US3546008A - Sizing compositions and fibrous articles sized therewith - Google Patents

Description

United States Patent l US. Cl. 117138.8 21 Claims ABSTRACT OF THE DISCLOSURE Fibrous articles (such as textile yarn, hemp rope, and tire cord) are sized with sizing compositions comprising linear, water-dissipatable polyesters derived from at least one dicarboxylic acid component, at least one diol component, at least mole percent of said diol component being a poly(ethylene glycol), and a difunctional monomer containing a --SO M group attached to an aromatic nucleus, wherein M is hydrogen or a metal ion.

This invention relates to sizing compositions and to fibrous articles sized therewith. In one of its more specific aspects, this invention relates to sizing compositions for textile yarns made from linear polyesters.

When textile materials are to be used in the form of multifilament yarns for the fabrication of textile materials, it is desirable before the weaving process to treat the warp yarn with a sizing composition (sometimes referred to as an agent) which adheres to and binds the several filaments together. This treatment strengthens the several filaments and renders them more resistant to abrasion during the subsequent weaving operations. It is especially important that the sizing composition impart abrasion resistance to the yarns during weaving because abrasion tends to sever the yarn and to produce end breaks which, of course, lower the quality of the final woven product. It is also important that the sizing composition be one which can be subsequently removed from the yarns by scouring.

Various high molecular weight materials have been suggested as sizes for yarns. Among such materials are gelatin, sodium polyacrylate, polyvinyl alcohol, and the sodium salt of a 50/50 maleic anhydride-styrene copolymer. However, some of these materials are not readily compatible with or do not adhere well to textile yarns and thus do not form a protective coating or film thereon. Other materials coat the yarn but do not impart more than a slight degree of abrasion resistance. Therefore, a I

need exists for sizing compositions which avoid the abovementioned disadvantages.

It is an object of this invention to provide sizing compositions, fibrous articles sized therewith, and processes for sizing said fibrous articles. Another object of this invention is to provide sizing compositions for textile yarns, especially those yarns made from linear polyesters. Still another object of this invention is to provide sizing compositions which will adhere to and bind together the several filaments of textile yarns. Still another object of this invention is toprovide sizing compositions which will impart abrasion resistance to textile yarns during weaving. Yet another object of this invention is to provide sizing compositions which can be removed from textile yarns by scouring. Other objects of this invention will appear herein.

These and other objects are attained through the practice of this invention, one embodiment of which comprises providing a fibrous article sized with a sizing composition comprising a linear, water-dissipatable polyester derived essentially from components (A) at least one di- 3,546,008 Patented Dec. 8, 1970 carboxylic acid, (B) at least one diol, at least 20 mole percent of said diol component being a poly(ethylene glycol) having the formula ntocn cn anon wherein n is an integer of from two to about ten, and (C) a difunctional monomer containing a SO M group attached to an aromatic nucleus, wherein M is hydrogen or a metal ion.

Another embodiment of this invention through which the above objects are attained comprises providing a process for sizing a fibrous article, wherein said process comprises applying to said fibrous article a sizing composition as described above.

The term dissipatable will be understood to refer to the action of Water or an aqueous solution (preferably at least 25 percent by weight of water) on the polyester sizing composition. This term is specifically intended to cover those situations wherein the polyester sizing composition is dissolved or dispersed in water or an aqueous solution.

We have discovered that the above-described noncrystalline polyesters are effective, when dissipated in water or aqueous solutions, as sizes for a variety of natural and synthetic textile yarns. Examples of such yarns include those made from polyesters, such as poly(ethylene terephthalate) and poly(l,4-cyclohexylenedimethylene terephthalate), cotton, rayon, cellulose acetate, nylon, and polypropylene. Therefore, although this invention will be illustrated by references to polyesters, our sizing composition may be used on these other types of textile materials with good results obtained.

The sizing compositions of this invention are particularly useful for sizing polyester yarn, which is among the most difficult of all textile yarns to size. In fact, presently no really effective sizing composition is known for continuous filament polyester fibers, and an expensive twist must be imparted to protect them during weaving. The sizing compositions of this invention make it possible to weave low or zero twist polyester fibers with substantially no defects.

