AU606706B2 - Process for protecting articles from attack by bleaching solutions - Google Patents

Description

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1/00/0il b AUITRl1$ PATENTS ACT 1952-1973 COMPLETE SPECIFICATION

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FORl OFFICE USE Form Class: lilt. CI: compos: oxiclat polyme: solutil Application NUrnber: Lodgead: Thsdouent contains the arIC1nidtents mnade under c'jctiOn 49 and is Corctfor Plin Ling.

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Name of Applicant: TO BE COMPLETED BY APPLICANT DU PONT CANADA, INC., a corporation of Canada, of Box 2200, Streetsville, Mississauga, Ontario, CANADA L5M 2H3 025 11, to baths effect Patent 15 Decemb substi of big discol mangan biguan of the biguan peroxi 25 (the t of pur Abs tre guanic camp olF catal pa ly u in cui 69 185 Address of Applicant: Actual Inventor: How,,ard Chung HO NG and Henk John KRAKE Address for Service: Care of JAMES M. LAWRIE CO., Patent Attorneys of 72 Willsmere Road, Kew, 3101, Victoria, Australia.

Complete Specific ation for the invention entitled: PROCESS FOR PROTECTING ARTICLES FROM ATTACK BY BLEACHING SOLUTIONS 'The following statement is a full desc~ription of this invention, including the best method of performing It known to me:-* Note: The description is to be typed in dotible spacing, pica type face, in an area not exceeding 250 mm In depth and 160 mm In width, on tough white paper of good quatity and it is to be Inserted Inside this form.

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14 Example 7 in phy., showed additiL A finish free 1880 dtex LYCRA spandex fibre 14- PROCESS FOR PROTECTING ARTICLES FROM ATTACK BY BLEACHING SOLUTIONS BACKGROUND OF THE INVENTION

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*10411 C 9 t a a 9 C C C C C e cc C C t e rcc It C C C II C The present invention relates to the use of compositions for the inhibition or prevention of oxidative degradation of articles formed from polymers in peroxide and hypochlorite bleaching solutions.

It is known from German Patentschrift 1 025 376 of Dithmar et al., granted on 1960 August 11, to incorporate N-phenylbiguanide into bleaching baths in order to protect polyamides against the effects of peroxide in bleaching baths. In U.S.

Patent 3 628 906 of Dithmar et al., granted on 1971 December 21, it is disclosed that alkyl or cycloalkyl substituent groups on the first and fifth positions of biguanides reduce the tendency towards discolouration in the fibre when exposed to iron and manganese compounds in bleaching baths, compared to biguanides having aryl substituent groups. In both of the above-mentioned patent specifications, the biguanide material is employed in solution in a peroxide bleaching bath.

The use of guanide or guanidine materials (the two terms are used interchangeably) for a number of purposes is known. For example, in Chemical Abstracts Vol. 100(2), 15374g, a water-insoluble guanidine derivative is described in a paper coating composition over a barrier layer to improve storage stability. Guanidines have also been used as catalysts to reduce the curing time of polyureas (Chem. Absts., Vol. 96(20), 164305m), and in curing epoxy resins (Chem. Absts., Vol. 87(10), 69185c).

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2 The coating of fibres in general is also known in the art. Both dipping and spraying methods, among others, have been used. Many patent specifications disclose sizing compositions for coating on the surface of glass fibres, used to improve the adhesion of the glass to polymer matrixes. In U.S. Patent 4 263 082 to Temple, granted 1981 April 21, a sizing composition is disclosed that comprises a lubricant, a coupling agent, a stabilizer, a non-crosslinkable film-former, a softener, a surfactant and an aqueous carrier, which improves the adhesion of glass fibres to a polyolefin material. The stabilizer may act as a secondary coupler and assist in crosslinking of the coupling agent. In Chemical Abstracts, Vol. 103'10), 72549d, a wet-degradable fibre is disclosed, the 0 0 15 0 fibre having a ethylene-vinyl acetate copolymer 0 coating of low permeability.

.00 0 In U.S. Patent 3 687 721 to Dardoufas, granted 1972 August 29, a lubricating protective film is disclosed which is applied to a multifilament polyester or polyamide yarn, and which gives the fibres greater elongation at break and greater resistance to aging. The liquid coating composition Ii comprises a glycerol oleate, ethoxylated tall oil fatty acids, sulphated glycerol trioleate or 25 25' ethoxylated alkylamine, and hexadecyl stearate.

