CA1094241A - High molecular weight, insoluble carbodiimidization catalysts - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
The instant invention relates to novel carbodiimi-dization catalysts consisting of a high molecular weight, insoluble matrix, which is capable of swelling, and low mole-cular weight carbodiimidization catalysts fixed on, in, or to the matrix via convalent bonds. The novel high molecular weight catalysts are suitable for the preparation of storage stable, catalyst-free equilibrium mixtures of organic isocyanates, carbodiimides and uretone imines. Either the carbodiimide, or the uretone imine or both may contain isocyanate groups.
Alternatively, mono and/or polyisocyanates free from carbodi-imide and uretone imine groups may be added to the equilibrium mixture. The catalysts according to the invention are capable of bringing about selective carbodiimidization of individual isocyanates in a mixture of various isocyanates.

Description

Mo-1670-G
LeA 16,592 ~.O.~ Z~

HIGH MOLECULAR WEIGHT, INSOLUBLE CARBODIIMIDIZATION CATALYSTS

BACKGROUND OF THE INVENTION

Carbodiimides can be produced from isocyanates with phospholine oxides as catalysts in a particularly simple reaction even at room temperature based on the process disclosed in German Patent 1,130,594. The commercially most important and most effective catalysts, which carbodiimidize the aromatic mono- and polyisocyanates very quickly, even at room temperature, and can convert less reactive aliphatic or cycloaliphatic mono-and polyisocyanates into carbodiimides at temperatures aboveapproximately 150C are those of the general formulae R~/ 0~-- ~H

wherein R and R', which may be the same or different, represent aromatic or aliphatic hydrocarbon radicals with 1 to 14, and preferably 1 to 4 carbon atoms. R' can also represent a hydrogen atom.

These catalysts have already been used commercially for the preparation of polycarbodiimide foams ~elative to compounds of the formula Ic, see Journal of Organic Chemistry 32, 4066 (1967)).

Experience has shown that it is not possible to stop carbodiimide formation occurring in the homogeneous phase with the above-mentioned slightly soluble catalysts in such a way that storage stable, carbodiimide or polycarbodiimides LeA 16,592 containing isocyanate groups are obtained. It is likewise not possible to produce stable solutions of diisocyanato-carbodiimides, ~ diisocyanato-bis-carbodiimides, ~
diisocyanato-tris-carbodiimides or the isocyanateuretone imines, 5 such as those corresponding to the formula:

(II) H3C ~ N C -- -- N ~ 3 o C N NCO

~, - I NCO

in excess monomeric mono or polyisocyanates. Thus, the carb~diimidization under the influence of the catalytically hiqhly effective soluble phospholine oxides cannot be completely stopped with deactivation agents such as phosphoroxychloride, zinc chloride, dimethyl carbamic acid chloride, benzoyl chloride, hydrochloric acid, boron trifluoride, alkylation agents and the like, with the result that high molecular weight, insoluble, low quality products are produced. As a result of progressive (and even though in some cases, slow) formation of carbodiimide, a high carbon dioxide pressure soon develops in cloud reaction and/or storage vessels, which may result in serious and danger-ous accidents.

DESCRIPTION OF THE INVENTION

Ithas now surprisingly been found that it is possible to bond carbodiimidization catalysts without any sub-stantial loss of their catalytic effect via covalent bonds on, LeA 16,592-G - 2 -in, or to a high molecular weight, organic matrix which is capable of swelling, but, which is insoluble in polyisocyanates.
In this way high molecular weight, insoluble catalysts capable of swelling are obtained, which can be removed at any time from the reaction mixture. It is thus possible to convert mono and preferably, polyisocyanates into storage stable carbodiimides or polycarbodiimides or the uretone imines thereof with functional NCO-groups. It is also possible to produce storage stable mixtures of (poly) carbodiimides or their uretone imines with polyisocyanates. One particularly surprising finding is that it is even possible to carry out selective carbodiimidization of certain mono- or polyisocyanates of an isocyanate mixture.

The object of the present invention is therefore to provide high molecular weight, carbodiimidization catalysts which are insoluble in polyisocyanates, and which consist of a high molecular weight matrix and a low molecular weight carbodiimidization catalyst covalently bonded in, on, or to this matrix. The preferred low molecular weight carbodiimi-dization cataly~t are the saturated or unsaturated 5-membered or saturated 4-membered cyclic phosphinic oxide.

The molecular weight of the matrix according to the invention is generally above 2000. According to the invention highly cross linked products are preferably used.

The present invention also relates to a process for the production of such catalysts characterized in that a high molecular weight matrix having functional groups or monomers suitable for the construction of a high molecular weight matrix are reacted with low molecular weight carbodiimidization catalysts or precursors thereof, which LeA 16,592 - 3 -109424~

contain groups reactive towards the functional groups of the matrix or the monomers.

For the production of the high molecular weight carbodiimidization catalysts according to the invention, basically any known low molecular weight carbodiimidization catalysts or precursor thereof are suitable. These precursors are generally converted into the catalytically effective form when incorporated into the matrix. The known low molecular weight carbodiimidization catalysts must where necessary for incorporation into the high molecular weight matrix be modified by functional groups, which can react with the matrix or the monomers used for the preparation of the matrix.

The coupling between the low molecular weight carbodiimidization catalysts and the high molecular weight matrix can be effective via essentially any covalent bond such as carbon-carbon bonds, ether, ester, urethane, amide, sulphide groups and the like. The preferred couplings are ester groups and, most preferred are aliphatic carbon-carbon bonds.