It is necessary for greater effectiveness that a textile size be substantially scoured or removed from the woven fabric so that it will not interfere with subsequent finishing and dyeing operations. In practical terms, this means that the sizing composition must be water-dissipatable (that is, either water-soluble or water-dispersible). The non-crystalline polyesters that are effective as sizes in the process of this invention contain a hydrophobic moiety and a hydrophilic moiety. For example, a preferred sizing composition is prepared from isophthalic acid, the sodium salt of 5-sulfoisophthalic acid, and diethylene glycol. In this composition, the isophthalic acid is hydrophobic, the sodium sulfoisophthalic acid is hydrophilic, and the diethylene glycol is hydrophilic. This particular composition, when added to water, forms a dispersion which exhibits a dispersion viscosity higher than that of water but lower than that which might be expected if the polymer were completely dissolved. As the temperature is raised from 25 C. to about -C., no appreciable increase in dispersion or solution viscosity results. Thus, this particular composition acts as if it were partially soluble in water and partially insoluble, a behavior which is consistent with its hydrophobic-hydrophilic composition. In addition, the hydrophilic portion of the molecule can be increased and a completely water-soluble composition obtained. Conversely, the hydrophobic moiety of the polyester molecule can be increased and a composition which is water-dispersible but which imparts little or no additional viscosity to water can be used. It is desirable that the size composition, on evaporation of the water, (1)

adhere to the fiber being sized, (2) form a sufficiently protective film so that the fiber is protected during weaving, and (3) be removable from the fiber under ordinary conditions of scouring.

The efficiency of a material as a size can be determined by measuring its Duplan abrasion resistancethe higher the Duplan value, the better it protects the yarn. The Duplan Cohesion Tester is a machine designed to test the effectiveness of a size solution by testing the cohesion of the sized filament yarn before the warp reaches the loom. Samples of sized yarn under a constant tension are abraded by friction plates moving back and forth on the yarn at a constant rate. The average number of strokes per strand required to separate the filaments in ten strands of yarn are reported as the Duplan value. Forty tests on each sample are considered the standard test. In examining the strands at intervals for open places, an air jet is blown along each strand to assist in detecting openings.

The novel sizes of this invention may be used in the following manner: the size, in powder or pellet form, is added to water at any convenient temperature between somewhat below room temperature to about 100 C. and is subjected to mild agitation. Depending upon the specific properties of the particular composition being used, a clear to cloudy, moderately viscous, stable dissipation of the size in water is obtained.

The yarns to be sized are the highly polymeric, fiberand film-forming, linear polyesters derived from at least one aliphatic, cycloaliphatic, or aromatic dicarboxylic acid and at least one aliphatic, cycloaliphatic, or aromatic diol. The preparation of these polyesters and the spinning of fibers therefrom are well-known procedures and need not be detailed herein. The acids and diols described below for the sizing composition are examples of components from which these polyesters can be prepared.

The dicarboxylic acid component from which the linear, water-dissipatable polyester sizing composition is prepared can be any aliphatic, cycloaliphatic, or aromatic acid. Examples of such dicarboxylic acids include oxalic; malonic; dimethylmalonic; succinic; glutaric; adipic; trimethyladipic; pimelic; 2,2 -dimethylglutaric; azelaic; sebacic; fumaric; maleic; itaconic; 1,3-cyclopentanedicarboxylic; 1,2-cyclohexanedicarboxylic; 1,3-cyclohexanedicarboxylic; 1,4-cyclohexanedicarboxylic; phthalic; terephthalic; isophthalic; 2,5-norbornanedicarboxylic; 1,4-naphthalic; diphenic; 4,4-oxydibenzoic; diglycolic; thiodipropionic; 4,4'-sulfonyldibenzoic; and 2,5-naphthalenedicarboxylic acids. If terephthalic acid is used as the dicarboxylic acid component of the polyester, especially good results are achieved when at least five mole percent of one or the other acids listed above is used.

It should be understood that the use of the corresponding acid anhydrides, esters, and acid chlorides of these acids is included in the term dicarboxylic acid. The esters are preferred, examples of which include dimethyl 1,4-cyclohexanedicarboxylate; dimethyl 2,6-naphthalenedicarboxylate; dibutyl 4,4-sulfonyldibenzoate; dimethyl isophthalate; dimethyl terephthalate; and diphenyl terephthalate. Copolyesters may be prepared from two or more of the above dicarboxylic acids or derivatives thereof.

