaavv4:i n 1%^ "",aA4="t-e 1-hzf- resent invention contains a lyester polyol, a Cd-C6 hydrocarbon -d fatty acid or fatty alcohol ELB of from about 7 to about 12.

t r may luded in the polycl composition ly are ocher polyols, cata vs 45 flame retardants, fillers, surfactants, other blowing agents, Ilizers and other additives.

-IU 6 The polyester polycls useful in accordance with the teaching of the present invention include phthalic anhydride-initiated polyester polyols. Preferably, this polyester polyol has a hydroxyl number of at least 200 meq. polyol/q KOH. These polyester Dolyols provide improved dirne-nsional stability to a rigid foam of the present invention. These phthalic ar.hydride-initiated polyester polycls are gene-rally described in U.S. Patent Nos. 4,644,048; 4,644,047; 4,644,027; 4,615,822; 4,608,432; 4,595,711; 4,529,744; and 4, 521,611, the disclosures of which are incorporated herein by reference.

Particularly preferred polyester polycls of the Present invention include STEPANPOLS PS2352, a phthalic anhydride-initiated polyester polyol commercially available from Stepan Chemical Company (Northfield, TIL).

The overall amount of phthalic anhydride-initiated polyester polyol is preferably at least 50.0 weight percent, more preferably 60.0 weight percent. most preferably 75.0 weight percent based on the overall weight of all polycl components in the polyol composition. in one embodiment, the phthalic anhydride- initiated polyester polyol is the sole polyol component in the polyol composition. The polycl composition of the present invention may contain polyols other than t_he phthalic anhyd--ide-:Ln-4t-ated polyester polyol described above, e.g., other polyester polvols and polyethe-- polyols including aromatic am_Jn-einitiated polyols and aliphatic amine-initiated polyols, to= example.

The amount of add-it-Jonai polyols relative to the polyester polycl is not intended to be limited so long as the desired objective of manuf actu, ring a dimensionally stable foam having good thermal insulation values, and optionally, but preferably solubilizing the blowing agent in the polyol composition can be achieved. in this regard, it should be understood that the predominant factors in formulating a stable polyol composition according to the present invention include the limited ability of the phthalic anhye---ide initiated polyester polyol to solubilize blowing agents and the lim-Ited abillity of specific hydrocarbon blowing agents or blends thereof to blend into polyester polyols, particularly the phthalic anhydride-initiated polyester polyol. At the same time, one ski-lied in the art will appreciate that certain hydrocarbon blowing agents will provide distinct physical characteristics to an isocyanare-based foam, which characteristics must be taken into account when developing a polyeste-- polyol composition or rigid foam. Under a preferred erabod,-ment of the present invention the amount of addItional polyols, including aromatic or aliphatic 7 amine-initiated polyoxyalkylene polyether polyols and other polyester polyols, present in the polycl composition is less than about 20.0, more preferably less than about 15.0, most preferably less than about 10.0 percent by weight based oil the weight of all 5 polyol components in the polyol composition.

Suitable additional polyester polyols include those obtained, for example, from polycarboxyUc acids and polyhydr4c alcohols. A suitable polycarboxylic acid-way be used such as oxalic acid, malonic acid, succinic acid, giutaric acid, adipic acid, pimalic acid, suberic acid, azelaic acid, sabacic acid, brassylic acid, thapsic acid, maleic acid, fumaric acid, glutacor--,c acid, a-hydro=c acid, 8- hydromuconic acid, a-butyl - a- ethyl -g lutaric acid-, &.B- dielbhylsuccin.Lc acid, isophthalIc acid, teraphthallt- acid, phtalic acid, hamimailitic acid, and 1,4-cyclohexanedica lic acid. A suitable polyhydric alcohol may be used suc as thylenre glycol, propylene glycol. dipropylene glycol, trimethr^a glycol, 1,2 butanediol,!,5-pentanediol, 1,6-h.exanadiol, 1,7-haptanediol, nydroqu.-, none, resorcinol glycerol, glycerin, 1,1,1-tz-Jmethylol-propane, pzythr-4tol, 1, 2, 6-hexane trio!, a-methyl glucoside, sucroactT."d sorbItol. Also included with-in the term Opolyhydric alcoho%M-[Are compounds derived from phenol such 2,2-bis(4-hyclroxyphanoll-proparle. commonly mown as Bisphenol A. Preferred addit- polyester polyols are aromatic polyester polycls.

The hydroxyl-contain:Lng poly"ter may also be a polyester amide such as is obtained by inclmlng some amine or amino alcohol in the reactants for the pration of the polyesters. Thus, polyester amides may be obtd by conde-nsing an amino alcohol such as ethanolamine with tb-polycarbo>-.ylic acids set forth above or they may be made the same components that make up the hydroxyl-containing star with only a portion of the components being a diamins as ethylene diamine.

Another suitable polyester IM1 useful as an additional polyester polyol is an a7 thylglucoside initiated polyester polyol derived from polyet& terephthalate. This polyol has a molecular weight of approxy 358, a hydroxyl number of about 360 meq polyol/g KOR and a. nxl average functionality of 2.3. IMMIN As alluded to above, eact _7 polyols, including the polyester polVol, preferably have hY- 1 numbers of 200 or more mecl polyol/q KOH. At hydroxyl s of less than 200. the dimensional stability of may begin to deteriorate.

The optimum nominal functio ty of aromatic polyester polyol W- 1 8 appears to be 2 or more, with ar- average hydroxyl numbers of 350 or more. Likewise, the optimum nominal functionality of each amine-i,n. itiated polyol appears to be 4 or more, with hydroxyl numbers of 400 or more.

Other polyols besides the polyester polycls described herein can be added to the PO1YO1 composition provided the desired objectives discussed above can be achieved. Such poiyols would include polyoxyalkylene polyether polycls, polythioether polyols, polyester amides and polyacetals containing hydroxyl groups. aliphatic polycarbonates containing hydroxyl groups, amine terminated polyoxyalkylene polyethers, polyester polyols, other polyoxyalkylene polyether pclyols, and graft dispersion polycit-. In addition, mixtures of at least two of the aioresa-d polyols can be used. The preferable additional polyols are polyoxya-ikylene polyether polyols; however, the total amount of additional polycls employed will preterably not exceed 20. 0 weight percent based on the total weight of all polyol components in the polyol composition.

Included among polyoxyalkylene polyether polyols are polyoxyethylene polyols, PO1YOxyPropylene polyols, polyoxybutylene polyols, polytet=amethylene polycls, and block copolymers, for example combinations of PO lyoxy-P ropy! anre and polyoxyethylene poly-1,2-oxybutyle-ne and polyoxyethy-le-"e polyols, poly- 1,4-tetzamethylene and polyoxyethylene polyols, and copolymer polyols prepared fr= blends or secraential addition of two or more alkylene oxides. The polvoxyalkylene polyether polycls ray be prepared by any known process such as, for example, the process disclosed by Wurtz in 1859 and Encyclopedia of Chemical Technology, Vol. 7, pp. 257-262, published by Inte=science Publishers, Inc. (1951) or in U.S. Pat. No. 1,922,459. The alkylene oxides may be added to the -initiator, i.-id-v- dually, sec-ruentially one after the other to form blocks, or _ir_ mixture to form a heteric, polyether. The polyoxyalkylene polyether polyols may have either primary or secondary hydroxyl gwoups.

The polyoxyalkylene polYether PO1YO1 may have aromatic amine-initiated or aliphatic amine-initiated polyoxyalk-ylene polyether polyols. it is preferred that at least one of the amine-initiated polyols are polyether polyols terminated with a secondary hydroxyl group th=ough addition of, for example, p=opylene oxide as the terminal block. It is preferred that the amine-initiated polyols contain 50 weight percent or more, and up to i00 weight percent, of secondary hydroxyl group forming alkylene oxides, such as polyoxypropylene groups. based on the 9 weight of all Oxyalkylene groups. This amount can be measured by adding 50 weight percent or more of the secondary hydroxyl group forming alkylene oxides to the initiator molecule in the course ot manufacturaing the polyol.

Suitable initiator molecules l-or the polyoxyalkylene polyether compounds are primary or saco amines. These would include, for the aromatic amineiniti polyether polycl, the aromatic amines such as aniline, Nalkylphenylene-diamines, 2,40-, 2,21-, and 4, 41 -me thyl enediani line, 2,6- or 2,4-toluenediamine, vicinal toluenediamines, o-chloro-ani line, p-aminoaniiine, 1,5- diaminonaphthale.ne, methylene dianiline, the various condensation products of an:Llina and formaldehyde, and the isomeric diaminotoluenes, with preference given to vicinal toluenediamines.