The preferred low molecular weight catalysts according to the invention are cyclic phosphinic oxides of the above-described type (formula Ia) and cyclic phosphinic oxides derived therefrom. These materials may, in addition, exhibit ring substituents with functional groups for uniting covalent bonds, for use as low molecular weight carbodiimidization catalysts for the production of the high molecular weight carbodiimidization catalysts according to the invention.

A further preferred type of low molecular weight catalysts for the production of the high molecular weight carbodiimidization catalysts according to the invention are the Le~ 16,592-G - 4 -1(~9~

cyclic phosphinic oxides of the general formula (Ib). These contain at the ring or at the phosphorus atom, alkyl, aryl or aralkyl substituents with functional groups, by which covalent bonds can be coupled to the polymeric matrix.

5Compounds of this type are, for example, those of the general formula R4 (IIIa) R4 R3 R4 H

U ~RlR2R3 ~R RSJ ~U (IIIb) OH H OH
R4 ~f R3 H ~ 2 ( I I IC ) in which Rl represents halogen, an alkoxy group, aryloxy group with up to 14 carbon atoms or an amino group, which can be substituted with alkyl, alkenyl, aryl or aralkyl radicals with up to 14 carbon atoms, or an alkyl, alkenyl, aryl or aralkyl radical which may have an amino or hydroxyl group, with up to 14, and preferably 1 to 4 carbon atoms and R2; R3; R ; R5 represents hydrogen, halogen, a carboxyl group, Cl - C14, preferably Cl - C4, alkyl or alkoxy carbonyl radicals, phosphonic acid ester - or Cl - C4 - alkoxy - or alkyl mercapto radicals, which may contain further functional groups such as olefinic carbon to carbon double LeA 16, 592-G - 5 -1(~94241 bonds, amino or hydroxyl groups.

Typical representatives of such compounds include:

2 V X ~ (CH2-CH - O) HX = O; S. (IV) /~ O~CH2-CH-O)bH R - H and/or CH3 H2 1 1 I~H (V) H I ~ I H (VI) H ~ O-CH2-CH=CH2 or 2 ~ 2 O CH3 CH2-CH=CH2 OH H
H ~ f OH OH
l (VII) H
H2 - ~--H2 H ~=¦~H
H/~H

H H O
H ~ 3 H ~ CH2 C~

H ~ H H ~ H OC2H5 LeA 16,592 - 6 -10~241 Low molecular weight catalysts of this type can be produced in the following way:

Compounds of the type (IV) are produced by reaction of a compound of the formula H

H2 ~ "_,~ O-H (X = O; S.) H2 ~ ~ H - O-H

with ethylene oxide or propylene oxide. The reaction takes place at 0 to 180C, preferably 50 to 150C, and can be carried out at both normal pressure and at increased pressure, and may also be carried out in an inert solvent.

Low molecular weight carbodiimidization catalysts .~- -alkyl substituted at the phospholane ring of the type (IV) can be obtained in a similar manner (see also German Offenlegungs-schrift 2,504,400).

Compounds of the type (V) can be obtained by reacting 15 compounds of the general formula R7 ~ R8 H2 ~ ~ R

in which R represents an alkyl or an aryl radical with up to 14 carbon atoms and R7,R8,R9 which may be the same or different represent a Cl to C4 alkyl radical or hydrogen with a compound of the general formula LeA 16,592-G - 7 -~94~41 in which R10 represents an alkyl, aryl or aralkyl radical with 1 to 14 preferably 1 to 4 carbon atoms, which may also contain other functional groups such as olefinic carbon to carbon double bonds, in the presence of alkaline catalyst.

Compounds of the type (VI) are produced by a reaction of the general compound R2 R3 [Izvestiya Akademi ¦ / NaukSSSR, Seriya ~ 1--, Khimischeskaya, No. 8 H l R4 pp. 1847-1848 2 ~ ~ ~ (further literature ~ \ therein)]

in which X represents a halogen atom (e.g. chlorine, bromine or iodine) and R2 R3 R4 which may be the same or different represent a Clto C4 alkyl radical or hydrogen, with an organometallic compound e.g. a Grignard compound of which the organic radical may contain the desired functional group such as olefinic carbon to carbon double bonds. Solvents generally used for this reaction include hydrocarbons and ether (T~F).

Compounds of the type (VII) are produced by the hydrolysis of 3,4-epoxyphospholane-1-oxides. (B. A. Arbusov, A. P. Rakow, A. O. Vizel, Izv. Akad. Nauk SSSR, 196~9. 2230 -2234).
LeA 16,592-G - 8 -1(~94Z~l In the high molecular weight catalysts according to the invention based on t:he compounds of formula I to III, the phosphorus content is in general between 0.05 and 23% by weight, and preferably between 0.3 and 8% by weight.

"Precursors" of the low molecular weight carbodi-imidization catalysts according to the invention include com-pounds of the type ~¦ ¦ ,' (see US Patent No.
(VIII) R3 ~ ¦ ~1 3,723,520) ~1 .

in which 0 Rl, R2 and R3 represent hydrogen or Cl - C 14' preferably Cl - C4, alkyl radicals and X represents halogen.

Such compounds can, for example, be incorporated into a high molecular weight matrix as illustrated in the following diagram with the formation of the catalytically effective cyclic phosphinic oxide grouping:

macromolecule ~
OH o -HX >

Heat ~ ,~
(Alkyl iodide as ~.
catalyst) ~

LeA 16,592-G - 9 -24~.