U.S. Patent 4 325 857 to Champaneria et al., granted 1982 April 20, discloses an antisoiling coating for textile filaments comprising an aqueous dispersion of a perfluoroalkylester of a citric acid Surethane and a fluorinated alcohol, the reaction product of an epoxy resin and a carboxyl-functior.al vinyl polymer and an aqueous solution of a tertiary amine. The treated filaments are heated to dry and cure the resins on the surface of the filaments.

DC-2092 2 S3 Although the art has disclosed both protective coatings for fibres and other materials, and agents used in bleach baths to protect condensation polymer fibres from attack by peroxide, ther- remains a need for a method of protecting articles at the manufacturing stage in order to provide a product to be used in oxidative bleach environments that does not require the user to incorporate protective agents into the bleach baths.

A method of protecting articles formed from polymers by coating the articles with a composition capable of protecting the articles from oxidative bleach environments has now been found.

SUMMARY OF THE INVENTION o 0 a process for protecting an article made frm a 0 00a 0oo o polymer against degradation throug posure to 00 Sooo aqueous solutions containin eroxygen radicals, 000oo. hypochlorite radical r mixtures thereof. The S0 2process compr s coating the article with a compostlon capable of protecting the polymer against 0 egra i-i nn .00n 0 00 o°o 0 In another one of its aspects, the invention provides a process for protecting an article made a 00 0 o 25 0o 5 from polymer against oxidative degradation through exposure to aqueous solutions containing peroxygen groups, hypochlorite groups or mixtures thereof, 0000 o0 0 comprising: coating said article with a composition comprising a reactive guanide compound, and curing the article coated with said composition, i, DC-2092 3- 1 -4wherein the guanid compond is of Lthe formula: Si R1-1H- n-R2 where n is from 2 to 10, RI has from 6 to about carbons and is either an alkyl, a cycloalkyl, a monocyclic aryl or an alkyl substituted monocyclic aryl and R2 has not more than about 15 carbons and is either hydrogen, an alkyl, a cycloalkyl, an alkysubstituted monocyclic aryl or a mono-cyclic aryl.

In a preferred embodiment of the process, the curing step comprises the application of heat to the articles, advantageously at a temperature of to 120°C, preferably 80 to 120 0 C, for 2 to ooo.o minutes, and is followed by a step of cooling the °o 15 o 0 articles.

o o S o The invention also provides articles 0o a protected against oxidative degradation through 0o o oo exposure to aqueous solutions containing peroxygen Oco 0 groups, hypochlorite groups or mixtures thereof, said articles being coated with a reactive guanide 000 comhound having the above-noted formula cured on said OoO °o coate-l articles.

0 OQ 0 o T-he invntio f ur r provides a sompos c-- Sfor protecting articles made from polymers against o 9 25 ooo0 oxidative degradation through exposure to aqueous solutions containing perp.xygen groups, hypochlorite 0 groups or mixtures- hereof, comprising a reactive oo 0 guanide-eomcpound having the above-noted formula cured DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferably, the polymers are spandex polymers or are condensation polymers formed from monomers selected from the group consisting of DC-2092 4

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b 5 dicarboxylic acids, diamines, aminoacids and diols, said monomers being aliphatic or monocyclic aromatic.

In another preferred embodiment of the process, the articles may be fibres, monofilament and blown or sheet-extruded film.

Any composition which is capable of being coated onto a polymer and which is capable of protecting the polymer from oxidative bleach baths may be used. Preferably, the composition is polymerizable on the surface of the polymer upon curing. Compositions containing guanide compounds are preferred.

Guanide compounds suitable for use in the invention have the formula:

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0 0 15 II 0oo R1-NH-(-C-NH-)n-R2 o oo 0 00 O 0 0 0 o oo where n is from 2 to 10, RI has from 6 to about 00 oo 0 0o6 carbons and is either an alkyl, a cycloalkyl, a o monocyclic aryl or an alkyl substituted monocyclic o Saryl and R2 has not more than about 15 carbons and S, is either hydrogen, an alkyl, a cycloalkyl, a monocyclic aryl, or an alkyl-substituted monocyclic aryl. The number of repeating units, expressed by in the formula, and the size of the end group O c substituents is selected using the solubility and the necessary reactivity of the guanide compound. Thus oa guanides particularly useful in the process include oo biguanidines having phenyl groups substituted on the nitrogen atoms at the first and fifth positions.