At least about 20 mole percent of the diol component used in preparing the polyester sizing composition is a poly(ethylene glycol) having the formula wherein n is an integer of from two to about ten. Examples of suitable poly (ethylene glycols) include diethylene, triethylene, tetraethylene, pentaethylene, hexaethylene, heptaethylene, octaethylene, nonaethylene, and decaethylene glycols, and mixtures thereof. Preferably the poly- (ethylene glycol) employed in the polyester of the present invention is diethylene glycol, triethylene glycol, or mixtures thereof. The remaining portion of the diol component is at least one aliphatic, cycloaliphatic, r aromatic diol. Examples of these diols include ethylene glycol; propylene glycol; 1,3-propanediol; 2,4-dimethyI-2-ethylhexane-1,3-diol; 2,2-dimethyl-1,3-propanediol; 2-ethyl-2- butyl-1,3-propanediol; 2-ethyl-2-isobutyl-1,3-propanediol; 1,3-butanediol; 1,4-butanediol; 1,5-pentanediol; 1,6-hexanediol; 2,2,4-trimethyl-1,6-hexanediol; 1,2-cyc1ohexanedimethanol; 1,3-cyclohexanedimethanol; 1,4-cyclohexanedimethanol; 2,2,4,4-tetramethyl-1,3-cyclobutanedio1; and p-xylylenediol. Copolymers may be prepared from two or more of the above diols.

A third component used to prepare the polyester sizing composition is a difunctional monomer containing a SO M group attached to an aromatic nucleus, wherein M is hydrogen or a metal ion. This difunctional monomer component .may be either a dicarboxylic acid (or derivative thereof) containing a SO M group or a diol containing a SO M group. The metal ion of the sulfonate salt group may be Na+, Li K+, Mg++, Ca++, Cu++, Fe, or Fe+++. It is possible to prepare the polyester using, for example, a sodium sulfonate salt and later by ion-exchange replace this ion with a different ion (for example, calcium) and thus alter the characteristics of the polyester.

The SO M group is attached to an aromatic nucleus, examples of which include benzene, naphthalene, anthracene, diphenyl, oxydiphenyl, sulfonyldiphenyl, and methylenediphenyl.

Especially good results are obtained when the difunctional monomer is the sodium salt of a sulfoisophthalic, sulfoterephthalic, sulfophthalic, or 4-sulfonaphthalene-2,7- dicarboxylic acid (or derivatives of such acids). A highly preferred such monomer is S-sodiosulfoisophthalic acid or a derivative thereof such as S-sodiosulfodimethyl isophthalate. Another preferred difunctional monomer is 5- sulfoisophthalic acid. Monomers containing a SO M group are described in Kibler et al. US. Ser. No. 695,- 339, filed Jan. 3, 1968 now abandoned in favor of a continuation-in-part.

Other effective difunctional monomers containing a SO M group attached to an aromatic nucleus include metal salts of aromatic sulfonic acids (or esters thereof). These monomers have the general formula wherein X is a trivalent aromatic hydrocarbon radical, Y is a divalent aromatic hydrocarbon radical, R is hydrogen or an alkyl group of one to four carbon atoms, M is hydrogen, Na+, Li+, K+, Mg++, Ca++, Cu, Fe, or Fe+++, and a is 1, 2, or 3. These monomers are described, including methods for their preparation, in Lappin et a1. U.S. Ser. No. 695,349, filed Jan. 3, 1968 now US. Pat. No. 3,528,947, patented on Sept. 15, 1970. Examples of preferred monomers here are 4-sodiosulfophenyl-3,S-dicarbomethoxybenzenesulfonate, 4-lithiosulfophenyl-3,5-dicarbomethoxybenzenesulfonate; and 6-sodiosulfo-2-naphthyl-3,5-dicarbomethoxybenzenesulfonate.