A further method of production using precursors the Arbusov-reaction:

Arbusov-~ reaction CH2X + RO-CH2-P~ l + RX
O \~

Further "precursors" of carbodiimidization catalysts are in addition, for example, compounds of the type R-PX2 (X = halogen), in which the radical - PX2 is bonded to an alkyl, aryl or aralkyl radical, which in its turn may already be part of a high molecular weight polymer. An example of this type is provided by the reaction products of PX3 with polystyrene.

Compounds R-PX2 can easily be converted into cyclic phosphinic oxides by reaction with dienes and subsequent hydrolysis:

(X) IrlL ~ H20 _~
lS \ p / ¦ 0~ R

LeA 16,592-G - 10 -Suitable polymers for use as the high molecular weight matrix for the catalyst according to the invention contain functional groups for a covalent bond coupling to the low molecular weight carbodiimidization catalyst. On the other hand it is, of course, also possible in the production of the catalysts according to the invention to start from monomers which, during polymerization to a high molecular weight product, incorporate the low molecular weight carbodiimidization catalysts having the suitable functional groups.

A preferred matrix for the catalyst according to the invention are unsaturated polyester resins. In this variation of the process according to the invention, dicarboxylic acids and diols are first condensed by known methods, with at least one of the components being unsaturated, to form an unsaturated polyester. Approximately 10 to 70% by weight based on the polyester, of a phospholine oxide are then added, which may contain a substituent with an additional olefinic double bond, and the mixture is heated together with reaction in~tiators.

Instead of the free dicarboxylic acid, according to the invention, the corresponding dicarboxylic acid anhydrides or corresponding carboxylic acid esters of low alcohols or mixtures thereof can be used for the production of the poly-esters. The carboxylic acids can be of the aliphatic, cyclo-aliphatic, aromatic and/or heterocyclic type and may be sub-stituted, for example, by halogen atoms. Examples which can be mentioned include malonic acid, succinic acid, adipic acid, suberic acid, azelaic acid, fatty acid, phthalic acid, isophthalic acid, trimellitic acid, phthalic acid anhydride, tetrahydrophthalic acid anhydride, hexahydrophthalic acid LeA 16,592-G - 11 -~(~94Z41 anhydride, tetrachlorophthalic acid anhydride, endomethylene tetrahydrophthalic acid anhydride, glutaric acid anhydride, maleic acid, maleic acid anhydride, fumaric acid, dimeric and trimeric fatty acids such as oleic acid, which may be mixed with monomeric fatty acids, ~rephthalic acid dimethyl ester and terephthalic acid-bis-glycol ester and any mixtures thereof. Diols to be considered include for example ethyl-eneglycol, propyleneglycol-(1,2) and -11,3)butyleneglycol-(1,4) and (2,3), hexanediol-11,6), octianediol-(1,8), neo-pentylglycol, cyclohexanedimethanol (1,4-bis-hydroxymethyl-cyclohexane), 2-methyl-1,3-propanediol, the isomeric butene-diols, diethylene-glycol, triethyleneglycol, tetraethylene-glycol, polyethyleneglycol, dipropyleneglycol, polypropylene-glycols, dibutyleneglycol and polybutyleneglycols.

Preferred acid components are malonic acid and esters thereof, maleic acid anhydride, maleic acid and its esters, fumaric acid and its esters and muconic acid and its esters.

Preferred diols are ethane diol, propane diol, and the polycondensates thereof (preferably up to a molecular weight of 400), butene diols, butane diols and mixtures of these diols.

Reaction initiators which are considered for the reaction of the polyesters with phospholine, phospholane or phosphetane oxide containing double bonds, include radical forming agents which are active in the temperature range of from 50 to 300C. Particularly useful are organic peroxides, aliphatic azo compounds and high energy radiation. Examples include dialkyl peroxides such as di-tert.-butylperoxide, diacylperoxides such as dibenzoylperoxide, p-chloro-benzoyl-LeA 16,592-G - 12 -1C~94Z~l peroxide, 2,4-dichlorobenzoylperoxide, succinylperoxide, non-anoylperoxide~ lauroylperoxide, peroxyesters such as tert.-butyl-peroctoate,tert.-butyl-periosbutyrate, tert.-butyl-peracetate, tert.-butylperbenzoate, tert.-butylperivalate and peroxyketals and percarbonates, azoisobutyric acid nitrile, azo-bis-isobutanol-di-acetate and ultra violet radiation, X-rays or gamma rays.

Catalysts based on polyesters according to the invention can also be produced by replacing a part of the diol component in the known preparation of polyesters by phospholine oxides or phospholane oxides of the above described type (formulae I, III, IV and VII) substituted with dihydroxy alkyl groups.

Of course the low molecular weight carbodiimidization catalysts can also be incorporated in a similar manner into other polycondensation or polyaddition resins via suitable functional groups (e.g. -OH, -NH2 or -COOH), e.g. in polyamides, polyurethane~ or epoxide resins.

It is also possible to produce high molecular weight cataly~ts according to the invention by incorporating low molecular weight carbodiimidization catalysts in, preferably, cross-linked polystyrene. Thus, for example, one of the compounds of the formula I, III or VIII can be copolymerized with styrene and, optionally, from about 1 to 10~ by weight of divinyl benzene, by means of the above mentioned reaction initiators.

A further method of producticn is to metallize a halogenated polystyrene (see Houben-Weyl XIV/2, 764 (1963)), preferably by means of tert.-butyl-lithium, and then to react it with a halogen-substituted phospholine or phospholane oxide, LeA 16,592-G - 13 -i(~94241 and preferably with a l-chloro-phospholine oxide.