SEspecially preferred guanides having 2 repeating units and an aryl or alkyl substituted aryl group are 1-(2-tolyl)-biguanide, in which R2 is H and R1 is 2-tolyl; 1-phenylbiguanide, in which R2 is H and Ri is phenyl; 1,5-diphenylbiguanide, in DC-2092 5 which Ri and R2 are phenyl; and salts thereof.

Preferred guanides having 2 repeating units and an alkyl or cycloalkyl group are l-(N-hexyl)-biguanide, in which R1, is N-hexyl and R2 is H; 1,5 (N-hexyl) biguanide, in which Rl, is N-hexyl and R2 is N-hexyl; l-(cyclohexyl) biguanide in which Rl is cyclohexyl and R2 is H; and 1,5 (cyclohexyl) biguanide in which R1 and R2 are both cyclohexyl.

The coating composition may be a sizing composition which may include conventional sizing 1 components, for example if the articles are fibres, the coating composition may contain lubricants, surfactants, antistats, emulsifiers and dispersing agents. Advantageously, the coating composition sooooo containing the guanide is applied by spraying or S 15 0o dipping methods known in the art. Spraying is O o 0o especially preferred as it is readily adaptable to 0 0 o0. o existing equipment used for extrusion or spinning.

00 o 0oo For spray application the composition containing the ooo, guanide may be prepared by dissolving the guanide compound. The guanide compounds having 2 repeating units, i.e. n=2, tend to be soluble in warm water and 0 oa 00 0 o in the lower alcohols and ketones; as the number of 0 repeating units increases up to about 10, and as the length of the end-group substituents increases, the solubility decreases so that lower concentrations of guanide or stronger solvents are used. Conveniently, if the guanide has 2 to about 4 repeating units, it may be dissolved in water, preferably hot water, in a ratio of 1:20 to 1:50 by weight. Other ingredients as desired may be incorporated into the composition either in slurry or solution form, and the resulting solution or slurry may be sprayed onto the article downstream from the extrusion or spinning head after the point at which the polymer has solidified. A' suitable coating may be obtained when the amount of guanide applied to the article is from 0.1 to .percent, preferably from 0.2 to 1.0 percent, by weight.

DC-2092 6 The guanide may be cured on the articlo by exposure to a temperature of about 50 to 120 0

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preferably 80 to 120'C, most preferably 100 to 120 0 C,for a period of about 2 to 30 minutes, preferably from about 3 to 10 minutes. As described in more detail hereinafter, the curing reaction Sappears to be a condensation both between the reactive groups on the polymer and the biguanide and within the biguanide itself involving evolution of ammonia, and consequently no oxygen need be present during curing. The cured coated article may then be cooled to an appropriate temperature readily selectable by the person skilled in the art.

S o.oo. Finally, the article may be prepared for shipment; 0 0 0oo for example if the article is a fibre, the fibre may o o° 5be wound onto a suitable package.

o° 15 00 0 Articles that may be treated by the process 0 oo. include fibres, monofilament, blown and extruded .oooo. film, moulded articles and extruded shapes.

Especially preferred are articles having a high surface-to-volume ratio, for example fibres, ooo00 20 monofilament and blown and extruded film, which tend O 00 to be more affected by bleaching treatment than articles of a low surface-to-volume ratio.

I t I t The present invention is illustrated by the following examples.

