Polytrimethylene terephthalate which has a low content of a cyclic dimer and hardly produces the cyclic dimer when it is melt molded and a fiber made from the polytrimethylene terephthalate.
Polytrimethylene terephthalate (A) is essentially composed of a trimethylene terephthalate unit, has an intrinsic viscosity of 0.5 to 1.6 dl/g and contains 0.01 to 0.5 wt% of a compound represented by the following formula (I) or (II):
(R1, R2 and R3 are the same or different hydrocarbon groups having 1 to 10 carbon atoms, n is an integer of 1 to 5, M is an alkali metal atom or alkali earth metal atom, and m is 1 when M is an alkali metal atom and 2 when M is an alkali earth metal atom),
(R4 and R5 are the same or different and each a hydrogen atom or hydrocarbon group having 1 to 10 carbon atoms).
聚
对苯二甲酸三亚甲基酯,其环状二聚体含量较低,在熔融成型时几乎不产生环状二聚体,以及由聚
对苯二甲酸三亚甲基酯制成的纤维。
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对苯二甲酸三甲酯(A)主要由
对苯二甲酸三甲酯单元组成,固有粘度为 0.5 至 1.6 分升/克,含有 0.01 至 0.5 重量百分比的下式(I)或(II)所代表的化合物:
(R1、R2 和 R3 为具有 1 至 10 个碳原子的相同或不同的烃基,n 为 1 至 5 的整数,M 为碱
金属原子或碱土
金属原子,当 M 为碱
金属原子时,m 为 1,当 M 为碱土
金属原子时,m 为 2)、
(R4 和 R5 相同或不同,各自为氢原子或具有 1 至 10 个碳原子的烃基)。