Similarly to the above described method of preparation for compounds of the formula (V) it is also possible to add phospholine oxides preferably l-methyl-l-phospha-2-or-3-cyclopentene-l-oxide, to a matrix with anionic groups (e.g.
alcoholate groups to polyvinyl alcohol).

Catalysts according to the invention can also be produced via polymers functionalized with -PX2-groups (X = Cl, Br) e.g. copolymers of styrene and divinyl benzene (se~ for example Houben-Weyl XIV/l, p. 821 (1961)).

The catalytically active phospholine ring is formed by addition of 1,3-dienes e.g. 1,3-butadiene isoprene or 2,3-dimethyl-1,3-butadiene (see formula diagram X) at the phosphorus atom.

In a similar manner, of course, compounds of the formula I, III, or VIII which may contain further substituents with olefinic carbon to carbon double bonds or compounds of the type R-PX2 (X = Cl, Br) in which R represents an alkenyl radical, can also be copolymerized with other olefinic un-saturated monomers (e.g. ethylene, propylene, butene, butadiene, vinylchloride, vinylacetate, N-vinylpyrrolidone, etc.) and, in this way, be incorporated in a high molecular weight matrix.

Catalysts according to the invention, can also be obtained by heating a phospholine halide of the formula (VIII) (which can optionally also be saturated) with high molecular weight polyhydroxyl compounds, e.g. polyvinyl alcohols, optionally in the presence of bases, and with catalytic quantities of alkyl halides. In this process according to formula diagram IX the catalytically acting phospholine oxide LeA 16,592-G - 14 -1~4Z41 is produced at the matrix with the coupling of an additional carbon-phosphorus bond (U. S. Patent No . 3,723,520; Houben-Weyl XII/l, p. 150 (1963)).

By using the catalysts according to the invention basically any aliphatic, cycloaliphatic, araliphatic, aromatic and heterocyclic polyisocyanate can be carbodiimidized.
Suitable isocyanates are described for example by W. Siefken in Justus Liebigs Annalen der Chemie, 562, pages 72 to 136, and include ethylene diisocyanate; 1,4-tetramethylenediisocyanate;
1,6-hexamethylenediisocyanate; 1,12-dodecanediisocyanate;
cyclobutane-l, 3-diisocyanate; cyclohexane 1,3- and 1,4-di-isocyanate and any mixtures of these isomers; l-isocyanato-

3,3,5-tri-methyl-5-isocyanatomethyl-cyclohexane (German Auslegeschrift No. 1,202,785, U. S. Patent No. 3,401,190);
2,4- and 2,6-hexahydrotoluylenediisocyanate and any mixtures of these isomers; hexahydro-1,3- and/or-1,4-phenylene diisocyanate; perhydro-2,4'- and/or -4,4'-diphenylmethane diisocyanate; 1,3- and 1,4-phenylenediisocyanate; 2,4- and 2,6-toluylenediisocyanate and any mixtures of these isomerst diphenylmethane 2,4'- and/or -4,4'-diisocyanate; naphthylene-1,5-diisocyanate; triphenylmethane-4,4',4"-triisocyanate;
polyphenyl-polymethylenepolyisocyanates as obtained by aniline formaldehyde condensation and sub~equent phosgenation and for example described in Pritish Patents No. 874,430 and 848,671;
m- and p-isocyanatophenyl-sulphonyl isocyanates according to U. S. Patent 3,454,606; perchlorinated aryl polyisocyanates, as described in German Auslegeschrift No. 1,157,601 (U. S.
Patent No. 3,227,138); polyisocyanates having carbodiimide groups as described in German Patent No. 1,092,007 (U. S. Patent No. 3,152,162); diisocyanates as described in U. S. Patent No. 3,492,330; polyisocyanates having allophanate groups, as LeA 16,592-G -15-for example described in British Patent No. 994,890; Belgian Patent No. 761,626 and Published Dutch Patent Application No. 7,102,524; polyisocyanates having isocyanurate groups, as for example described in U. S. Patent No. 3,001,973;
German Patents No. 1,022,789, 1,222,067 and 1,027,394 and German Offenlegungsschriften No. 1,929,034 and 2,004,048.
Polyisocyanates having urethane groups as for example described in Belgian Patent No. 752,261 and U. S. Patent No. 3,394,164;
polyisocyanates having acylated urea groups according to German Patent 1,230,778; polyisocyanates having biuret groups, as for example described in German Patent No. 1,101,394, U. S.
Patents No. 3,124,605 and 3,201,372 and British Patent No.
889,050; polyisocyanates produced by telomerization reactions, for example as described in U. S. Patent No. 3,654,106; poly-isocyanates having ester groups, as for example described in British Patents No. 965,474 and 1,072,956; U. S. Patent No.
3,567,763 and German Patent No. 1,231,688; reaction products of the above mentioned isocyanates with acetals according to German Patent No. 1,072,385 and polyisocyanates containing polymeric fatty acid radicals according to U. S. Patent 3,455,883.

It is also possible to use the distillation residues having isocyanate groups which occur in commercial isocyanate production, optionally dissolved in one or more of the above mentioned polyisocyanates. In addition it is possible to use any mixtures of the above mentioned poly-isocyanates. Aromatic polyisocyanates preferred according to the invention are 2,4-toluylene diisocyanate, 2,6-toluylene diisocyanate and any mix*ures of these isomers, m-phenylene-diisocyanate, p-phenylenediisocyanate and approximately 10 to LeA 16,592-G - 16 -1~94Z4~

40~ by weight solutions of biuretization, allophanatization, urethanization, trimerization and dimerization products of these polyisocyanates in monomeric polyisocyanates, and in particular in monomeric toluylene diisocyanate.