I I C o l Example 1 In a spinning run, a hexamethylene diamine-adipic acid polymer having a relative viscosity of 51 (in 90 wt.% formic acid) was melt-spun into filaments having a mass of 15 denier (17 dtex). A 2.5 aqueous solution of a guanide having the parameters n=2, R1 being 2-tolyl and DC-2092 7 £7 R2 being hydrogen, which is I.-(2-tolyl)-biguanide (Proventine 7, Henkel Chemicals (Canada) Ltd., Montreal, Quebec) was prepared at 68'C and sprayed onto the fibre, the fibre being at about 401C, through pre-warmed transfer lines and conventional spraynozzles. The fibre was heated in a conventional drier at a temperature of 110'C with a residence time of 3 minutes. The moisture content of the coated polymer in staple form was 21.99 before the heating step and 2.45 after the heating step, compared to 4.19 before the heating step and 2.31 after, respectively, for an uncoated control sample produced under the same conditions. The moisture content in 0. the bale was 5.73 and 3.77 respectively for 0 0 000 0 coated and uncoated fibre. The level of biguanide o 0000coating on the fibre was measured by trichloroethane 00a 0 extraction, both before and after heating, and was 00 determined to be 0.2 by weight prior to the heating 000 0 step, indicating a high degree of curing onto the polyamide fibre under the coating conditions. The Q0 00 20 coating was unextractable after the heating step, suggesting that the curing was complete thereafter.

0 00 000 0 Both coated and control samples of fibre were bleached in either 1.5 wt.% hydrogen peroxide 0 00t 000 solution at pH 4 at 90'C for 120 minutes and in 1.5 wt.% sodium hypochlorite bleach solution at pH at 90 0 C for 120 minutes. Table 1 illustrates the 0 00a 00 performance of the coated and uncoated fibres compared to that of uncoated fibres treated in a similar bleaching bath according to the prior art processt In peroxide bleach and especially in hypochlorite bleach, the fibres zoated according to the invention retain more of their original properties than untreated fibres or fibres bleached in the presence of the biguanide in the bleach solution according to the prior art.

DC-2092 8 Table I- Percentage Change in Fibre Properties After Bleaching Spray Untreated Biguanide Property Coated Fibre in Bleach ivHdrogen Peroxido Bleach Breaking Strength -11.9 -37.4 -23.7 Elongation at Break -30.6 -50.2 -27.3 Tenacity -11.5 -39.7 -22.3 Sodium Hypochlorite Bleach Breaking Strength -29.7 -33.9 -42.4 Elongation at Break -36.9 -44.8 -40.3 Tenacity -30,0 -32.2 -41.0 Example 2 a* a t o 15 A mass of hexamethylene diamine-adipic acid polymer fibres similar to those of Example I was taken fron a normal industrial spinning operation.

The mass was divided into several samples comprising smaller masses, some of which were coated with the 20biguanide composition of Example 1 by dipping each fibre mass into a 2.5 wt.% aqueous solution of the biguanide of Example 1 for one hour at 55 0 C. The fibre masses were removed from the hot biguanide solutions and remained hot for about ten minutes.

2 5 Each mass was dried overnight at room temperature (23 0 The level of coating on the fibre was measured by a method of completely hydrolyzing the coated biguanide in an acidic aqueous solution followed by high performance liquid chromatography and was determined to be 1.0 Both coated and control samples of the fibre were bleached with hydrogen peroxide and sodium hypochlorite bleach solutions under conditions as outlined in Example 1.

It is believed that during the period when the fibr immersed in the coating bath at 55 0 °C the guanide DC-2092 9 mnigrates to the fibre surface, anc3 both in the ocoating bath and after removal from the bath when tho hot fibre mass is exposed tro air i.n the laboratory, the guanide reacts with reactive,, groups on tho fibre sut-face 1 and thus the cjUanide cures in--place on the I.i bre s; The results shown in Tab-le 2 illustrate the erformance of die--coated fibres compared to uncoated fibr-,s bleached in the bleaching bath containing the biguanide according to the prior art process, The orocess of the invention is thus shown to be more useful in preventing degradation of the -Dolyarnide 1fib~res than the prior art, particularly in hypochiorite bleach environments.