For the aliphatic amine-inútiated polyol, any aliphatic amine, wIllether branched or unbranethed, substituted or unsubstituted, saturated or unsaturated, may be used. These would:L-icli-,de, as examples, mono-, di, and.txialkanolami.-.es, such as monoethanolamine, methylamin y.trilsopropanolamine; and polyamines such as ethylene &immine, propylene diamine, d i ethyl enetriamine; or 1,3-diazi=propane, 1,3-diam- ;nobutane, and 1,4-diaminobutane. Prefele aliphatic amines include any of the diamines and triamin",.most preferably, the d.;amines.

Pre-Earably, the additional Polyols have number average molecular weights of 200-750 and nominal functionalities of 3 or more. By a nominal functionality, t is meant that the functionality expected is based upon the ktgcti=ality of the initiator molecule, rather than the ac functionality of the finalpolyethex afte-, manufacture.

The polyoxyalk-ylene polyether polyols are polyoxyalkylene polyether polyols. These polyols may generally be prepared by polymerizing alkylene oxideciigth polyhydric amines. Any suitable alkylene oxide may be used " as ethylene oxide, propyleane oxide, butylene oxide, amylq"-,oxide, and mixtures of these oxides. The polyoxyalkylene ather polyols may be prepared from other starting materials-wach as tetrahydrofuran and alkylene oxi de- t e trahyd--ofugp. mixtures; epihalohyd=irs such as epichlorohydrin; as well an V -- lane oxides such as sty-rene oxide.

Other polyoxyalkylene polya polyols may include those initiated with polyhydronl CO=ds. EXamP1G5 Of such initiators are trimethylolpze, glycerine, sucrose, sorbitol, Propylene glycol, diPrOPYIene glycol, pentaerythritol, and 2,2-bis (4- hydroxyphe--.y-l) -propane and blends theraof. The preferred polyols are initiated with polyhyd--oxyl compounds having at least 4 sites reactive with alkylene oxides, and further may be oxyalkylated solely with propylene oxide. in a more preferred embodiment, the additional polyol is a polyoxyalkylene polyether polyol having a nominal functionality of 5 or more, that may be initiated with a polyhydroxyl compound. The high functionality serves to increase the crosslink density to provide a dimenstLonally stable foam.

Suitable polyhydric polythicethers which may be condensed with alkylene oxides include the condensation product of thiodiglyco-1 or the reaction product of a dicarboxylic acid such as is disclosed above for the preparation of the hyd--oxyl-cor-taining polyesters with any other suitab le ttioether polyol.

Polytiydroxyl-containing phosphorus compounds which may be used include those compounds disclosed in U.S. Pat. No. 3,639,542.

Preferred polyb-ydroxyl-containing phosphorus compounds are prepared from alkylene oxides and acids of phosphorus havi;.=g a P205 equIvalency of from about 72 percent to about 95 percent.

Suitable polyacetals which may be condensed with alkylene oxides include the reaction produce of formaldehyde or other suitable aldehyde with a dihydric alcohol or an alkylene oxide such as those disclosed above.

Suitable aliphatic th.,;bols which may be condensed with alkyIene oxides include alkanethiols containing at least two -SH groups such as 1,2-athaned-thlol, 1,2-propaned-i,--hiol, 1,2-propanedithial, and 1,6-hexanedith..iol; alkene thiols such as 2-butane1.4-dithici; and alkene thiols such as 3-hexe-ne-1, 6-dit-'ltiol.

Also suitable are polymer modified polyolS, in particular, the so-called graft polycls. Graft polyols are well)mown to the art and are prepared by the in situ polymerization of one or more vinyl monomers, preferably acrylonitrile and styrene, in the presence of a polyether polyol, particularly polyols containing a minor amount of natural or induced unsaturation. methods of preparing such graft polyols may be found in columns 1-5 and in the Examples of U.S. Patent No. 3,652,639; in columns 1-6 and the Examples of U.S. Patent No. 3.823,201; particularly = columns 2-8 and the Examples of U.S. Patent No. 4,690,956; and in U.S.

11 Patent No. 4,524,157; all of which patents are herein incorporated by reference.

Non-graft polymer modified polyols are also suitable, for example, as those prepared by the reaction of a polyisocyanate with an alkanolamine in the prase-nce of a polyether polyol as taught by U.S. Patent 4,293,470; 4,296.213; and 4,374,209; dispersions of polyisocyan= containing pendant urea groups as taught by U.S. Pattnt 4,386,167; and polyisocyanurate 10 dispersions also containing-blurat linkages as taught by U.S. Patent 4, 359,541. Other-polymer modified polyols may be prepared by the in situ sizdt-Mduction of polymers until the i particle sIze is less than preferably less than lomm.

-7 The average hydroxyl number61 the polycls in the polyol composition should praterab3& be 200 maq polycl/g KOH = mc-re and, more preferably 350 moq Volyol/q KOR or more. indivj4dual poly-ols may be used which ú01below the lower limit, but the average should be within thic=ge. Polyol COMPOSI: tions whose polyols are on average withW-tlis range make good dimensionally stable foams.

In addition to the foregoing the polyester polyol composition of. the present invention also:bolildes a blowing agent selected from the group consisting of C4-Qi]Wdrocarbons and mixtures thereof. The blowding agent may be a -,and solubilized in the polyol composition for storage:z&m to= use -,-. a f caming apparatus or may be added to a pr,'I W in the foaming apparatus and preferably solubilized in tw.- pos.-tion immediately polyol con prior to pumping or mater a foaming ingredients to the mix head. Alternatively. owing agent may be added to the foaming ingredients in although full solubility of time the blowing agent,' in the mix head. The a invention is that the poli of storing stable polyol blowing agent, or solubil polyol composition in the mix head, to manufacturaRz polyol composition of the enable a variety of blow rigid closed cell polyiso objectives.

-7f ST, mix head as a separate stream, b limited due to the short amount sed to the polycl composition of the polycl composition of the _osition provides the flexibility itions containing the desired the blowing agent with the end tank. or adding it at the of the desired quality. The tion is specially adapted to ts to be employed to produce to based foams meeting the desired 12 The amount of blowing agent used is preferably 5.0 parts by weight or more based on 100 parts by weight of the polyester polyol in the polycl composition. The particular amount of blowing agent will depend in large part upon the desired density of the foam product. For most applications, polyurethane tree rise densities to= thermal insulation applications range from free rise densities of 0.5 to 10 pcf, preferably from 1.2 to 2. 5 pcf. The preferred overall densities of foams packed to 10% by weight, meaning the percentage by weight of foam ingredients above the theoretical amount needed to fill the volume of the mold upon foaming, are from about 1.2 to about 2.5 pcf, more preferably from 1.3 to 2.0 pclj. The amount by weIght of all blowing agents is generally, based on the weight of the polycl composition. from about 5.0parts by weight to 40.0 parts by weight. and more preferably, 7.0 parts by weight to 30.0 parts by weight, most preferably from about 20.0 to about 30.0 parts by weight, based on 100 parts by weight of the polyester polyol. In one embodiment herein, the blowing agent is present in an amount of from about 24.0 to about 27. 0 parts by weight, based on 100 parts by weight of the polyester polycl.

The blowing agents useful in the polyol composition of the present invention are selected from the group consisting C4-C hydrocarbons and mixtures theireof. The hydrocarbons are prefe-rably the sole blowing agent, optionally with water. Thus, such blowing agents include butanes, pentanes, hexanes, and mixtures thereof. Such blowing agents may be 1:Lnea=, unbranched or cyclic in chemical structure. Preferred blowing agents are the pentanes, iscpentane, normal pentane, cycloperitane and neopentane. The pentanes may be incorporated into the polyol composition of the present invention alone or as a bland of two or more thereof. In one embod4ment of the present invention. the blowing agent comprises a mixture of cyclopentane and isopentane, which preferably has a weight ratio of between about 70:30 and 40:60. Furthermore, mixtures of normal pentane with isope-ntane and/or cyclopentane are also preferred. Blowing agents comprising 4sopentane and cyclopentane provide excellent dimensional stability and insulation properties to a r4,.gid foam of the present invention. Generally, the selection of the blowing agent utilized will depend an the desired physical cha=acterist-,cs of the polyurethane foam. Those skilled in "-he art are familiar with the effects provided by the blowing agents of the present invention.

