Production of aromatic polyesters of improved colour
Abstract
Abstract IN THE PRODUCTION OF HIGHLY POLYMERIC POLYESTERS OF AROMATIC DIACARBOXYLIC ACIDS AND ETHYLENE GLYCOLS BY THE POLYCONDENSATION OF POLYCONDENSABLE MATERIAL AT LEAST 85 MOLE PERCENT OF WHICH CONSISTS OF AT LEAST ONE BIS ETHYLENE GYCOL ESTER OF AN AROMIC DICARBOXYLIC ACID ESPECIALLY BIS ETHYLENE GLYCOL TEREPHTHALATES THE USE OF A CO-ORDINATION COMPOUND OF A TRIVALENT ANTIMONY COMPOUND AN AN ORGANIC OXO COMPOUND OF PHOSPHORUS OR ARSENIC AS POLYCONDENSATION CATALYST LEADS TO PRODUCTS HAVING A REDUCED TENDENCY TO A GREY DICOLOURATION COMPARED WITH THOSE PREPARED USING CONVENTIONAL ANTIMONIAL CATALYSTS. THE PREFERRED CATALYSTS ARE COORDINATION COMPOUND HAVING THE STRUCTURE ((R-)2-M(:O)-R1-M(-R)2(:O)) SB(-Y)3 WHERE EACH M IS PHOSPHORUS OR ARSENIC, EACH R IS HYDROCARBYL OR HYDROCARBYLOXY R1 IS A DIRECT LINK OR A DIVALENT HYDROCARBON GROUP, ESPECIALLY -CH2- OR -CH2CH2-, AND Y IS AN ANION, ESPECIALLY HALIDE.
Inventors
- 👤 Warren Hewertson
Bibliographic Details
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