Other effective difunctional monomers containing a SO M group attached to an aromatic nucleus include metal salts of sulfodiphenyl ether dicarboxylic acids (or esters thereof). These monomers have the general formula ROOC s03- wherein R is hydrogen, an alkyl group of one to eight carbon atoms, or phenyl, and M is hydrogen, Na Li+, Mg++, Ca++, Cu++, Fe++, or Fe+++ and a is 1, 2, or 3. These monomers are described, including methods for their preparation, in Lappin et al. US. Ser. No. 671,565, filed Sept. 29, 1967 now abandoned and substituted by streamlined continuation Ser. No. 835,295 which was published Nov. 18, 1969 as a Defensive Publication, 868, 0.6. 730. Examples of preferred monomers here are dimethyl 5- [4-(sodiosulfo)phenoxy] isophthalate, dimethyl 5- [4- (sdiosulfo)phenoxy] terephthalate, and -[4- (sodiosulfo) phenoxy1isophthalic acid.

The above-identified applications (U.S. Ser. Nos. 695,- 339; 695,349; and 671,565) are hereby incorporated by 6 0.25 gram of polymer per 100 ml. of a solvent composed of 60 percent phenol and 40 percent tetrachloroethane.

Various additives may be incorporated into the sizing compositions to achieve specific results. Examples of such additives include talc -(to prevent the powder or pellets reference as a part of the present specification. 5 from adhering together), titanium dioxide, dyes, other pig- When the difunctional monomer containing the --SO M ments, and stabilizers. groups is an acid or derivative thereof (such as its ester), The following examples are included for a better underthe polyester should contain at least about eight mole standing of this invention. percent of the monomer based o n total ac d content, with EXAMPLE 1 more than ten mole percent giving partlcularly advantageous results. When the difunctional monomer is a diol, A InlXtuTe 0f grams molfi) Q dlmethyl the polyester should also contain at least about eight mole Phthalate, grams ((1125 mole) of by p percent of the monomer based on total diol content, with e grams mole) Q heXahYdf010Phth111 more than ten mole percent giving particularly advanta- 15 mild, grams mole) of dlmethyl5'sodlosulfolso geous results. Greater dissipatability is achieved when the Phthalate, grams mole) 0f q y q y difunctional monomer constitutes from about 12 mole perf l a Percent catalyst SOhltlQIl 0f tltal'llllm cent to about 45 mole percent of the total content of acid ISOPTOPOXIde 1S Stlfred a d heated at 200= and a or diol components of the polyester. vacuum of 0.3 mm. is applied. Heating and stirring is con- To obtain the polyester sizing compositions of this intinued for one hour under these conditions. After cooling vention, the difunctional monomer containing the $O M the Polymer f llas of 053 and 1S tough group may be added directly to the esterification reaction and y- 1S dlsslpated hot Water f The fiXteIlt mixture from which the polyester will be made. Thus, these 0f abpllt 20 Weight percent to glve p sllg y S HS ono can b d as a wmponent i th original solutlon. After storage of the solutlon for three months polyester reaction mixture. Other various processes which r00m t pe atu e, the Water is evaporated from a pormay be employed in preparing these sizing compositions The resldual} P y has an -V- Of 15 N0 are well known in the art and are illustrated in such patmeasurable hydrolysls has Occurredents as US. 2,465,319; 3,018,272; 2,901,466; and 3,075, EXAMPLE 2 952. These patents illustrate ester interchange and p0- lyrnerization processes. The following table shows the properties of a number Both the fiber-forming polyesters to be sized and the of polyester sizing compositions made from difunctional polyester sizing compositions will have an inherent vismonomers containing SO M groups. All are made by cositv (I.V.) of at least 0.3, as measured at 25 C. using the general procedure of Example 1.

TABLE Mole Mole Mole Polymer Dicarboxylic acid Percent Sulfonate Percent Diol Percent I.V. {Isophthalic 52.5 7.5 DEG 3 100 4 A Terephthalic 25 SIP 1 Hexahydroisophthalie 15 B Isophfhalit' 90 SIP 10 DEG 100 0.53 C Hexahydroterephthahcn. 90 SI]? 10 DEG 100 0. 73

Isopht ic DEG D Tmrpphfhalic 25 SIP 10 EG 0.60

Hezahydroisophthalic 15 20 Isophthalic 50 E --{Terephthalic 25 10 DEG 100 0.