The hydrocarbon blowing agents of the present invention are generally available from manufacturers of fractional distillation products from petroleum, including Phillips Petroleum and E=on 13 Corporation. One known method of producing a high purity cyclopentane blowing agent is disclosed in U.S. Patent 5,578,552 (Blanpied et al).

is The above hydrocarbons may be used as the sole blowing agent in the present invention. However, additional limited amo=ts of auxiliary blowing agents may he used, including EM s and ECPCI s. Suitable hydro:Eluorocar, parfluorinated hydrocarbons, and fluorinated ethers (collectively referred to herein as EPC's) 10 which are useful as additi blowing agents include difluoromethane WC-32); 1,1,1,2-tatraflucroethane (HPC-134a); 1,1,2,2-tatra:!luoroathane (]CC-134); 1,1-difluoroethanp(HFC- 152a); 1,2difluoroath WC-142), trifluoromethane; heptaflucropropane; 1,1, 1-tftfluorcethane; 1,1,2-trifluoroethane; 1,1,1,2,2-pentaflucropropant; 1, 1,1,3,3-pentaflucropropane (EFEC 245fa); 1,1,1,3-tetralluon)pane; 1,1,2,3, 3-pertafluorop=opane; 1,1,1,3,3-pentafluoro-n.butme; 1,1,1,2,3,3,3heptafli.,.oropropa.,ie (F-PC 227ea); hex at 1 uorocycl"ropane (c-216); 6cta.-Fl-uorocyclobutans (C-31t); perfluorotetrahyd.-o4&,i--an; 20 perfluoroalkyl tetrahydrofu; perfluorofuran; perfluoro-propans, -butane. cyclobutane, -pentane, -cyclopentane, and -hex=, -cyclohexane, -heptane, and -octane; perl"luorod-4ethyl ether; pertluorodipropyl ether; and pert luoroethyl propyl ether.. -Preferred among the EFC blowing 25 agents are F2C 134a and FM 2 36ea, respectively.

Suitable hydrochlorofluoro blowL-ig agents which may also be used as additional blowiR- A agents are 1-ch.loro-1,2-d4--fluo.-oethant-l-chloro-2,2-difluoroehane (142a); 1-chloro-l,l-d.,'fluoroec (142b); 1,1-dictLIoro-i-fluoroethane (141b); 1chloro-1,1,2-trd4.ti roathane; 1-chloro-1,2,2-trifluoroet- I; 1,1-diochlorc-1,2-di.Oluoroathane; 1-chlorc-1,1,2,2-tatrafluoi, a (124a); 1-chloro-1,2,2,2-tat=afluoze (124); 1,1-d;chloro-1,2,2-trifluo i,l-dichloro-2,2,2-trifl= e (123); and 1, 2-dichlo=o-1, 1, 2-trifluoi&alume (123a) monochlorodifluoromethan& (!C-22); 1-chlozo-2,2,2-t-"ifluoroothabi (ECEC-133a); ge-m-r-hloro!luoroethylene (MUila); chlorchep tat luoropropane (ECFC-217); chlorodifl=rene (FEWC-1122); and t=ans-chlorofiuoroethylene-&C-1131). Preferred among hydrochlorofluorDcarbon bl^ agents is 1, 1-cUchloro-i- fluoroet:h IW-PC-142.b) 45 W1 14 other blowing agents which can be used in addition to the blowing agents listed above may be divided into the Chemically active blowing agents which chemically react with the iSocyanate or With other formulation ingredients to release a gas for foaming, and 5 the physically active blowing agents which are gaseous at the exothermic foaming temperatures or less without the necessity for chemically reacting with the foam ingredients to provide a blowing gas. Included within the meaning of physically active blowing agents are those gases whic19- are thermally unstable and decomp ose at elevated temperatures.

Examples of chemically active blowing agents are preferentially those which react wlth the isocyanate to liberate gas, such as C02. Suitable chemically active blowing agents include, but are not limited to, water, mono- and polycarboxylic acids having a molecular weight of from 46 to 300, salts of these acids, and tertiary alcohols.

Water is preferentially used as a blowing agent. Water reacts with the organic isocyanate to liberate C02 gas which is the actual blowing agent. However, since water consumes isocyanate groups, an equJvalent molar excess of isocyanate must be used to make up for the consumed isocyanates. water is typically found in minor quantities in the po.',.yols as a byproduct and may be sufficient to provide the desired blowing from a chemically active substance. Preferably, however, water is additionally introduced into the polyol composition in amounts of from about 0.02 to 5 weight percent, preferably from 0.05 to 4 parts by weight, based or, 100 parts by weight of the polyester Dolvol.

The organic carboxylic acids used are advantageously a1-4phatic mono- and polycarboxylic acids, e.g. dicarboxy'-,;.c acids. However. other organic mono- and polycarboxylic acids are also suitable. The organic carboxylic acids may, if desired, also contaLn subs ti which are i'lliert under the reaction conditions of the poly-4socyanate polyaddition or are reactive with isocyanate, and/or may contain olefinically unsaturated groups. Specific examples of chemically inert substituents are halogen atoms, such as 16-luorine and/or chlorine, and alkyl, e.g. methyl or ethyl. The substituted organic carboxylic acids expediently contain at least one further group which is reactive toward isocyanates, e.g. a mercapto group, a primary and/or secondary amino group, or preferably a primary and/or secondary hydroxyl group.

Suitable carboxylic acids are thus substituted or unsubstituted monocarboxylic acids, e.g. formic acid, acetic acid, propionic: acid, 2chioropropionic acid, 3-chloropropionic acid, 2,2-dichloropropionic acid, hexanoic acid, 2-ethyl-hexano-ic acid, cyclohexanecarboxylic acid. dodecanoic acid, palmitic acid. stearic acid, cleic acid, 3-macapto-propionic acid, glycolic acid, 3- hydroxnropionic acid, lactic acid. ricinoleic acid, 2-aminopropioziic acid, benzoic acid, 4-methylbenzoic acid, salicylic acid and anthranilic acid, and unsubstituted or substituted polycarboxylic acids, preferably dicarboxylic acids, e.g. oxalic acid. mal=lc acid. succinic acid, fumaric acid, maleic acid, glutaric-acid, adipic, acid, sebac.,&,c acid, dodecanadoic acid, tartaric acid, phthalic acid, isophthalic acid and citric acid. Preferable acids are formic acid, propionic acid, acetic acid, and 2-ettcibexanoic acid, particularly formic acid.

The amine salts are usuallY to=md using tertiary amines, e.g. triethylamine, dimethylbcnzylam-ine, diethylbenzylamine, triethylenediamine, or hydrazint. Tertiary amine salts of formic acid may be employed as chandcally active blowing agents which will react with the organic hocyanate. The salts may be added as such or formed in situ by reaction between any tertiary am-ine (catalyst or polycl) and fort-le acid contained in the polyol composition.

Combinations of any of the athrementioned chemically actIve, A blowing agents may be emplt)j_-, such as formic acid, salts of formic acid, and/or water.

Decomposition type physically active blowing agents that release a gas through th decomposition include pecan flour, amine/carbon dioxide compl and alkyl alkanoate compounds especially methyl and athyl1%=tes.

Generally, the blowing agents of the present invention pose particular problems in incorporation into polyester polyol compositions. particularly pbtUlic-anhydride- Initiated polyester polyols of the present inveAtion. It is preferred to have the hydrocarbon blowing agent slubilized or dissolved in the polyol composition to avoid problms of separation of the hydrocarbon and polyol component and accunalation of the hydrocarbon blowing agent in the head space. Thare is particular concern with the hydrocarbon blowing agents arning all explosion hazard.

Thus, the PO1YO1 Composition of the present invention further comprises an thylated fatty acid or fatty alcohol compatibilizing agent which has an ELB of from about 7 to 12 preferably from about 8 to about 11, most preferably from about 8 to about 10.5. This compatibilizinq agent facilitates the incorporation of the hydrocarbon blowing agents into the polyol composition by solubilizing this blowing agent into the polyol composition. The compatibilizing agent appears to reduce the percentage of gas loss during the foaming process when the hydrocarbon blowing agents of the present invention a--e utilized. Suitable compatibilizing agents linclude the oxyethylated fatty alcohols having an nB of from about 7 to 12, preferably from about 8 to about 12, most preferably from about 8 to about ii.5. Such oxyetl..ylated fatty alcohols preferably have an alkyl chain portion havIng from about 10 to about 20 carbons. One such oxyethylated fatty alcohol is 1CONOL0 DA-4 commercially available from BASF Corporation (kt. Olive, New Jersey), which has an average C10 alkyl chain portion, on average four ú0 units per molecule and has an = of 10.5. Another such oxyathylated fatty alcohol is 1CONOL0 TDA-3 commercially available from RASF Corporation, which has an average C13 alcohol chain portion, an. average three E0 units pe-- molecule, and has an nB oz. about 8.

other suitable compatibilizing age-nts include oxyethlyated fatty acids of the general formula R,-COO(E0)xH, including mixtures thereof, wherein R. is a branched or unbranched alkyl chain, n being the number of carbon atoms in the alkyl chain which is from about 14 to about 26, EO represents an ethylene oxide unit, and x is from about 5 to about 12. In a prefferred embodiment, or.

average R, is from about a C16 to about C20 alkyl chain, and x is from about 6 to about 10. Most preferably the compatibilizing agent comprises a CleC20 fatty acid-initiated oxyethylate having an average of about 8 ethylene oxide units per molecule. such compatibilizing agents are commercially available from BASF Corporation (Y.t. Olive, NJ) as INDUSTROL0 TFA-8 or MAPEdS 400 MOT. BAS? Corporation's MA-PEGO 300 MOT is also a suitable compatibilizing agent.

other suitable compatibilizing agents include the fatty alcohol athoxylates having a limited portion of propylene oxide incorporated Into the chemical structure as a heteric portlon with the ethylene oxide in the compatibilizing agent structure, such as a C,2-15(=-09.7P03.1) which is commercially available as PLURAPACC B25-5 from BA5F Corporation. The amount of propylene oxide should be limited to the extent that the above-described i-=B values are met, the desired objective of manufacturing and dimensionally stable foam having good thermal insulation values, is 17 and optionally, solubilizing the blowing agent in the Dolvol composition can be achieved.

