THEORETICAL AND GENERAL

摘要

Primary OH functional hyperbranched polyester has been prepared from 5-hydroxymethyl-l,4-dioxan-2-one as pictured below.This was synthesised from 5-hydroxy-2-phenyl- 1,3-dioxane treated with ethyl bromo acetate.The acetal moiety was hydrolysed with dilute ethanol solution of HC1,the polymer produced being thermally depolymerised using the reaction procedure described.Certain literature procedures were followed without modification.Polymerisation was with stannous octoate or 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU)at 75-110 deg C for up to 3 days.Reaction conditions for a number of polymerisations are tabulated.Polymers were prepared with Mns up to 88,000,with MW distributions of 2.Characterisation was by GPC,NMR and MALDI-TOF.Model compound studies are reported.