摘要
在温度280℃附近对含有液晶共聚酯P-Hydroxy Benzoic Acid/Poly(-Ethylene Terephthalate-)PHB/PET和Poly(-Ethylene Terephthalate-)PET的共混样品进行热处理时,发现共混物的熔点随热处理的时间增加而不断降低,热处理温度越高,相同时间内共混物熔点下降程度越大;而具有相同热历史的纯PET样品熔点几乎保持不变.通过NMR方法证实了PHB/PET-TET共混物熔点随热处理时间下降是由于PHB/PET和PET之间发生了酯交换反应.所以可根据共混物的宏观热性质和PHB/PET序列结构变化表征PHB/PET和PET共混物之间的酯交换程度.
When the blends containing PHB/PET liquid crystal copolyester and PET were annealed near 280癈, it was found that the melting point of the blends decreased with the annealing time. If the annealing time was kept constant, the higher annealing temperature resulted in lower melting point. However, the melting point of the pure PET which had the same annealing history was almost not changed. It was demonstrated by NMR that the melting point decrease of the blends during annealing process was due to the transesterification between PHB/ PET and PET. Therefore, the extent of transesterification of the blends can be estimated according to the thermal-properties of the blends and the change of the PHB/PET sequence structure.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
1993年第2期189-194,共6页
Acta Polymerica Sinica
基金
博士点基金