Although not intending to be bound by theory, it is believed that the predominant factors in influencing the effectiveness of the compatibilizing agent to facilitate the incorporation of the blowing agent into the polyester polycl composition include the chain length of the alkyl p"tion of the compatibilizing agent and the re..E of this component. Generally, longer fatty alkyl chain portions in the c=p&%":Llizing agent provided better capacity to solubilize thaocarbon blowing agent. into the polyester polyol. The contant of ethylene oxide in the chemical structure of the compatibIlizing agent Is generally proportion1 to its ability to solubilize the hydrocarbon blowing agent.

The amount of a Compatibilit$ng agent requi-red In the polycl composition of the present Antion will depend largely on the components in the polyol c- sition particularly the polyester polyol component and the bhowing agent utilized. The amount of the compat-ibilizing agent Z=. be easily determined by one skilled in the art. Generally, though, a composition containing cyclopentane as-th blowing agent will require less compatibilizing agent than., ositions containing isopentane or normal pentane. Preferably,;-- the compatibilizing agent is present in compositions conta:Lninq-cpentane as the blowing agent in an amount of from about 1 WAbout 25, more preferably from about 5 to about 15, most prefer from about 7 to about 10 parts by weight, based on 100 parts--", weight cl. the polyester polyol in the polyol composition. In- ositions containing -1sopentane or normal pentane as the blo agent, the compatibilizing agent is preferably present in of from about 10 to 25, more preferably from 12 to abou"--2, most preferably from about 15 to about 20 parts by webased on 100 parts by weigh.. of the polyester polyol in th4bpolyol composition. in compositions containing 50/50 blends of-IC"lo_ze.ntane and isopentane or normal pentane as the blowing aq%L>. the compatibilizing agent will pref erably be present In AMY Amount of f rom about 5 to 2 0. more preferably from 5 to abouoM, most preferably from about 8 to about 12 parts by weight. on 100 parts by weight of the polyester polyol in the po- composition.

o& f.

it 1 At all effective levels atibilizing agent, preferably containing from about 1 t 25 parts by weight of compatibilizing agent b 1 0 pc-L=ts by weig.'it of the polyester polyol in the 1 composition, compositions of the present invention expericW-,&n improvement in the percentage of 18 gas loss during the foaming process as compared to compositions containing no COmpatibilizing agent.

Catalysts may be employed which greatly accelerate the reaction Of the Compounds Containing hydroxyl groups and with tl%.e modified or unmodified polyisocyanates. Examples of suitable compounds are cure catalysts Which also function to shorten tack time, promote green strength, and prevent foam shrinkage. Suitable cure catalysts are organometallic catalysts, preferably organotin catalysts, although it is possible to employ metals such " lead. titanium. copper, mer=.ry. cobalt, nickel. iron, vanadium, antimony, and manganese. Suitable organometallic catalysts, exemplified here by tin as the metal, are represented by the formula: RnSn[X-Rl-Y32, wherein R is a Cl-Ce alkyl or ary.1 group, R1 is a CO-Cle methylene group optionally substituted or branched with a Cl-C4 alkyl group, Y is hydrogen or a hydroiryl group, preferably hydrogen. X is methylene, an -5-, an -SR2C00-, -50OC-, an -03S-, or an - OOC- group Wherein R2 is a Cl-C4 al.kyl, n is 0 or 2, provided that R' is CO only when X is a methylene group.

Specific examples are tin (1.1) acetate, tin (11) octamoate, tin =) ethylhexa,.loate and tin (11) laurate; and dialkyl (!-BC) tin (M salts of organic carboxylic acids having 1-32 carbon atoms, prefe=ably 1-20 carbon atoms, e.g., d-4ethyltir. diacetate, d-ibutyltir. diacetate, dibutyltin diacetate, dibutyltin, dilaurate.

dibi-,tyltin maleate, dihexyltin diacetate, and dioctylt,.ri diacetate. other suitable organotin catalysts are organotIn alkoxides and mono or polyalkyl (I-SC) tin (M salts of inorganic compounds such as butyltin trichloride, dimethyl- and diethyl- and dibutyl- and dioctyl- and diphenyli.- t-In oxide, dibuty"-,t,--i dibutoxide, d.,.(2-ethylhexyl) tin oxide, dibutylt-Jr, dichloride, and d-,'octyltin dioxide. Preferred, however, are tin catalysts with tin-sulfur bonds which are resistant to hydrolysis, such as dialkyl (1-20C) tin dimercaptides, including dimathyl-, dibutyl--, and dioctyl- tin dimarcaptides. A suitable catalyst in compositions of the present invention, is K Hex Cem 977 which is a potassium octoate catalyst in a g'-.vccl (DPG) carrier commercially available from m & T Chemicals.

Te-rtiary amines also promote urethane linkage formation, and include t=4,ethylan-dne, 3-methoxypropy.-dimetbLylamine, triethylenediamine, tributylamine, dimethylberizylamine, N-methyl-, N- ethyl- and N-cyclohexylmo=phol-4ne, N,N.NI,Nl-tet-"amethylethylenediamine. N,N,N',N'-tatrametl..ylbutanediamine or -hexanediamine, 4S N,N,N-trimethyl isopropyl propylenediamine, pentamethyldiethylenetriamine, tetramethyldiaminoethyl bis(di.methy',- aminopropyl)urea, dimethylpiperazine, 19 1-me thy! -4 - dimet:,hylaminoethylpiperaz ine, 1,2-dimethylimidazole, 1-azabicylo[3.3.Oloctane and preferably 1,4-diazabicylo[2.2.2]octane, and alkanolamine compounds, such as trie thano lamina, triisopropa-.iolAmine, N-methyl- and 5 1;-ethyldiethanolamine and dizathylethanolamine.

To prepare the polyisocyanurato (PIR) and PUR-PIR f oams by the process according to the invention, a polyisocyanurate catalyst is employed. Suitable polyis urate catalysts are alkali salts, for example, sodium salts, preferably potassium salts and ammonium salts, of organIC carboxylic, acids, expediently having from 1 to 8 carbon at.P. preferably 1 or 2 carbon atoms, for example, the salts of fc acid, acetic acid, propionic acid, or octanoic acid, and iwis(dialkylaminoethyi)-, t--4-s(d-4methylaminopropyl)-, r:Ls(dimethylam.,nobutyl)- and the corresponding tris(diethyla alkyl)-s-hexahydrotriazines.

However. (trimathyl-2-hydr ")ammonium formate, (trirnethyl-2-hydroxypropyl)aw=um octancate, potassium acetate, potasslum octoate potassium Jte and tris (dime thylaminopropyl) s- ydrotrazine are IM Wrethane-containing foaMS matj p prepared with or without the use of chain extenders andluwj=osslink-J. ?lg agents, which are not necessary in this invention ta achieve the desired mechanical zw_hardness and dimensiona! statUity. The chain extenders and/or crossl-linking agents used h"-& number average molecular weight of less than 400, preferabl, extende--s have polyoxyalkyl average molecular weight of dialkylene glycols and ali araliphatic diols having ú polyisocyanurate catalysts wiUch are generally used. The suitable polyisocyanurate catalyst:L,-f"ally used in an amount of from 1 to 10 parts by weight, prafly &from i.5 to 8 parts by weight. based on 100 parts by weight k the total amount of polyols.

ARM= 6 0 to 3 00; or if the chain ,!cups, then having a number than 200. Examples are c, cycloaliphatic and/or to 14 carbon atoms, preferably from 4 to 10 carbon atoms, 4,mh, ethylene glycol, 1,3-propanediol, 1,10-decl, c-, m-, and p-dil.ydroxycyclohe.xane. diegene glycol, dipropylene glycol, and preferably 1,4-butanadl&IJL--: 1. 6-bAxanediol, 4 0 b i s (2 -hydroxye thyl) hydroqu, triol s such as 1, 2, 4 - and 1,3,5-trib.ydrox-ycyclohex= ycerol, and trimethylolpropane.