Of the aliphatic, cycloaliphatic,araliphatic polyisocyanates, tetramethylenediisocyanate; pentamethylene-diisocyanate; hexamethylenediisocyanate; dicyclohexylmethane-diisocyanate; l-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane; lysinesterdiisocyanates; m- and p-xylylene-diisocyanate and mixtures thereof are preferred, as are the solutions of their biuretization and dimerization products in the corresponding monomeric polyisocyanates.

Naturally, monoisocyanates can also be carbodiimidized.
Suitable monoisocyanates are for example methyl isocyanate;
ethyl isocyanate; propyl isocyanate; isopropyl isocyanate;
diisopropylphenyl isocyanate; n-butyl isocyanate; n-hexyl isocyanate; ~-chlorohexyl isocyanate; phenyl isocyanate;
tolyl isocyanate; p-chlorophenyl isocyanate; 2,4-dicloro-phenyl isocyanate and trifluoromethylphenyl isocyanate.

The carbodiimidization of these mono and poly-isocyanates or their mixtures is carried out so that the isocyanates which may be dissolved in inert solvents such as toluene; xylene; chlorobenzene; o-dichlorobenzene; decalin;
dimethylformamide; dimethylacetamide; butylacetate; carbon tetrachloride; trichloroethylene and tetramethylurea, are brought into contact with, preferably 0.2 to 10% particularly preferably 1 to 4% by weight of the matrix charged with catalyst molecules based on the isocyanates at a temperature of between approximately 50and 200C, preferably 80 to 185C
and optionally under pressure. This reaction is carried out LeA 16,592-G - 17 -1~94Z41 in the simplest manner so that the catalyst is introduced into the liquid or dissolved isocyanates under agitation and, after reaching the desired degree of carbodiimidization is removed by decanting or filtration. The degree of reaction can be easily followed by measuring the volume of the carbon dioxide generated during the carbodiimidization reaction. The catalysts according to the invention can generally be reused more than 10 to 20 times without affecting their effectiveness. Of course it is also possible to conduct the carbodiimidization contin-uously in a column, provided that a suitable arrangement ismade for the unhindered escape of the carbon dioxide formed in the reaction.

Naturally, the carbodiimidized mono and/or poly-isocyanates produced according to the invention can subsequently, if desired only partially be mixed with further polyisocyanates.
In this way, storage stable mixtures of high and/or low mole-cular weight polyisocyanates can be produced with high and/or low molecular weight carbodiimides or uretone imines which may have isocyanate groups.

Since the carbodiimidization catalysts according to the invention can be completely removed after the reaction in contrast with the hitherto known catalysts, in principle, mixtures with any carbodiimide group content can be produced.
However, according to the invention preference is given to mixtures which contain approximately 3 to 70% by weight, especially preferably 10 to 60% by weight, of carbodiimides, polycarbodiimides or uretone imines. As is well known in the art, uretone imines are addition compounds of a carbodi-imide and an isocyanate. The following polyisocyanate/
carbodiimide-mixtures are of particular commercial importance:

LeA 16,592-G - 18 -1~94Z4~

a) A mixture of lO0 parts by weight of 4,4'-diisocyanato-diphenylmethane and/or l,S-naphthylene diisocyanate and 5 to 30 parts by weight of an equilibrium mixture of the diisocyanatocarbodiimides of the toluylene diisocyanate and the corresponding triisocyanatouretone imines.

b) Mixtures of 100 parts by weight of 4,4'-diisocyanato-diphenylmethane and/or 1,5-naphthylene diisocyanate and 10 to 30 parts by weight of an equilibrium mixture of carbodiimides of phenyl isocyanate, hexamethy-lenediisocyanate, tetramethylene-diisocyanate, cyclohexylisocyanate or tolylisocyanate and lS the uretone imines thereof.

c) Mixtures of 100 parts by weight of toluylene diisocyanate and 5 to 30 parts by weight of an equilibrium mixture of carbodiimidized phenyl isocyanate or tolyl isocyanate and the uretone imines thereof.

d) A mixture of lO0 parts by weight of modified toluylene diisocyanate, containing lO to 40%
by weight of biuret allophanate, urethane or isocyanurate polyisocyanates based on toluylene diisocyanate and lO to 20 parts by weight of an equilibrium mixture of toluylenediisocyanato carbodiimide and the corresponding triisocyanato uretone imine.

LeA 16,592-G - 19 -~(~'3~Z4~

e) A mixture of 100 parts by weight of a biuret polyisocyanate of hexamethylene diisocyanates (preferably reaction products from 1 mol water and approximately 2 to 3 mol hexamethylene diisocyanate) and 10 to 30 parts by weight of an equilibrium mixture of the carbodiimide of hexamethylene diisocyanate and the corresponding uretone imine poly-isocyanates.
f) Mixtures of 100 parts by weight of an a,~ -diisocyanato prepolymer (obtained from 1 mol a,~ - dihydroxypolyesters or polyethers of the type known in the art and 1.4 to 2.5, preferably 1.6 to 2 mol toluylene diisocyanate, diisocyanato-lS diphenylmethane or hexamethylene diisocyanate) and 5 to 30 parts by weight of an equilibrium mixture of carbodiimides, or carbodiimide diisocyanates and the corresponding uretone imine polyisocyanates of phenyl isocyanate, tolyl isocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate or toluylene diisocyanate.

