申请人:THE GLIDDEN COMPANY
公开号:EP0328950A1
公开(公告)日:1989-08-23
A protective surface coating composition containing a catalytic amount of a transesterification catalyst, where the coating composition contains a polymeric binder adapted to crosslink by transesterification upon heat curing, the coating composition comprising:
a polymeric binder containing hydroxyl functional groups and lower alkyl ester carboxylic ester functional groups adapted to transesterify and crosslink in the presence of a transesterification catalyst;
said transesterification catalyst comprising on the basis of 100 weight parts of said polymeric binder betwen 1 and 20 weight parts of catalytic epoxy compound containing oxirane functionality in combination with 0.1 to 10 weight parts of (a) a conjugate base of a weak acid comprising an inorganic cation salt, where the conjugate base of a weak acid has a pka between 2.5 and 14; or (b) an inorganic salt having an inorganic cation selected from sodium, potassium, lithium, calcium, and iron and an inorganic anion selected from a halogen, azide, cyanide or hydroxide;
where said polymeric binder is substantially free of carboxyl groups and is adapted to cure by transesterification.
一种含有催化量的酯交换催化剂的保护性表面涂层组合物,其中涂层组合物含有一种聚合物粘合剂,该聚合物粘合剂在加热固化时可通过酯交换反应发生交联,该涂层组合物包括:
聚合物粘合剂,含有羟基官能团和低级烷基酯羧酸酯官能团,在酯交换催化剂作用下可发生酯交换和交联;
所述酯交换催化剂以 100 重量份所述聚合物粘合剂为基准,包括 1 至 20 重量份含有环氧乙烷官能团的催化环氧化合物与 0.1 至 10 重量份的 (a) 弱酸共轭碱,包括无机阳离子盐,其中弱酸共轭碱的 pka 值在 2.5 至 14 之间;或 (b) 无机盐,其无机阳离子选自钠、钾、锂、钙和铁,无机阴离子选自卤素、叠氮化物、氰化物或氢氧化物;
其中所述聚合物粘合剂基本上不含羧基,可通过酯交换反应固化。