Polyurethane foams can alsoM-p=epared by using secondary aromatic diamines, prizary "Mat:Lc diamines, and/or 3,31-, 5,51-tetraalkyl-subs-tle--"-ted diaminoelphenylmetl,-anes as chain extenders or r-=osslinkincj agents instead of or mixed with the above-mentioned cUois andlor triols.

The amount of chain extender, crosslinking agent or mixture thereof used, if any, is expediently from 2 to 20 percent by weight, prefEerably from 1 to 15 percent by weight, based on the weight of the polyol composition. However, as previously alluded to. it is preferred that no chain extender/wosslinker is used for the preparation of rigid foams since the polyether polyols described above are sufficient to provide the desired mechanical properties.

it desired, assistants and/or additives can be incorporated int-0 the reaction mixture for the production of the cellular plastics by the poiyisocyanate polyaddition process. Specific examples include surfactants, foam stabilizers, cell regulators, fillers, dyes, pigments, flame-proofing agents, hydrolysis-protection agents, and fungistatic and bacteriostatic substances.

Examples of suitable surfactants a=e compounds which serve to regulate the cell structure of the plastics by helping to control the cell size in the foam and reduce the surface tension during foaming via reaction of the polycl composition with an organic isocyanate as described herein.

Specific examples are salts of sulfonic acids. e.g., alkali metal salts or ammonium salts of dodecylbenzene- or d-Jnaphthyimethanedis.alion.ic acid -and ricinoleic aci cl; foam stabilizers, such as siloxane- oxyalkylene copolymers and other organ polysiloxanes, oxysthylated alkyl-phenols, oxyethylated fatty alcohols, paraffin oils, castor oil esters, ricinoleic acid esters, Turkey red oil- and groundnut oil, and cell regulators, such as paraffins, fatty alcohols, and d-JMethylpolys-4l-oxanes.

- Preferred sizrfactants include the silicone-containing surfactant polymers. The surfactants are usually used in amounts of 0.0I to 5 parts by weight, based on 100 parts by weight of the polyol component. A suitable surfactant in compositions of the present invention comprises Tegostab@ B-8462 silicone surfactant commercially availiable from Goldschmildt company.

por the purposes of the invention, fillers are conventional organic and inorganic fillers and reinforcing agents. Specific examples are inorganic fillers, such as silicate minerals, for example, phyllosilir-ates such as antigorite, serpentine, hornblends, amphiboles, chrysotile, and talc; metal oxides, such as kaolin. aluminum oxides, titanium oxides and iron oxides; metal salts, such as chalk, barite and inorganic Pigments, such 21 as cadmium sulfide, zinc sullide and glass, inter alia; kaolin (china clay), aluminum silicate and co-precipitates of barium sulfate and aluminum silicate, and natural and synthetic fibrous minerals, such as wollastonite, metal, and glass fibers of various lengths. Examples of suitable organic fillers are carbon black, melamine, colophony, cyclopentadienyl resins, cellulose tibers, polyamide fibers, pobmcrylonitrile fibers, polyurethane fibers, and polyester fibersb"ed on aromatic andlor aliphatic dica--boxyl-Jc acid esters, MAn particular, carbon fibers.

The inorganic and organic fiUra may be used individually or as mixtures and may be introdu6bd7into the polyol composition or isocyanate side in am unts rom 0.5 to 40 percent by weightj based on the weight of c _Mats (the polycl composition and the isocyanate); but the contentU mats, nonwovens and wovens made from natural and synthetic s may reach values of up to 80 percent by weight.

P-x-amples of suitable flameptMtlng agents are tricresyl phosphate, t---is(2-chloroathyl"hosphate, tris(2-chloropropyl) phosphate, and tr-4s(2,3-dibrropyl) phosphate. A suitable flame retardant in compositi of the present invention comprises IFY.ROL@ PC?, which WA tris (chloro propy!) phosphate commercially available from Isur' ght & W4 lson.

in addition to the above-mc-n halogen-substituted phosphates, it is also possiC to use inorganic or organic P5Ld phosphorus, alumLium oxide flameproofing agents, such hydrate, antimony trioxide, Uic oxide, ammonium polyphosphate 30 (T-xol-it@) and calcium sulta W'wcpandable graphite or cyanuric acid derivatives, e.g. mel, or mix=es of two or more flamep.-m.oofing agents, e g.', -ium polyphosphates and melamine, and,if desired, corn star ammonium poiyphosphate, A melamine, and expandable gr andlor, it desired, aromatic polyesters, in order to fl f the polyisocyanate polyaddition products. In 9 from 2 to 50 parts by weight, preferably from 5 to 25 par welight, of said flameproofing 1 agents may be used per 100 by weight of the polycl co=osition.

Further details on th tional assistants and additives mentioned a:ovo obtained from the specialist literature, for example, f rs and monograph by J.E. Saunde K.C. Frisch. High Polymers, c XVI, ?olyurethanes, Parts 1 and 2, Interscience Publish '41962 and 1964, resPectively, or Kur.ststoff-F-an,dbuch, Polyur volume VII, WEE 22 Carl-Hanser-Verlag, Munich, vienna, Ist and 2nd Editions, 1966 and 1983; incorporated herein by reference.

is Suitable organic polyisocyanates, defined as having 2 or 5 more isocyanate functionalities, are conventional aliphatic, cycloaliphatic, araliphatic and preferably aromatic 4socyanates. Specific examples include: alkylene diisocyanates with 4 to 12 carbons in the alkyle-ne radical such as 1,12-dodecane diisocyanate, 2-ethyl-1,4-tetramethylene diisocyanate, 2-metbyl-I,S-pe-itamethylene diisocyanate, 1,4-tetrame-khylene diisocy_anate and preferably 1,6-hexamethylene diisocyanate; cycloaliphatic diisocyanates such as 1,3- and 1,4-cv-clohaxane diisocyanate as well as any mixtures of these isomers, i-isocyanato-3,3,5- trimethyl-S-isocyanatomethylcyclohexar-e (isophorone diisocyanate), 23- and 2,6-hexahydrotoluene diisocyanate as well as the corresponding 4. someric mixtures, 4,4,- 2,21-, and 2,41-dicyclohexylmethane diisocyanate as well as the corresponding isomeric mixtures and preferably aromatic diisocyanates and polyisocyanates such as 2,4- and 2,6-toluene diisocyanate and the corresponding isomeric mixtures 4,43-, 2,4'-, and 2, 2'-diphenylmethane dilsocyanate and the corresponding isomeric mixtures, mixtures of 4,41-, 2,4'-, and 2,2-diphe-,iylmethar,e d-i-Jsocyanates a-nd polyphenylenepolymethylene polyisocyanates (crude 1-MI), as well as mixtures of crude MD1 and toluene dlisocyanates. The organic di- and polyJ.socya-"-ates can be used indiv-5. dually or in the form of mixtures. Particularly preferred for the production of rigid foams is crude YDIcontaining about 50 to 70 weight percent polyphenyl-polymethylene polyisocyanate and &from 30 to 50 weight percent diphenyimethane diisocyanate, based or. the weight of all polyisocyanates used.

rrequetntly, so-called modifled muitivale--,t isocyanates, i.e., products by the partial chemical reaction of organic - diisocyanates and/or polyisocyanates are used. Examples include diisocyanates and/or polyisocyanates containing ester groups, urea groups, biuret groups, allophanate groups, carbodiimide groups. isocyanurate groups, and/or urethane groups. Specific examples include organic, preferably aromatic, polyisocyanates containing urethane groups and having an NCO content of 33.6 to 15 weight percent, preferably 31 to 21 weight percent, based on the total weight, e.g., w4th low molecular weight diols, triols, dialkylene glycols, trialkylene glycols, or polyoxyalkylene glycols with a molecular weight of up to 6000; modified 4,4-diphanylrnethane dlisocyanate or 2,4- and 2,6- toluene diisocyanate, where examples of d-4- and polycxyalk-ylene glycols that may be used dually or as mixt-are-s include diethylene glycol, dipropyiene glycol, polyoxyer-hylene glycol, 23 P01yoxyProPylene glycol, polyoxyethylene glycol, polyoxypropylena glycol, and polyoxypropylene polyoxyethylene glycols or -triols. prepolymers Containing NCO groups with an NCO content of 29 to 3 - 5 weight percent, preferably 21 to 14 weight percent, based on the total weight and produced from the polyester polyols and/or preferably polyether polyols described below; 4,4'-diphenylmethar.e diisocyte, mixtures of 2.41- and 4,41-diplienylmethme diisocywate, 2,4,- and/or 2,6-toluene diisocyanates or polymeric HD1 are also suitable. Furthermore.

liquid polyisocyanates c=talging carbod4-im,.de groups having an NCO content of 33.6 to l$ wight percent, preferably 31 to 21 weight percent, based m, the total weight, have also Jtable, e.g., bazo&on 4,4'- and 2,41and/or proven sui. 2,21-diphenylmethane diisocynate and/or 2,41- andlor 2,6- toluene diisocyanate. The modified polyisocyanates may optionally be mixed together or mixed with-.=wcUfied organic polyisocyanates such as 2,41- and 4:41-diphlmethane diisocyanate, polymeric MD1, 2,41- and/or 2 6toluena diisocyanate.