The carbodiimides which may have isocyanate groups which are produced with the catalysts according to the invention and the solutions thereof in carbodiimide group freepoly-isocyanate are valuable starting products for the diisocyanate-polyaddition process and can be used for the production of greatly varying hard to elastic, optionally cellular, plastics for the production of lacquers, coverings, coatings, films and LeA 16,592-G - 20 -1(~94;~1 moldings. Polyurethanes produced in this way contain, in the polymer molecule, permanently incorporated carbodiimide groups and uretone imine groups (= masked carbodiimide groups), which at the same time constitute anti-ageing agents against the hydrolysis of ester bonds and, in addition, reduce the inflammability of the plastics material.

The production of polyurethane takes place in a known manner by the react:Lon of the polyisocyanatemixtures with high and, optionally, also low molecular weight compounds, having at least two hydrogen atoms capable of reacting with isocyanates.

The following Examples illustrate the present invention.
Unless otherwise specified, all figures are to be understood as parts or percentages by weight.

LeA 16,592 - 21 -1(~94Z41 a) 70 parts by weight of a polyester having an acid number of approximately 8 (produced from 406 parts by weight maleic acid anhydride and 438 parts by weight diethylene glycol) are heated slowly with 30 parts by weight l-methyl-l-phospha-2 and 3-cyclopentene-1-oxide (l-methyl-phospholine oxide) in the presence of 1.5 grams benzoyl peroxide under agitation to 150C. At 110C a solid, crumbly product is produced. After extraction of residual monomers, first with toluene and then with chloroform, the polymer contains 1.25 by weight of phosphorus.

b) Example la is repeated, but with the addition of 3.5 parts by weight styrene to the reaction mixture. A rather harder product is obtained, having a phosphorus content of 0.5% by weight.

25 parts by weight of the catalyst of Example la and 40 parts by weight of toluene are added to 34.8 parts by weight of an isomer mixture of 2,4- and 2,6-toluylene -diisocyanate (80 : 20) and heated to 110C. After 1 hour, 3.6 liters of carbon dioxide had been generated and the isocyanate content of the solution of the isocyanate mi~ture had fallen to 8.6% by weight.

a) 35 parts by weight of an unsaturated polyester [from 1 mol maleic acid anhydride and 1 mol tetraethylene glycol (acid number 9)] are mixed well with 15 parts by weight 1-methyl-l-phospha-3-cyclopentene-1-oxide and 0.7 parts by weight benzoyl peroxide and slowly heated under agitation to 150C.

LeA 16,592-G - 22 -1~94Z41 The crumbly product produced after washing with toluene and chloroform has a phosphorus content of 0.75% by weight.

b) If Example 2a is repeated but instead of l-methyl-1-phospha-3-cyclopentene-1-oxide, 1-methyl-1-phospha-2-cyclo-pentene-l-oxide is used then the phosphorus content of the reaction product is 0.2% by weight.

14 parts by weight of the unsaturated polyester of Example 2 are mixed with 6 parts by weight 1-allyl-1-phospha-2-and 3-cyclopentene-1-oxide and 0.3 parts by weight benzoyl peroxide and slowly heated under agitation to 150C. A
crumbly product is produced which, after extraction with toluene and chloroform, has a phosphorus content of 2.7% by weight.

On heating 5 parts by weight of the catalysts with 150 parts by weight of a mixture of 2,4- and 2,6- toluylene-diisocyanate (80:20) to 90C, 3 liters carbon dioxide are generated under carbodiimidization within one hour.

9.8 parts by weight maleic acid anhydride and 5.2 parts by weight diethylene glycol are heated under nitrogen to 175C with 25.6 parts by weight of a diester of an isomer mixture of l-methyl-2- or -3-phosphonic acid phospholane oxide and polypropylene glycol (molecular weight 511) and the water produced during the esterification reaction is distilled off. The gel-like product is mixed with 0.6 parts by weight benzoyl peroxide and heated to 150C. Soluble constituents are extracted from the crumbly product produced with toluene eA 16,592-Ca - 23 -424~

and chloroform.

If 1 part by wei~ht of the catalyst is heated to 110C with 34.8 parts by weight of a mixture of 2,4- and 2,6-toluylene diisocyanate (80 : 20), 2 liters of carbon dioxide are produced within 10 minutes.

9.8 parts by weight maleic acid anhydride are con-densed for 3 hours at 175C under an atmosphere of nitrogen with 9 parts by weight diethylene glycol and 3.7 parts by weight of a product obtained by heating 1 mol l-methyl phos-pholane-2 and 3-phosphonic acid-dimethylester with 2 mol di-ethanol amine. The water produced is continuously distilled off and, subsequently, the condensate is treated with toluene and chloroform, to extract residual soluble components. The product thus obtained has a phosphorus content of 0.6% by weight.

1 part by weight of this product is heated with 84 parts by weight hexamethylene diisocyanate to 190C and 2 liters of carbon dioxide are generated within 5 hours.

10 parts by weight of the product are heated with 174 parts by weight of a mixture of 2,4- and 2,6-toluylene diisocyanate to 70C. Within 30 minutes, 10 liters of carbon dioxide are developed as a result of the incipient carbodi-imidization of the isocyanate.

7.1 parts by weight of a 2% by weight solution of poly-p-iodine styrene in toluene are added dropwise at 0C
to 150 ml (0.22 mol) of an n-butyl lithium solution in toluene.

LeA 16,592-G - 24 -m~4z~l Subsequently 35.5 parts by weight 1-chloro-3-methyl-1-phospha-2 and 3-cyclopentene-1-oxide are added rapidly at 20C. After 1 hour of agitation, the reaction mixture is mixed with 5 ml water concentrated, digested with a little water and then dried in a desiccator using phosphorus pentoxide.