Hexahydmisophthalic" 15 sopllillgh 1:0 10 DEG 100 0.48 G --{ri:3ah 3tg;@g,rtsnm 30 i DEG 100 H Isophthalic 10 DEG 0. 42 I Terephthalie 92 SIP 8 TEG 7 100 0.33 J Isophthalic 92 SIP 8 TEG 100 0. 59 K -410 90 SIP 10 {g E g B 0. 45 L Adipic 90 SIP 10 100 0.69

- 50 M lsophthahc 90 SIP 10 5O 0. 48 N do 90 SIP 10 {ggg 0. 51 0 do s0 SIP 20 {g gg 0.32 P- dn s0 SIP 20 {g gg 0.38

1 SIP-5-sodiosulfoisophthalic acid. 2 DEG-diethylene glycol. 3 E G-ethylene glycol.

4-sodiosulfophenyl-3,S-dicarboxybenzene sulionate,

HO O O HOOC/ 5 5-[4-(sodiosulfo)phenoxy1isophtha1lc acid, 0 O 0 H 5 2(2-sodiosu1iophenyl)Q-ethylmalonic acid, (I) O O H COOH S OaNB 7 TEGtriethy1ene glycol.

B OHDM-1,4-cyclohexanedimethanol.

7 EXAMPLE 3 A mixture of 15 parts of the polyester sizing composition (I.V. of 0.5) derived from 90 mole percent isophthalic acid, 10 mole percent S-sodiosulfoisophthalic acid, and diethylene glycol and 85 parts of water gives a dispersion that is slightly hazy in appearance and that has a Brookfield viscosity of 15. A poly(ethylene terephthalate) yarn containing 40 filaments is passed through the aqueous dispersion of the sizing composition and dried. A 4.5 percent pickup of the size results. Pickup is a measurement of the weight percent of the size relative to the weight of the sized yarn. The Duplan abrasion resistance of the sized yarn is 275, showing that this polyester is an excellent size for polyester yarn.

EXAMPLE 4 The conditions of Example 1 are repeated except that 7.5 parts of the polyester sizing composition are suspended in 92.5 parts of water. A 2.7 percent pickup of size results. The Duplan abrasion resistance of this sized yarn is 244, indicating that this polyester is an excellent size for polyester yarns even at low pickup.

EXAMPLE 5 The conditions of Example 1 are repeated except that 12.5 parts of gelatin are dissolved in 87.5 parts of water. The size pickup is not determined, but the supposedly sized polyester yarn has a Duplan abrasion resistance of only 13. This shows that gelatin is not a satisfactory size for polyester fibers.

EXAMPLE 6 The conditions of Example 1 are repeated except that 7.5 parts of the sodium salt of a 50/50 maleic anhydridestyrene copolymer are dissolved in 92.5 parts of water. Size pickup is not determined. The supposedly sized polyester yarn has a Duplan abrasion resistance of only 8. This shows that this copolymer is not a satisfactory size for polyester fibers.

It will be noted that in the preceding examples, size/ water ratios (weight/weight) of 15/85 and of 7.5/92.5 are used. However, the size/water ratio may vary from 1/99 to 50/50.

When the size is a relatively hydrophobic, it does not impart much viscosity to the aqueous size composition, and very high solids size compositions can be prepared. In addition, in the case of relatively hydrophobic polyester sizes, very high molecular weight products-can be used without the formation of a size composition that is too viscous to use. This can be a real advantage when it is desirable to use, for example, a high I.V. size material for high toughness. The extent to which the yarn being sized pick up size will be affected by the solution or suspension viscosity of the size composition, with more viscous compositions in general leading to higher pickups." It is within the scope of this invention to add various thickening agents and the like to the size composition to increase its viscosity.

Other polyester yarns and other polyester sizing compositions (such as those from the table) can be substituted in the procedure of Example 1 and good results obtained.

Although described above with particular reference to textile yarns, this invention encompasses fibrous articles in general, other examples of which are tire cord (such as rayon, nylon, or polyester tire cord) and hemp rope. In sizing these other fibrous articles, this invention does not necessarily require the removal of the sizing composition.

The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described hereinabove and as defined in the appended claims.