1 1 7 - The organic isocyanates usad-lz the invention preferably have an average - functionality of graater than 2, most preferably 2.5 or more.This provides for a ter crosslink....ng densIty in the resulting foam, which impro"a the dimensional stability of the f oam.

To produce the rigid close&' c11 polyu-vetha--e f oams of the present invention, the orq polyisocyanate and the isocyanate reactive comz)ounds are robacW in such amounts that the isocyanate index, defined number of equivalents of NCO groups divided by the total hydroge-,i atom equivalenu to less than about 150,-..- - The polyol composition of in the processing window composition and the dim of the resulting foam are a wide range of isocyanate er of isocyanate reactive -plied by 100, ranges from about -=ably from about 90 to 110.

Invention provides!lexbility t the solubility of the polyol stability and thermal insulation tantially unaffected throughout dices. If the rigid foams contain, at least in part, bonded ---rategroups, an isocyanate index of 150 to 6000, preferably, 200 to 800, is usually used.

AW, 10.

24 in a method of the invention, there iS provided the reaction of an organic isocyanate with a polyester polycl composition wherein the pOlyol composition comprises:

a) a phthalic anhyd=ide polyester polyol preferably having a hydroxyl number of 200 meq. polyol/q KOE or more.

b) a blowing agent selected from the group consisting C4-C6 hydrocarbons and mIxtures thereof; and c) an oxyethylated fatty acid or fatty alcohol compatibiliz--ng agent having an = of from about 7 to about 12.

optionally, but preferably, the hydrocarbon based blowing agent is is dissolved in the polycl composition. in one embodiment, the polyol composition contains the blowing agent in solution prior to reaction with the organic -socyanaA".e. Preferably, the organic isocyanate and the polycl composition are reacted at isocyanate =dices ranging from 30 to 350. All throughout this range the K-factors of the foam are substantially constant and the úoams are dimensionally stable. A substantially constant K-factor value means that the variance in values is 2J10 percent or less between the lowest and highast values within the range. Throughout the range, the foam also remains dimensionally stable as defined below. The measurements for the K- facto_--- are taken from core samples as described below in the definition of a dinens.:ionally stable foan, and are the initial K- factors.

The rigid foams made from polyisocyanate polyaddition products are advantageously produced by the one-shot process, for example, using reaction injection moldings, or the high pressure or low pressure method, in an open or closed mold, for example, in a metallic mold, or in a pourin-place application where, the surfaces contacting the reaction mixture become a part of the finished article. in a preferred embodiment, rigid foams may be made in a continuous laminate process, which process is well 1Clow in the industry.

The starting components may be mixed at from ISOC to 900c, preferably from 20C to 35C, and introduced into the open or closed mold, if desired under super-atmospheric pressure. The mixing of the isocyanate with the polyol composition containing dissolved blowing agent can be carried out mechanically by means of a sti=re= or a stirring sc=ew or under high pressure by the impingement linjection method. The mold temperature is exped-Lently I- from 20C to 1ICC, preferably from 30C to 604C, in particular from 450C to SCC.

The rigid foams produced by the process according to the invention and the corresponding structural foams are used, for example, in the vehicle industry -- the automotive, aircraft, and ship build....ng industries -and in the furniture and sports goods industries. They are particu larly suitable in the cons t_ruct-ion and refrigeration sectors as thermal insulators, for example, as intermediate layers for laminate board or for foam-filling ref=rigerators, fxeezer housirWa, and picnic coolers.

For pour-in-place applicatiMs, the rigid foam may be poured or inj acted to f orm a sandwich jkructure of a f irs t substrata/foam/second subst 2 or may be laminated over a substrate to form a substrat foam structure. The first and second substrate may each be Independently made of- the same material or of dif ferent materials, depending upon the end use. 77 Suitable substrate materials m-,grr;lrise metal such as aluminum, tin, or formed sheet metal &Uth as used in the case of refrigeration cablnets; wo cluding composite wood; acrylonil",,.rile-butadiene-st (ABS) triblock of rubber, optionally modified with styrne-butad-4ene diblock, tyrene- ethyl ene /butyl ene-styrene triblock, optionally functionalized with maleic 4hhydride and/or maleic acid, WlYcarbonate, polyaceals, rubber polyethyle.ne teraphthalate, modified high impact polyst"- (FLIPS). blends of HIPS with polyphenylene oxide, copol of ethylene and vinyl acetate, ethylene and acrylic acid, ---1en.e and vinyl alcohol, homopoiymers or. copolymers ethylene and propylene such as polypropylene, high densi v,--ilyethyler.e, high molecular weight high density polyethyllena, nyli. chloride, nylon 66, or amorphous thermoplastic tin, ABS, HIPS, polyethyl %t The polyurethane foam may Inner SU-"lAaces of the firs polyurethane foam may be ars. Preferred aze aluminum, jad hIgh density polyethylene.

tiquous to and bonded to the second substrates, or the quous to a layer or lamina of synthetic material inte.-pot#-between the substrates. Thus, the sequence of layers in the ite may also conmr..;kse a first subs %.i-ate/polyurethar.e foyer or laminalsecond substrate or first substrate/layez a/polyuzethane ioaznllayez or lami.na/second substrate.

The laye_--- or lamina of la additionally interposed into the composite may comprise any-" of the above-mentioned synthetic resins which have good 1^ tion such as low de-nsity 7W7 26 polyethYlene Or low dal.lsity linear polyethylene as a stress relief layer or a material which promotes adhesion between t.he polyurethane foam and the first and/or second substrate of choice.

when a synthetic plastic material such as polyathylene having few or no bonding or adhesion sites is chosen as the first and/or second substrate as an alternative to an adhesion-promoting layer, it is useful to first modify the substrate surface with a corona discharge or with a flame treatment to improve adhesion to the polyurethane foam.

I)uring the foam-in-place operation, the substrates are fixed apart in a spaced relationship to define a cavity between the first substrate and second substrate, and optionally the in-ner surface of at least one substrate, preferably both, treated to promote adhesion. This cavity is then filled with a liquid polyurethane system which reacts and foams In situ, bonding to the inner surf-aces of the first and second substrates. in the case of a refrigeration unit or a cooler container, such as a picnic cooler, a therrmoformed inner liner material is inserted into the outer shell of cooler or the refrigeration cabinet, - 1'n a nested spaced relationship to define a cavity, which cavity is then filled with a foamed-in-place polyurethane foam. In many cases, it is only the polyurethane foam which holds together the outer shell and inner liner, underscoring the need for foam dimensional stability.

The polyurethane cellular products of the invention are rig-,d, meaning that the ratio of tensile strength to compressive strength is high, on the order of D.5:1 or greater, and having less than 10 pez-cent elongation. The foams are also closed cell, meaning that the number of open calls J1.s 20% or less, - or conversely the number of closed cells is 80% or greater, the measurenent being taken on a molded foam packed at 10% over the theoretical amount required to fill the mold with foam.

The rigid polyurethane cellular products of the invention are dimensionally stable, exhibiting little or no shrinkage, even at free rise densities of 2.0 pcf or less. Z=. a preferred ezbod,,;.merit, the rigid polyurethane cellular products of the nvention tested according to ASTM D 2126-87 using core samples of density 2.0 pc! or less with dimensions of 30 x 3m x i and taken from a 10% parked boxes measi-,r:ing 40 X 10' X -10" advantageously have the following dimensional changes at 28 days of exposure: at 100 F/100 percent RE, i.e., relative humidity, no more than -'- 5 percent, more preferably no more than:t 3 percent; is 27 at 158 F/100 percent PUR no more than percent, most preferably less than:t 4 percent; at 158 F. dry no more than 8 percent, preferably no more than dt 6 percent; at 200 F, dry no more than.-j- 5, preferably no more than 3 percent; and at -20 F after 7 days exposure no more than:t 5 percent, preferably no more than t 3 percent.

