Process for manufacture of high molecular weight polyester resins from 2,6-naphthalene dicarboxylic acid.

摘要

Prepn. of the polyester resin comprises: (a) reacting in a first step or zone 2,6-naphthalene dicarboxylic acid (I) with a molten prepolymer deriv. from a glycol and (I) to form a low mol.wt. prod.; (b) reacting the prod. with a glycol in at least 2 successive steps or zones of glycol addn. to form a prepolymer; and (c) polymerising at least part of the prepolymer to form a polyester with a mid-point glass transition temp. (Tg) above 123 deg.C.. The prepolymer is pref. formed using 1,2-ethanediol or 1,4-butanediol at 200-300 deg.C. 1,2-ethanediol is pref.. the polyester is pref. poly(ethylene-2,6-naphthalate) (II) of Tg above 124 deg.C.