We claim:

1. A fibrous article sized with a sizing composition comprising a linear, water-dissipatable polyester derived essentially from components (A) at least one dicar-boxylic acid,

(B) at least one diol, at least 20 mole percent of said diol component being a poly(ethylene glycol) having the formula HtOCH CH -hDH wherein n is an integer of from two to about ten, and

(C) at least one difunctional dicarboxylic acid sulfomonomer containing a SO M group attached to an aromatic nucleus, wherein M is hydrogen or Na+, Li+, K Mg++, Ca++, Cu++, Fe++, Fe+++, or a combination thereof, said sulfo-monomer component constituting at least about 8 mole percent to about 45 mole percent of the sum of the moles of said components (A) and (C).

2. A fibrous article as defined by claim 1 wherein said component (A) is isophthalic acid.

3. A fibrous article as defined by claim 1 wherein said component (A) is terephthalic acid.

4. A fibrous article as defined by claim 1 wherein said component (A) is adipic acid.

5. A fibrous article as defined by claim 1 wherein said component (A) is hexahydroterephthalic acid.

6. A fibrous article as defined by claim 1 wherein said component (A) is a mixture of isophthalic, terephthalic, and hexahydroisophthalic acids.

7. A fibrous article as defined by claim 1 wherein said component (B) is diethylene glycol.

8. A fibrous article as defined by claim 1 wherein said component (B) is triethylene glycol.

9. A fibrous article as defined by claim 1 wherein said component (B) is a mixture of mole percent diethylene glycol and 20 mole percent ethylene glycol.

10. A fibrous article as defined by claim 1 wherein said component (B) is a mixture of 70 mole percent diethylene glycol and 30 mole percent 1,4-cyclohexanedimethanol.

11. A fibrous article as defined by claim 1 wherein said component (C) is 5-sodiosulfoisophthalic acid.

12. A fibrous article as defined by claim 1 wherein said component (C) is 4-sodiosulfophenyl-3,S-dicarboxybenzene sulfonate.

13. A fibrous article as defined by claim 1 wherein said component (C) is 5-[4-(sodiosulfo)phenoxy]isophthalic acid.

14. A fibrous article as defined by claim 1 wherein said component (C) is 2(2'-sodiosulfophenyl)-2-ethylmalonic acid.

15. A fibrous article as defined by claim 1 wherein said fibrous article is a textile yarn.

16. A fibrous article as defined by claim 15 wherein said textile yarn is made from a polyester.

17. A textile yarn as defined by claim 16 wherein said polyester is poly(ethylene terephthalate).

18. A textile yarn as defined by claim 16 wherein said polyester is poly(l,4-cyclohexylenedimethylene terephthalate).

19. A fibrous article as defined by claim 1 wherein said water-dissipatable polyester has an inherent viscosity of at least about 0.3, as measured at 25 C. at a concentration of about 0.25 gram of said polyester per ml. of a solvent composed of 60 percent phenol and 40 percent tetrachloroethane.

20. A fibrous article as defined by claim 19 wherein said sulfo-monomer component constitutes at least about 12 mole percent of the sum of the moles of said component and 21. A fibrous article sized with a sizing composition comprising a linear, water-dissipatable polyester or polyesteramide derived from at least two difunctional monomer components which are dicarboxylic acid, hy-

droxycarboxylic acid having one aliphatic hydroxy group, aminocarboxylic acid, amino-alcohol having one aliphatic hydroxy group, a glycol having two aliphatic hydroxy groups, and an organic diarnine including combinations thereof wherein the overall total moles of said monomer components comprises at least 10 mole percent of at least one or a mixture of poly(ethylene glycols) containing from 2 to 10 ethyleneoxy groups and at least 4 mole percent of at least one or a mixture of difunctional sulfomonomer components containing at least one SO M group attached to an aromatic nucleus, said nucleus being present in at least one of the aforesaid monomer components wherein M is hydrogen or Na+, Li+, K+, Mg++, Ca++, Cu++, Fe++, Fe+++, or a combination thereof, said polyester or polyesterarnide having an inherent vis- 10 cosity of at least about 0.1 measured as defined in this specification.

References Cited ALLAN LIEBERMAN, Primary Examiner L. T. JACOBS, Assistant Examiner US. Cl. X.R.