-, k The thermal insulation valuclk':of the rigid closed cell foams according to the preferred Wbodiments of the invention are 0.160 BTU-in./hr.-ft2-F or loss initial, more preferably 0.150 or less initial, measured f the core of a 10% overpacked - sample. it has been found ttt foams made with the phthal ic-anhydride- initiated- polyester polyols exhibit relatively low k-factors.

in a pref erred einbodiment, the rigid polyurethane foams are also advantageously not friable tt their surface in spIte of their low dersity and the presence of polyols having a high hydroxyl number and low equivalent weight. IM&e foams typically exhibit a surt'ace friability of less thin 5 percent when tested according to AST.M C 421. at core Aema"-5 of 2.0 pcf or less, even at core densities of 1.5 pef or low surface friability ana les the foam to adhere well to &Mtrates.

The term polyisocyanata baim-,--dloam as used herein is _meant to include polyurethane-poly iit-poiyurethane-polyisocyanurate, polyurethane, and poly4- 0:121ate f oams.

The following examples ill te, the nature of the invention with regard to the formati composit,.or.s and the resu prepared therefrom. The to demonstrate the objects considered as limi tations all parts are expressed in EXAMPLES

Isocyanate A is a polymet having a free NCO conten' functionality of about 3 polyester Polyol is a ph poiyol having a nominal f number of about 240.

stable polyester PO1YO1 isocyanate-based rigid foam a presented herein are intended invention but should not be to. TjnIess otherwise indicated, by weight polyphenylene polyisocyanate ut 31 percent, a nominal viscosity of 700 cP at 259C.

anhydride-initiated polyester lity of about 2 and hyd=oxyl --- 28 Flame Retardant is a a tris(ChlOrO PrOPY1)Phosphate.

surfactant is a silicone surfactant polymer.

Catalyst is a potassium octoate catalyst in a dipropylene glycol carrier.

is Compatibilizer is a long chain tatty acid initiated oxyethylate having or. average about 8 ethylene oxide units per molecule and an 1MB of about 10.

Commercial cyclopentane is a product containing between about 80 and 850.. cyclopentane isomer which is commercially available from Phillips 66 Company.

pure cyclopentane, is a high purity reagant grade cyclopentane product commercially available from E=on Corporation containing greater than about 90% cyclopentana isomer.

Procedure tow Resin Bland: The amount of polyester polyal is weighed and placed into a glass bottle. The desired quantity of surfr-actant, catalyst. compatiblizer and flame retardant are added into the glass bottle container. Ge=erally, the components may be added in any order. The desired amount oú hydrocarbon blowing agent is dispensed into the glass contalner. The contents are sealed by tighter-ing the cap on the bottle. The contents are then mixed by vigorously shaking the bottle. The contents are allowed to remain at rest for 5 days at room te=.arat.=e without agitat-lon. T-fr upon visual inspection there is no phase separation (clear resin blend) such that two discrete layers are formed. the blowing agent is deemed soluble In the polyol composition, and the polyol composition is deemed storage stable.

Procedure for Production Of Polyurethane Foam: The polycl composition is then reacted with an amount of Isocyanate A at a foam index ratio of 300 such that the calculated ratio of NCO groups in the isocyanate is three times the number of hydr-oxyl groups in the resin components. The isocyanate is mixed and reacted with the resin blend at about room temperature using a high speed propeller mixer. Gas loss for these handmixes is determined according to the following procedure.

Procedure for gas loss determination: Supplies required: polypropylene tubs (approximately 8R in diameter and low in height) with h' drain tubes located about %-R below the open rim of the tub; laboratory balance; barometer; thermometer; water; and foam -,n-,xi. ng equipment (high speed propeller mixer). Place a 29 polypropylene tub on the laboratory balance and tare the balance Fill the polypropylene tub with water above the drain tube and allow it to drain until draining stops. Record the water weight needed to fill the tub. Record the water temperature. Repeat at least te-n times and calculate the average water weight needed to fill the tub. Empty the water from the tub and dry it out. Coat the inside of the tub with a release agent, such as paste wax to ease removal of foam. Place the tub on the balance and tare the balance. mix a foam handmix using normal laboratory technIque.

Pour approximately 200 grams.of mixed foam into a polypropylene tub and immediately record the weight of the foam before it starts to rise. Note: Exact wts are not =iticai in this operation. speed is. Dump the quickly into the tub and -eúcl the weight of the liquid on the balance as quickly as possible.

Allow the foam to rise in.the tub. Note: The foam should not rise above the level of the drain. Af ter several minutes, the foam weight will stabilize. Awo=d this value. Tare the balance to zero. Fill the tub with wa, above the drain tube and allow it to drain until it stops. Rd the weight of the water in i - the tub. Record the water t ture. Remove foam from the tub. Measure and record the bar=atzic pressure, the ambient air temperature and the wet bulb -temperature. Calculate the gas loss for each foam using the equations appearing below Tahjal.

Results: Samples 2; and 4; an& A-9; and 11-14; and 16-17; and 19-20 exhibit an improvement . >ercentage oo gas loss during the process of producing a polyuxe foam over Samples 1; and 3; and 5; and 10; and 15; and 18,--apectively. Further, Table 1 30 demonstrates the approximate 1 of compatibilizing agent _4.oplayed using different blowing PO yester polyol composition_ tion.

required f or the compositio= agents to provide a storage &W in accordance with the pres TABLE 1 ua- 1 2 3 4 5 6 1 7 8 9 in 11 1 12 13 14 15 16 17 18 19 20 Folyosie[Foly-ol-. 10 WO 1-0-0.0 MM Flame Reta#dani -mu.o 100.0 100.0 100.0 1000 1 100,0 16.0 7M 10.0 7M to.O --lw to 0 -TW -1w too Surfactant 7W -TW 7W 10.0 15.0 ' 10.0 10,0 7W -TW 1 2.0 -TU- --M --YU- yd- -TZ- -15- -7.U_ 2,0 2.

Catalyst TO- -YO- --M 2.0 -YW_ -YW- -T5- -M 2.0 -TW- -M -M --M -M -M -M n-- --71- 2.5 2.5--- --M 2.5 2.5 2.5 2.5 M_ -73--- 2.5 Compafjbgizer 0,0 -5.0 0.0 5.0 0.0 6.0 10-0 16A -50 10.0 15.0 20D OA 50 0- 0 0.0 10.5 COMMERCIAL. 25.0 25,0 - - - - - - CYCLOPENTANE PURE CYGUMPM-- TANE - 25.0 25.0 - - - - ISOPENTANE NORMAL PEMW 250 25.0 - - - - (NP) - - 25.0 250 25.0 25.0 25.0 C1:571p OWN0 GPINP BLEND MW- 10M -fjn,--lwm 1.99.5 i]W-igw 1593 -TT.T 199.5 159.5 tgb 25.0 CLEAR RESIN ULt:NU Yt:U YtS YLS Ye:s NU NO YES- NO NO Blowing Agent Loss = Wt. liquid foam ^ Wt. cured foam - Density atrbiont air 1 (Wt - total water Partial water) 1 (1)ensity water x 1000)l where: Density amblent air (M91 lent.1. x Bar.Press.) 1 1.362833 (Temp. dry buW + 460) MW ami.nt air = (28.964 x Dry Mole Fraction) + (0.19 x Absolute Moisture airblent air) Dry Mole Fraction = 1 - (Absolute Moisture ambient air 1 100) Absolute Moistureamblent air = [Vap. Press water 0 wet bulb t - (3.67 X 10-2) (Bar. Press.) (tremp.d Y Temp.wet bulb) R+(Temp-wet bulb-32)/1571)] 1 Bar.Press. K bu lb 1 1 W C0 33.

Claims (1)

1. CIAIMS

   1. 1. A Process for Producing an isocyanate-based rigid foam comprising reacting a) an arganIc and/or modified organic polyisocyanata with b) a polyol composition wherein said polyol cOM"SúUon comprises a phthalic anhydride- L-ii tiated Polyt Polyol, a fatty acid or fatty alcohol ethoxylate compat$Wizing agent having an EmB of from about 7 to about 12,',--- a blowing agent selec ad from is the group consisting of CA-Q hydrocarbans and mixtures thereof, and, optionally, a relatively low molecular weight chain extender or crossli. a surfactant, a catalyst and further auxiliaries andlor--,additives, wherein said blowing agent is soluble in the po composition.

   2. A process as defined in cl 1, wherein the compatibilizing agent is selected from the-Woup consisting of oxyethylated fatty acids of the general-2o=aula Rn-COO(E0)xE and mixtures thereof, wherein Pla is a CU to C26 alk-Yl chain, EO represents an ethylene oxide unit, and.-z is from about 5 to about 12.

   3. A process as defined in clato 1, wherein the compatibilizing agent comprises a Cla-Cao fy acid initiated oxyethylate having ar. average of about 8 ethylene oxide units per molecule.

