Verfahren zur Herstellung von Polyesteramiden

摘要

1,138,298. Polyesteramides. MONSANTO CO. 1 April, 1966 [21 April, 1965 (2)1, No. 14581/66. Heading C3R. Polyesteramides of the formula wherein R is an aliphatic or cycloaliphatic radical and A is a p-phenylene or 2 : 6-naphthylene radical, provided that A cannot be a p-phenylene group when R is an ethylene group, are prepared by reaction of terephthalic acid diamide N : N1 - di - # - caproic acid or 2 : 6- naphthalene dicarboxylic acid diamide N : N1- di-#-caproic acid or an ester-forming derivative thereof with an excess of an aliphatic or cycloaliphatic diol, in the presence of a polycondensation catalyst. The diamide di-caproic acid or, e.g. its dimethyl ester may be obtained by reaction of the dicarboxylic acid dihalide with #-caproic acid or, e.g. its methyl ester. Suitable glycols are ethylene, propylene, butylene and cyclohexane dimethylene glycols. Usually the di-(glycol ester) is first formed at, e.g. 175-195‹ C. This may be kept if required, or prepared by a different route, e.g. using ethylene oxide. Then polycondensation is brought about at higher temperatures, e.g. 230-250‹ C. and pressures of, e.g. 0À1-5 mm. Hg. Preferred catalysts are sodium hydrogen titanium hexaisopropoxide and zinc acetylacetonate, in amounts of, e.g. 0À001-2 wt. per cent of the acid. In Example 1 dimethyl 2 : 6 naphthalene dicarboxylic acid diamide N : N1- di-#-caproate (from the acid dichloride and caprolactam-1 : 2 molar ratio-followed by esterification with methanol) is condensed with ethylene glycol i.p.o. zinc acetylacetonate. In Example 2, terephthalic acid diamide N : N1-di-#-caproic acid (from aqueous sodium caproate and terephthalyl chloride in CHCl 3 ) is esterified with methanol and reacted with cyclohexane dimethylene glycol i.p.o. sodium hydrogen titanium hexaisopropoxide.