Patent ID: 6812324
Filing Date: 2004-11-02
Classification: C08G

Abstract:
A method for preparing nylon 6 copolymer containing 5-sulfoisophthalate salts comonomer, comprising:i. Reacting (A) 5-sulfoisophthalate salts ester (formula I) with (B) aliphatic diamine (formula II)NH2(CH2)nNH2â€ƒâ€ƒ(formula II) in a molar ratio of 2Ëœ30, followed by completely removing the unreacted aliphatic diamine, to obtain (E) 5-sulfobenzenediamide compound (formula III); ii. Reacting (C) caprolactam with (D) aliphatic diacid (formula IV) HOOC(CH2)nCOOHâ€ƒâ€ƒ(formula IV) to form an oligomer with low molecular weight; andiii. Adding (E) 5-sulfobenzenediamide (formula III) and catalyst to the oligomer obtained in step (ii) to cause a polymerization reaction to obtain nylon 6 copolymer containing 5-sulfoisophthalate salts comonomer, wherein R is â€”(CH2)nH and n is a positive integer of 1Ëœ6 in formula I; n is a positive integer of 1Ëœ12 in formulas II, III and IV; M is Li, Na or K in formulas I and III; the molar ratio of E/C is 0.005Ëœ0.150; and the molar ratio of D/E is 1.05Ëœ1.00.