| 摘要 |
PROBLEM TO BE SOLVED: To produce, industrially easily, a high-mol.-wt. polyhydroxycarboxylic acid useful as a biodegradable polymer by reacting an acid chloride of a hydroxycarboxylic acid and/or its oligomer in the presence of a tert. amine. SOLUTION: One mol of an acid chloride of a hydroxycarboxylic acid and/or its oligomer of the formula (wherein R is an aliph. hydrocarbon group; and n is 1 or higher) is reacted at a temp. of 120 deg.C or lower in the presence of at least 1 mol, pref. 1-6 mol, of at least one tert. amine having a logarithm of the reciprocal of the acid dissociation constant of 4.9 or higher and selected from among quinoline, isoquinoline, quinaldine, 3,5-lutidine, 2,6-lutidine, 4- methylmorpholine, 2,4,6-collidine, tri-n-octylamine, N,N,N',N'- tetramethylethylenediamine, and N-methylpiperidine while the water content of the reaction system is being controlled so as to satisfy the relation: H<=1.8×M×10<-3> (wherein H is the number of moles of water; and M is the number of moles of the hydroxycarboxylic acid monomer).
|