Toluylene diisocyanate can be carbodiimidized at 60C by means of the highly effective catalysts produced.

15 parts by weight poly-p-iodine styrene, cross-linked with 2~ divinyl benzene, are soaked in 100 ml toluene and200 ml of a 1.5 normal solution of n-butyl lithium are added dropwise in n-hexane. The metallized solid product is removed by suction under nitrogen and reacted at room temperature with 9.7 parts by weight 3-chloro-1-methyl-1-phospha-2 and 3-cyclopentene-1-oxide, produced from chloroprene and dichloro-methyl phosphine. The product is filtered and treated with toluene and chloroform.

Using the catalyst, toluylene diisocyanate can be carbodiimidized at 100C.

50 parts by weight polystyrene are mixed with 268 parts by weight phosphorus trichloride and the mixture is reacted for 5 days at 200C (see also U. S. Patent No. 2,844, 546). The excess phosphorus trichloride is then distilled off, the residue is absorbed 3 times with perchloroethylene and, in each case, the solvent is distilled off.

LeA 16,592-G - 25 -1~94Z41 190 parts by weight isoprene and 0.6 parts by weight ionol are added to the solid product thus purified under nitrogen and the mixture is left to stand for 10 days at room temperature. The solid product is washed with per-chloroethylene, hydrolyzed in 1 liter ice water, removed by suction and dried using phosphorus pentoxide.

34.8 parts by weight of an isomer mixture of 2,4-and 2,6-toluylene diisocyanate (80 : 20) are carbodiimidized using 3 parts by weight of the catalyst at 140C. 1 liter of carbon dioxide is produced within 1 hour.

A mixture of 3 parts by weight polystyrene, 6 parts by weight styrene, 1 part by weight l-allyl-phospholinoxide (l-allyl-l-phospha-2 and 3-cyclopentene l-oxide)[produced from equivalent parts of l-chloro-phospholinoxide (l-chloro-l-phospha-2 and 3-cyclo-pentene-1 - oxide) and allylmagnesium iodide in tetra-hydrofuran]
0.6 parts by weight divinyl benzene and 0.008 parts by weight dibenzoylperoxide is poured into a cylinder tube under nitrogen. After 30 days at 32C
the solid product is scraped and released of residual soluble constituents with toluene and chloroform. The phosphorus content of the product is 0.3% by weight.

Under the effect of the catalyst, toluylene diisocyanate converts into the carbodiimide at 75C.

LeA 16,592-~ - 26 -., 10~4Z4~

9 parts by weight styrene and 0.1 parts by weight divinyl benzene are mixed with 1 part by weight l-methyl-l-phospha-2 and 3-cyclopentene-1-oxide and polymerized with 0.3 parts by weight benzoyl peroxide as the initiator at 110C.
After washing with toluene and chloroform, the product has a phosphorus content of 1~ by weight.

6.8 parts by weight 1-chloro-1-phospha-2 and 3-cyclopentene dissolved in 20 parts by weight dichlorobenzene are added to 2 parts by weight of a polyvinyl alcohol (molecular weight approximately 15000) at room temperature (U.S. Patent No. 3,723,520), 4 parts by weight pyridine are added dropwise, 0.1 parts by weight ethyl iodide are added and the mixture is heated to 110C. The solid product produced is removed by suction, washed with water and then with ether and dried by means of phosphorus pentoxide.

The product is a good carbodiimidization catalyst for 2,4- and 2,6-toluylene diisocyanate at a temperature of 150C. 3 liters of carbon dioxide are evolved at 170C from 70 parts by weight of a mixture of 2,4- and 2,6- toluylene diisocyanate (80 : 20) and 2 parts by weight of catalyst within 10 minutes.

160 grams malonic acid diethyl ester are heated under reflux with 106 grams diethylene glycol and 1 ml 10% sulphuric acid in 100 ml toluene for 24 hours and, subsequently, the toluene is slowly distilled off. 240 g of this product are mixed with 240 g of an unsaturated polyester of equivalent quantities of maleic acid anhydride and diethylene glycol LeA 16,592-G - 27 -(acid number 8), 206 g 1-methyl-1-phospha-2 and 3-cyclopentene -l-oxide and 10 g benzoyl peroxide are added and heated to 150C.
The crumbly product produced, after extraction with toluene and chloroform, has a phosphorus content of 1~.

If 1 g of the catalyst is heated to 85C with 34.8 g of a mixture of 2,4- and 2,6-toluylene diisocyanate (80 : 20), 4 liters of carbon dioxide are evolved within 3 hours.

350 g of an unsaturated polyester having an acid number 9, (produced from equivalent quantities of maleic acid anhydride and tetraethylene glycol) are mixed with 150 g l-methyl-2 and 3-allyloxy-1-phospha-cyclopentene-1-oxide, subsequently heated slowly to 150C with 7.5 g benzoyl peroxide under agitation and then agitated for 1/2 hour. The crumbly product produced is extracted with toluene and with chloroform.

133 g o-tolyl isocyanate are heated with 5 g of a solid insoluble catalyst according to Example la under agitation to 180C. After the evolution within 1.5 hours of 12.3 liters of carbon dioxide, the catalyst is removed by suction and the filtrate distilled. 95.3 g di-o-tolyl-carbodi-imide of Kp. 135 - 137C/0.1 Torr (87% of theoretical yield) are produced.