0 0 010 0 0 0 Table 2 Percentage Retention of Original Fibre 00 0Properties After Bleaching -Second Sample o 0 0 1 Dip Untreated Biguanide Prorertv Coated F ibre in Bleach 0 Hydrogen Peroxide Bleach Breaking Strength +4 -30 =8 ElongatLion at Break 0 -57 -34 000 20 Tenacity .4 -30 0 0 0 0 aSodiumn Hypochlorite Bleach 0 00 Breaking Strength +2 -25 Elongation at Break .11 -45 Tenacity 4-2 -25 -28 Example 3 Several sample masses of hexamethylene diamine-adipic acid fibres similar to those of Example I we?:e coated with the biguanide composition of Example I under t;-he conditions outlined in Example 2. The samples were subjected to hydrogen peroxide bleaching treatment as outlined in Example I, for 2 hours. One-half of the bleached samples, after being dried, were subjected to a second bleaching treatnient under t7he same conditions. Table 3 illustrates the DC- 209 2 10 11 performance uf thoi cjated fibres compared to that of the uncoated fibres treated repeatedly in the hydrogen peroxide bleaching bath. Table 4 illustrates the offect of the bleaching on polyhexamethylene adipamide fibre molecular weight and carboxyl ends. It is believed that when chemical degradation of the Spolyamide occurs, the polymer chain scission results in a reduction of the molecular weight of the polymer (as indicated by its relative viscosity) and an increase of carboxyl end groups. There is also a concomitant deterioration of physical properties of the fibre, reflected in a reduction of its breaking strength, elongation at break and tenacity, as well 0 00o00 as other properties. It is seen from the good 0 0 o 0a performance of the coated fibres that the biguanide oo a o °o coating remains on the fibre after the first bleacho o 15 co o ing cycle. It is thought that the cured coating will oo o 0 oo. remain on the fibre through many bleaching cycles.

o This conclusion is supported by the low change of relative viscosity and carboxyl end groups count.

o Table 3: Percentage Change in Properties 0 °oo 20 After Repeated Bleaching in Hydrogen Peroxide 0 Property Untreated Fibre Dip Coated S_ 2 h 2+2 h 2 h 2+2 h Breaking Strength -30 -35 +4 -6 Elongation At Break -57 -58 +0 +14 Tenacity -30 -43 +4 -16.5 Table 4: Effect of Repeated Bleaching on Molecular Weight and Carboxyl Ends of Polyhexamethylene Adipamide with Biguanide Coating Property Unbleached Bleached in Hydrogen Peroxide Untreated Fibre DiD Coated 2 h 2+2 h 2 h 2+2 h Relative Viscosity 50,6 44.2 41.0 48.5 48.9 Carboxyl End Groups 83.9 97.9 104.,6 79,3 84.5 DC-2092 11 EX amplIe 4; Tho sample s with bicguaniOd2 (;eating montioned in B--xample 3 were subjected t a hydrogen peroxidc, bleaching under the same ,:'onditions as E~xample 2 except that the pH of the bleach bath war, adjusted t%-o 0.i The results are illustrated i~ Table 5 below, Table 5: Percent Change in Fibre Properties After Bleaching in Hydrogen Peroxide at pH, Propertii 'Dip Coated Untreated Fibre Breaking Strength -i3 -4: Eloncation at Break J-l2 TJenacity 0 o 0 These results illustrate ta.the guanide coating is 00 0 o00 effective in both acidic and basic hydrogen peraxide o 0 1-9~ bleachning condition.-,, o0 0 O.-o0 xample The sam-ples with bicuanicie coating rzon-tioned 0o 00 0 0:00 20 in E:arnple I were subjected to a test in which the 000 Da e wer exoe to chorine at a concentration of: 1000 ppm at pH 4.5 and -751C for four hours., For o .00 0 tIhe polyamide staple coatezd with 0.2 wt. of the biguanide composition, the average loss in tonacity after exposure is 48 percen~t loss as compared to percent loss for the untreated Fibre.

Example 6 A finish free 18E3cO~e LYCRA spandox~ fibrea mass was dipped into a 1.5 wtaqueous solution of)S the guanide for one hour at 55 0 The fibre massots were removed from the hot guanide solution and DC- 2 09 2 -1 12 i ~rd 1I1II- a i 0o4 o C a 00 o 0 o 9 1 00 o tl 13 remained hot for about ten minutes. Each mass was dried overnight at room temperature (23 0 The level of coating on the spandex fibre was measured by the method described in Example 2. As discussed in Example 2, it is believed that during the period when the fibre is immersed in the coating bath at 55 C, the guanide migrates to the fibre surface, and both in the coating bath and after removal from the bath when the hot fibre mass is exposed to air in the laboratory, the guanide reacts with reactive groups on the fibre surface, and thus the guanide cures in place on the fibre.

The coated sample and an uncoated control sample were each bleached in hot aqueous sodium hypochlorite solution (90 0 C, pH 10, NaOCI 0.45%) for two hours. The coated sample showed a complete retention of physical strength whereas the control sample showed a loss of 30% of physical strength.

