GB991554A - Process for the manufacture of linear polyesters - Google Patents

Abstract

Phosphorus-amido compounds having the formula <FORM:0991554/C2/1> in which X is an ester-forming group (e.g. carbomethoxy or acetoxy), A is a bivalent organic radical and R is an organic radical with a tertiary nitrogen atom, one valency of the nitrogen atom being attached to the phosphorus atom are made of (a) reacting phosphorus trichloride or phosphorus oxychloride with a secondary amine (e.g. dimethylamine, morpholine, piperidine or pyrrolidine) in a proportion such that one chlorine atom is exchanged, and (b) reacting one mol. of the resulting dichlorophosphane amide with an organic compound containing one free hydroxyl group and an ester-forming group (e.g. p-hydroxybenzoic acid methyl ester, p-(2-hydroxyethoxy)-benzoic acid methyl ester, vanillic acid methyl ester, 4-carbomethoxy - 41 - hydroxydiphenyl, p-carbomethoxy - a - naphthol, 4 - hydroxy - 41-carbomethoxy - diphenyl sulphone, monoglycol - monomethyl - terephthalate, g - hydroxybutyric acid methyl ester, monoacetyl-hydroquinone or p-(2-acetoxyethoxy)-phenol). Low molecular weight precondensate may be made by reacting the phosphorous-amido compound with a diol and/or an ester of a dicarboxylic acid. Examples describe the preparation of N-morpholino-di-(p-carbomethoxyphenyl)-phosphite or phosphate.ALSO:Linear polyesters of dicarboxylic acids and diols are given improved dyeability, good heat-resistance, reduced shrinkage and a reduced tendency to electrostatic load by modification with a phosphorus amido compound of formula <FORM:0991554/C3/1> where X is an ester forming group (e.g. carbomethoxy or acetoxy), A is a bivalent organic radical and R is an organic radical having a tertiary nitrogen atom of which one valency is attached to the phosphorus atom. Specified phosphorus compounds are those in which R is the residue of morpholine, piperidine, pyrrolidine or dimethylamine and A is the residue obtained by removal of the hydrogen atom from the hydroxyl group of p-hydroxybenzoic acid methyl ester, p-(2-hydroxyethoxy) benzoic acid methyl ester, vanillic acid methyl ester, 4-carbomethoxy-41-hydroxydiphenyl, p - carbomethoxy - a - naphthol, 4 - hydroxy - 41 - carbomethoxy-diphenylsulphone, monoglycol monomethyl terephthalate, g -hydroxybutyric acid methyl ester, monoacetyl hydroquinone and p - (2 - acetoxyethoxy) - phenol. Specified polyesters are those obtainable from terephthalic, isophthalic, 4:41-diphenyldicarboxylic, 4:41-sulphonyl benzoic or 4:41-stilbene dicarboxylic acids (possibly in admixture with sebacic or suberic acid) and ethylene glycol, di-, tri- or tetra-ethylene glycol, 1:4-dimethylolcyclohexane or 2:2-dimethyl-1:3-propanediol. The polyesters are made by reacting (a) the phosphorus-amido compound or a low molecular weight precondensate thereof with a diol and/or an ester of a dicarboxylic acid with (b) a diol and an ester of a dicarboxylic acid or a low molecular weight precondensate thereof. Ester-interchange catalysts (e.g. the acetates or benzoates of zinc, lead, cadmium or manganese) and polycondensation catalysts (e.g. the oxides of antimony, lead or bismuth) may be used. Examples describe the manufacture of fibre-forming polyesters by reacting dimethyl terephthalate and ethylene glycol together with (1) N - morpholino - di - (p - carbomethoxy-phenyl)-phosphite; (2) and (3) N-morpholino-di-(p-carbomethoxyphenyl)-phosphate, with or without dimethyl isophthalate.