133 g o-tolylisocyanate are heated under agitation to 140C with 5 g of a solid insoluble catalyst according to Example 2a. After the evolution within 2 hours of 12.1 liters LeA 16,592-G - 28 -~.~94Z41 carbon dioxide, the catalyst is removed by suction and the filtrate distilled. 103.5 g di-o-tolylcarbodiimide of Kp 130 to 132C/0.1 Torr (94% of theoretical yield) are obtained.

203 g 2,6-diisopropyl-phenylisocyanate are heated under agitation to 200C with 5 g of a catalyst according to Example la. After the evolution within 12 hours of 8.9 liters carbon dioxide, the catalyst is removed by suction and the filtrate (177 g) distil]ed. 132 g bis-(2,6-diisopropyl-phenyl)-carbodiimide of Kp 165 - 168C/0.1 Torr (71% of theoretical yield) are obtained.

1500 g of a mixture of 2,4- and 2,6 -toluylene diisocyanate (80/20) are heated to 100C with 50 g of catalyst according to Example 2a. After the evolution of 38 liters carbon dioxide the product is filtered. It has a viscosity n 24 = 14 cP and an isocyanate content of 39%.

300 g diphenyl methane-4,4'-diisocyanate are heated at 80 to 100C with a catalyst according to Example la.
After 3 liters carbon dioxide have been developed, a product which is liquid at room temperature is obtained, having an isocyanate content of 29% and a viscosity n24 = 46 cP.

168 g 1,6-hexamethylenediisocyanate are heated to 150C with 5 g of a catalyst according to Example la. After the formation of 14 liters carbon dioxide, the product is LeA 16,592-G - 29 -~O9~Z4~

filtered and formed into thin layers. Then it has a viscosity ~24 = 580 cP and an isocyanate content of 23%.

When applied to a glass plate, the product forms a scratch - resistant elastic film as a result of the reaction with atmospheric molsture.

A mixture of 111 parts by weight l-isocyanato-3,3,5-trimethyl~5-isocyanatomethyl-cyclohexane and 84 parts by weight l,6-hexamethylene diisocyanate is heated to 160C and mixed with 5 g of a catalyst according to Example la. After the development of 7.3 liters carbon dioxide, the product (viscosity n24 = 170 cP) is filtered and formed into thin layers at 80C/0.12 Torr, with monomeric isocyanate being drawn off. The product formed into thin layers has, in addition to carbodiimides a high content of isocyanato-~retoneimines. (n24 = 916 cP; isocyanate content = 23.9).

S00 g (2 mol) diphenylmethane-4,4'-diisocyanate are heated to 140C with 20 g of the catalyst of Example la.
After 20 liters carbon dioxide have been released, the isocyanatocarbodiimide containing uretone imine groups is released from the catalyst by filtration.

The product is stirred in proportions of 10, 30 and 50~ (a; b; c;) into molten diphenylmethane-4,4'-diisocyanate, producing storage stable products which are liquid at room temperature.

a) isocyanate content = 31 % n 24 = 22 cP

LeA 16,592-G - 30 -109~Z4~1 b) isocyanate content = 28% n 24 = 140 cP
c) isocyanate content = 25.2% ~24 = 1300 cP

LeA 16,592-G - 31 -

Claims (10)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:-

1. High molecular weight carbodiimidization catalysts which are insoluble in organic isocyanates and which comprise a high molecular weight, insoluble, organic matrix and a low molecular weight carbodiimidization catalyst bound to the matrix via covalent bonds.

2. The carbodiimidization catalyst of Claim 1 wherein said matrix is bound to a catalytically active group selected from the group consisting of (I) , (II) ,and , wherein R1 is selected from the group consisting of the organic matrix and alkyl, aryl and aralkyl radicals with 1 to 14 carbon atoms, and R2, R3, R4, R5 represents hydrogen, halogen, C1 - C14 alkyl, aryl or aralkyl radicals, alkoxycarbonyl, phosphonic acid ester - or C1- C4 oxyalkyl radicals or mercapto alkyl LeA 16,592-G

radicals or HO-.

3. The carbodiimidization catalyst of Claim 2, wherein said matrix is a polyester resin and wherein said catalytically active groups are bound thereto via at least one of the radicals R1 to R5 by an ester group, an ether group, or a C-C bond or the phospholane ring is bound directly to the matrix via C-C
bonds.

4. The carbodiimidization catalyst of Claim 2, wherein said matrix is a polystyrene resin and wherein said catalytically active groups are bound to the matrix via at least one of the radicals R1 to R5 by an ether group, a C-C-bond or the phospho-lane ring is bound directly to the matrix via a C-C-bond.

5. The carbodiimidization catalyst of Claim 4 wherein said polystyrene resin is cross-linked with divinyl benzene.

6. The carbodiimidization catalyst of Claim 2, wherein said matrix is a polyvinyl alcohol and wherein R1 represents the polyvinyl alcohol matrix.

7. The carbodiimidization catalyst of Claim 2 wherein said organic matrix has a molecular weight of at least 2000.

8. The carbodiimidization catalyst of Claim 7 con-taining from 0.05 to 23 percent by weight of phosphorus.

9. The carbodiimidization catalyst of Claim 8 contain-ing from 0.3 to 8 percent by weight of phosphorus.

10. A process for the production of high molecular LeA 16,592-Ca weight carbodiimidization catalysts comprising reacting a high molecular weight organic matrix having functional groups or suitable monomers for the preparation thereof with low mole-cular weight carbodiimidization catalysts or the precursors thereof, which low molecular weight catalysts or precursor which contain groups reactive with the functional groups of the matrix or the monomers.

LeA 16,592