The test to determine strength is a standard Instron elastomer test. The method characterizes the tensile proe;tries of spandex fibre under conditions simulated to garment preparation and wear. A yarn sample is streched to various extension lengths and the stretch loads are measured at these various fixed extension lengths to determine the "physical strength" of the fibre under the specific conditions.

The break strength is the load required to break the fibre after the fibre had been stretched to 300% of its original length for five times.

The bleached coated and control samples were air dried and subjected to a second bleach in sodium hypochlorite solution under the same conditions for an additional 2.5 hours. After the second chlorine bleaching, the coated sample showed a complete retention in break strength whereas the control sample showed a 50% loss in strength. The coated sample also showed a 60% improvement in load at 300% elongation compared to the control sample.

DC-2092 13 14 Example 7 A finish free 1880 dtex LYCRA spandex fibre mass was dipped into a 1.5 wt.% aqueous solution of the guanide for one hour at 55 0 C. The fibre masses were removed from the hot guanide solution and remained hot for about ten minutes. Each mass was dried overnight at room temperature (23 0 The level of coating on the spandex fibre was measured by the method described in Example 2, As discussed in Example 2, it is believed that during the period when the fibre is immersed in the coating bath at 550C, the guanide migrates to the fibre surface, and both ooo0 in the coating bath and after removal from the bath oo o when the hot fibre mass is exposed to air in the 0 00 o "laboratory, the guanide reacts with reactive groups oo a 15 O 0 0 on the fibre surface, and thus the guanide cures in 0 o S000o place on the fibres.

ooo The coated sample and an uncoated control o 0 sample were each bleached in hot aqueous sodium hypocnlorite solution (90 0 C, pH 10, NaOC1 0.45%) o oO 20 000 for two hours. The physical strength of the fibres o oh 0 00 0oO was determined by measuring the load at 300% elongation at the first and fifth cycles of elongation. The coated sample showed a complete retention of physical strength whereas the control sample showed a loss of more than 40% of physical strength. The coated sample showed an 88% retention in break strength whereas the control showed only a retention.

The bleached coated and control samples were 0 air dried and subjected to a second bleach in sodium hypochlorite solution under the same conditions for an additional 2.5 hours. After the second chlorine bleaching, the coated sample showed a 70% retention DC-2092 14 15 in physical strength whereas the control sample showed only a 30% retention in strength. In addition, the coated sample showed an 85% retention of its original break strength whereas the control sample showed a 36% retention of break strength.

Without wishing to be bound by a technical explanation of the protection process, compositions and products disclosed herein, it is believed that upon heating, the guanide compound bonds with reactive groups on the polymer article, and itself polymerises to change from a substance soluble in water, alcohol and acetone, melting at about 144 to 147 0 C in the case of N-(2-methylphenyl)imidocarbonimidic diamide, to an 0 0 oo o insoluble substance that does not melt at o 0 temperatures up to 200 0 C. The polymer formed by o 0 15 oa polymerization of the guanide has a glass transition 0o temperature between 45 and 90 0 C. The longer the oo.0 guanide is subjected to heat and the higher the temperature, the higher is the glass transition temperature, suggesting that a cross-linking reaction 20 0oO 2 is occurring. When heated as a coating on polymers, O the ouanide is believed to cross-link with itself as well as to react with the reactive groups of the 0 00 0. polymers and thus to form very adherent coating.

Further, in combining with the reactive groups of the polymers, the coating not only acts as a barrier but 0000 o0 0 also effectively makes unavailable those reactive groups, and thus prevents by two means the cracking and embrittlement of the polymer that would otherwise occur.

In a proton NMR spectrum of the guanide described in Example 1 which has been heated mildly and remains slightly soluble, the patterns in the aromatic and methyl regions are very different as DC-2092 15 -16 compared to the unheated guanide, leading to the conclusion that not all of the tolyl rings are the same. This difference could be due either to stereochemical differences, for example tacticity, or to changes in the substitution pattern from ortho to meta and/or para. The aromatic to aliphatic hydrogen ratio is nevertheless about 4:3, indicating that the tolyl ring is not involved in the thermally induced reaction of the guanide.

