There is disclosed an aromatic polyester-polyorganosiloxane block copolymer constituted of a polyester segment constituted mainly of:
(a) an aromatic polyester constituted of an aromatic dicarboxylic acid and a dihydric phenol, a lower aliphatic diol or an alicyclic diol,
(b) an aromatic polyester constituted of an aromatic hydroxycarboxylic acid,
(c) a copolymer constituted of (a) and (b), and a polyorganosiloxane segment having a recurring unit represented by the following formula:
(in this formula, R₁, R₂ and R₃ means the groups as specified in the specification) of which bonding part between the polyester segment and the polyorganosiloxane segment is an ester linkage formed by a condensation reaction between the terminal carboxyl group of the polyester segment and the terminal hydroxyl group of the polyorganosiloxane segment.
本发明公开了一种芳香族聚酯-聚有机
硅氧烷嵌段共聚物,其聚酯段主要由以下成分构成
(a) 由芳香族二
羧酸和二元
酚、低脂二元醇或脂环二元醇构成的芳香族聚酯、
(b) 由芳香族羟基
羧酸构成的芳香族聚酯、
(c) 由(a)和(b)以及具有下式所示递归单元的聚有机
硅氧烷段构成的共聚物:
(在该式中,R₁、R₂ 和 R₃ 指说明书中规定的基团),其中聚酯段和聚有机
硅氧烷段之间的结合部 分是聚酯段的末端羧基和聚有机
硅氧烷段的末端羟基通过缩合反应形成的酯连接。