   4. A process as defined in cl" 1, wherein the compatibilIzing agent is present in an of from about 1.0 to about 25.0 parts by weight based 4a 100 parts by weight of the polyester polyol.

   5. A process as defined in cl 1, wherein the compatibiliz,.-ig agent is present in an anKnoWof from about 5.0 to about 15. 0 parts by weight basedIW- 100 parts by weight of the polyester polycl.

   6. A process as defined in cl&L&t3, wherein the compatibilizing agent is present in an a=uat of from about 5.0 to about 15. 0 parts by weight ba3cd m 100 parts by weight of the 45 polyester polycl.

   IL.

   32 A process as defined in claim 1, wherein the polyester polyol has an hydroxyl number of 200 meg polyol/g KOE or mo-re.

   8. A process as defined in claim 1, wherein the amount of blowing agent is at least about 5.0 parts by weight based or- 100 parts by weight,of the polyester polyol.

   A process as defined in clatm 1, wherein said blowing agent is selected from the group consisting of isopentane, normal pentane, neopentane, cyclopentana and mixtures thereof.

   10. A process as def ined in claim 1 wherein the blowing agent further comprises water in an amount of from about 0.05 to 4 parts by weight based on 100 parts by weight of the polyester polyol.

   11. A process as defined in claim 1 wherein the polyol composition further comprises aromatic or aliphatic amine initiated polyaxyalkylene polyether polycls or polyester polyols other than the phthalic anhyd-ride initiated polyester polyol in an amount of less than about 20.0 weight percent based on the weight of all polyol components in the polycl composition.

   12. A process as def ined in claim 1 wherein the polyclcomposition further comprises assistants and/or additives.

   13. A process for producing an isocyanate-based rigid foam comprising reacting a) an organic and/or modif _Jed orgarilc polyisocyanate with b) a polycl composition wherein said polyol composition comprIses a phthalic anhydride-iniriated polyester polyol, a fatty acid or fatty alcohol ethoxylate compatibilizing agent having an w-,B of from about 7 to about 12, and a blowing agent comprising a Cshydrocarbon, and, optionally, a relatively low molecular weight chain extender or crosslinker, a surfactant, a catalyst and further auxiliaries and/or additives. wherein said blowing agent is soluble in the polyol composition.

   33 is 14. A process as defined in claim 13, wherein the compatibilizing agent is selected from the group consisting of oxyethylated fatty acids of the general formula R=-COO(B0).K and mixtures thereof, Where-'n Ra is a C14 to C26 alkyl chain, EO represents an ethylene oxide unit, and X is from aboulk 5 to about 12.

   15. A process as defined in claim 13, wherein the.compatibilizing agent comprises a Cle-C2o Urty acid initiated oxyethylate having an average of abou, 8 ethylene oxide units per molecule.

   16. A process as defined in CitIM 13, wherein. the corr.pat4-bil,.zing agent is present in an at of from about 1.0 to about 25.0 parts by weight basq-k--cn 100 parts by weight of the polyester polycl.

   17.

   A process as de!ined in claim 13, wherein the compatibilizing agent is present in an at of f rom about 5. 0 to about 15.0 parts by weight basiWi6n 100 parts by weight of the polyestar polycl.

   18. A process as defined in cliz 15, wherein the compatibilizing agent is present in an mt of from about 5.0 to about 15.0 parts by weight basci-6n in parts by weight of the polyester polycl- iia 1 19. A process as defined in c 13, wherein the blowing agent comprises a mixture of 1 tane and/or normal pentane ar.d cyclopentane.

   20. A process as defined in c4_Aim 13, wherein the amount of blowing agent is at least. t-ut 5. 0 parts by weight based no-"" on 100 parts by weight of polyester polyol.

   21. A process as defined in in an amount of from;;on 100 parts by weight Min 13 further comprising water 05 to 4 parts by weight based 0 polyester poiyol.

   Z 22. A process as defined in c 13, wherein the polyester polyol has an hydroxyl of 200 meg polycl/g KOE or a"5 MOre.

   I-1w I - - - 39. - is 23. A process for producing an isacyanate-based rigid foam comprising reacting a) an organic and/or modified organic polyisocyanate with b) a polyol composition wherein said polyal composition comprises a phthalic anhydride-initiated polyester polyol, a compatibilizing agent comprising a CU-C2. fatty acid initiated oxyethylate having an average of about 8 ethylene oxide units per molecule and having an of about 10, and a blowing agent comprising isopentane and cyclopentane in a weight ratio of from about 30:70 to about 40:60, and, optionally, a relatively low molecular weight chain extender or crosslinker, a surfactant, a catalyst and further auxiliaries and/or additives, wherein said blowing agent is soluble in the polyol composition.

   24. A process for producing an isocyanate-based rigid foam as claimed in any of claims 1, 13 and 23 and substantially as described in any of the Examples.

   25. An isocyanate-based rigid foam comprising the reaction product of:- a) an organic and/or modified organic poly-isocyanate and h) a polycl composition wherein said polyol composition comprises a phthalic, anhydride-initiated polyester polyol, a fatty acid or fatty alcohol ethoxylate compatibilizing agent having an HLB of from about 7 to about 12, and a blowing agent selected from thegroup consisting of C4-C6 hydrocarbons and mixtures thereof, and, optionally, a relatively low molecular weight chain extender or crosslinker. a surfactant, a catalyst and further auxiliaries and/or additives, wherein said blowing agent is soluble in the polyol composition.

   26. A rigid foam as defined in claim 25, including the feature of any of the foregoing claims 2 to 12.

   jj. An isocyanate-based rigid foam comprising the reaction product of:

   a) an organic and/or modified organic polyisocyanate with b) a polyol composition wherein said polyol composition comprises a phthalic anhydride-Initiated polyester polycl, a fatty acid or fatty alcohol ethoxylate compatibilizing agent having an HU of from, about 7 to about 12, and a blowing agent comprising a CS hydrocarbon, and, optionally, a relatively low molecular weight chain extender or Crosalinker, a surfactant, a catalyst and further auxiliaries and/or additives, wherein said blowing agent is colUble in the polycl composition.

   :Sf- 28. A rigid foam as defined in claim 27, including the features of any of the foregoing claims 14 to 22.

   2Z. An isocyanate-based rigrio= comprising the reaction product of:

   a) an organic and/or woffified organic polyisocyanate with b) a polyol compositiont- wherein said polyol co tion comprises a phthalic anhydride-in.itiate polM'-- polyol, a Compatibilizing agent comprising a Cla-C2o fatty-AC:Ld-initiated oxyethylate having an average of about 8 c '...I c oxide units per molecule and U 1 "M having an HLB of about 1Or a blowing agent comprising isopentane and cyclopenta In a weight ratio of f rom about 30:70 to about 40:60, Cqptionally, a relatively low mole cular weight chain extenglWor crosslinker. a surfactant, a catalyst and further auies and/or additives, wherein @1 in the polyol composition.

   said blowing agent is 7- 30. An isocyanate-based ridM foam as claimed in claim 25 or 27 or 29 and Jtantially as hereinbefore described or exemplif:Led in any of the foregoing Examples.

   1 at 31G 31 A stable polyester polyol composition comprising:

   a phthalic anhydride-initiated polyester polyol, b) a blowing agent selected from the group consisting of C4-C6 hydrocarbons and mixtures thereof, and c) a fatty acid or fatty alcohol ethoxylate compatibilizing agent having an HLB of from about 7 to about 12, wherein said blowing agent is soluble in the polyol composition.

   32. A stable polyester polyol composition as defined in claim 31 and including the features of any of the foregoing claims 2 to 12.

   13. A stable polyester polyol composition comprising:

   a) a phthalic anhydride-initiated polyester polycl, b) a blowing agent comprising a C5 hydrocarbon, and c) a fatty acid or fatty alcohol ethoxylate compatibilizing agent having an HLB of from about 7 to about 12, wherein said blowing agent is soluble in the polyol composition.

   34. A stable polyester polyol composition as def ined in claim 33 and including the features of any of the foregoing claims 14 to 22 or 12.

   37 35. A stable polyester polYO1 composition comprising:

   a) a phthalic anhydride-initiated polyester polyol, b) a blowing agent comprising isopentane and cYclopentane in a weight ratio of from about 30:70 to about 60:40, and c) a compatibilizing agent comprising a C18-C20 fatty acid-initiated oxyethylate having an average of about 8 ethylene oxide unit per molecule and having an ELB of about 10, wherein said blowing agent is soluble in the polyol is composition.

   36. A stable polyester polyol composition as defined in claim 31 or 33 or 35 and substantially as hereinbefore described or exemplified in any of the foregoing Examples.

   f