| 摘要 |
In the manufacture of linear aromatic polyesters by the polycondensation of bis-(hydroxyalkyl)-esters of aromatic dicarboxylic acids, there is used as a catalyst an antimony or boron glycol compound of formula Sb2(O-CH2-CH2-O)3 or B2(O-CH2-CH2-O)3 The catalysts are made by heating antimony oxide or boron oxide with ethylene glycol (see Group IV (b)). When the bis-(hydroxyalkyl)-ester is made by effecting ester-interchange between a dialkyl ester of an aromatic dicarboxylic acid and a glycol, there may be used as ester-interchange catalyst zinc oxide, zinc acetate or litharge. In examples, polyesters, some of which are fibre-forming, were made by reacting (1), (2), (3), (9) and (13) dimethyl terephthalate and ethylene glycol; (4) dimethyl terephthalate and 1 : 4-butane diol; (5) and (6) dimethyl terephthalate, ethylene glycol and 1 : 4-butane diol; (7) the dimethyl ester of di-(p-carboxyphenyl)-sulphone and hexane diol; (8) the dimethyl ester of o-carboxy hydrocinnamic acid and ethylene glycol; (10) dimethyl terephthalate, dimethyl isophthalate and ethylene glycol; (11) the dimethyl ester of di-(p-carboxybenzyl)-sulphone, ethylene glycol and diethylene glycol; (12) dimethyl terephthalate, the dimethyl ester of di-(p-carboxyphenyl)-sulphone and ethylene glycol. The Provisional Specification describes the preparation of a polyester from dimethyl isophthalate and ethylene glycol. Specification 740,381 is referred to.ALSO:An antimony or boron glycol compound of formula <FORM:0805534/IV (b)/1> is made by heating antimony oxide or boron oxide with ethylene glycol. The compounds may be purified by recrystallization from ethylene glycol and washing with dioxane. They are used as catalysts for making polyesters (see Group IV (a)). Specification 740,381, [Group IV (a)], is referred to. |