From the results shown above it is clear that the guanide coating is effective to provide Schemical resistance to the fibre in both acidic and alkaline hypochlorite environments, as well as acidic 0aooo and alkaline peroxide environments.

o 0 o0 o An advantage to the process of the invention 0 0 0 0 00 i o° is that it provides a treated polymer article which o o 15 0 0 1 is resistant to oxidative degradation of its surface 00 ioo in aqueous peroxide and hypochlorite bleaching 0 environments without further necessity for incorporating treating agents into the bleaching solution. Another advantage is that the article 20 2 appears to have greater abrasion resistance after ,e exposure to bleaching solutions.

DC-2092 16

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Claims (15)

1. A process for protecting an article made from a polymer against degradation through exposure to aqueous solutions containing peroxygen groups, hypochlorite groups or mixtures thereof, said process comprising: coating said article with a composition comprising a reactive guanide compound, and curing said coated article s; O- co-pos on wherein the guanide compound is of the formula: NH i II w R 1 -NH-(-C-NH-)n-R 2 0 where n is from 2 to 10, R 1 has from 6 to 15 carbons and is either an alkyl, a cycloalkyl, a monocyclic aryl, or an alkyl-substituted monocyclic aryl and R 2 has a 000 not more than 15 carbons and is either hydrogen, an alkyl, a cycloalkyl, a monocyclic aryl, or an alkyl-substituted monocyclic aryl.

2. The process of claim 1 wherein said polymer is selected from (i) S spandex and (ii) condensation polymers formed from monomers selected from the group consisting of dicarboxylic acids, diamines, aminoacids and diols, said monomers being aliphatic or monocyclic aromatic.

3. A process as claimed in claim 1 or 2, wherein said guanide compound is selected from 1-phenylbiguanide; 1-(2-tolyl)biguanide; and salts thereof.

4, A process as claimed in claim 1 or 2, wherein said guanide compound is selected from 1-(N-hexyl)-biguanide; 1,5-(N-hexyl)-biguanide; 1-(cyclohexyl)- biguanide and

5 A process as claimed in any one of claims 1 to 4, wherein said articles are selected from the groip consisting of fibres, monofilament and film.

6, A, process as claimed in any one of claims 1 to 5, wherein said articles -16 I are made of polymers selected from the group consisting of polyamides and polyesters.

7. A process as claimed in any one of claims 1 to 6, wherein said coating step is accomplished by either spraying or dipping.

8. A process as claimed in any one of claims 1 to 7, wherein said curing step is accomplished by heating the coating on said article to a temperature of from 100 C to 120 C for from 3 to 10 minutes.

9. A process as claimed in any one of claims 1 to 8, wherein said composition comprising a reactive guanide compound is an aqueous sizing composition. An article selected from the group consisting of fibres, film and monofilament, said article being made from a polymer and coated with a t 00 I composition comprising a reactive guanide compound of the formula: NH I I R-NH-(-C-NH-)n-R2 S where n is from 2 to

10, R 1 has from 6 to 15 carbons and is either an alkyl, a cycloalkyl, a monocyclic aryl, or an alkyl-substituted monocyclic aryl, and R 2 has Snot more than 15 carbons and is either hydrogen, an alkyl, a monocyclic aryl, or an alkyl-substituted monocyclic aryl, said article being cured after being coated with said composition.

11. An article as claimed in claim 10 wherein said polymer is selected from spandex and a condensation polymer formed from monomers selected from the group consisting of dicarboxylic acids, diamines, aminoacids and diols, said monomers being aliphatic or monocyclic aromatic.

12. An article as claimed in claim 10 or 11; said article being cured by heating to a temperature from 100 to 120'C for from 3 to 10 minutes. L 13. g -g mp or-3fomr t. fIgs^- m .np m a; plym er. C.. 17

13. The article as claimed in any one of claims 10 to 12, substantially as described herein with reference to any one of the Examples.

14. The process as claimed in any one of claims 1 to 9, which process is substantially as described herein with reference to any one of the Examples.

15. The product whenever prepared by the process of any one of claims 1 to 9 or 14. 0 00 0 00 oo 0 C 0 a o o 00 0 0 0 0 00 0 0 0a 0 000000 0 0 DATED this 16th day of November 1990. DU PONT CANADA, INC. By their Patent Attorneys: CALLINAN LAWRIE a a 0 a 0a 0000 00 I C jlj ii I /I a: -18- 1