HIPS/PP反应共混物的热性能研究

STUDY ON THE THERMAL PROPERTIES OF THE REACTIVE BLENDS OF HIGH IMPACT POLYSTYRENE AND POLYPROPYLENE

研究了高抗冲聚苯乙烯（ＨＩＰＳ）／聚丙烯（ＰＰ）在过氧化二异丙苯（ＤＣＰ）存在下熔融反应共混物的热学性能。ＨＩＰＳ在ＤＣＰ存在下以ＰＳ的降解为主，ＰＳ的Ｔｇ明显下降，ＰＰ在ＤＣＰ存在下也以降解为主，ＰＰ的结晶完善性受到破坏，ＨＩＰＳ／ＰＰ共混物在ＤＣＰ存在下以ＰＰ同ＨＩＰＳ的反应接枝为主，分子运动的特征及热性能较前两者发生明显变化，ＰＳ的Ｔｇ略有下降，ＰＰ分子链的规整性降低，结晶熔点降低，完善性变差。

The glass transition temperature, crystallization and melting behaviour of the reactive blends of high impact polystyrene(HIPS)/polypropylene(PP)/dicumyl peroxide(DCP) were studied by means of DSC. The degradation of HIPS during the melt mixing with DCP was concluded from the reduction of the glass transition temperatures of PS. The variation on the DSC traces of PP/DCP mixtures showed that the melting temperatures of PP were decreased and the single melting peak was split into the double ones which resulted from the scission of PP molecular chains. The grafting copolymers of HIPS and PP were synthesized in situ during the mixing of HIPS/PP/DCP. The reactive blending of HIPS/PP/DCP was carried out and the grafting copolymer of HIPS/PP was characterized by the combination feature of DSC traces and the infrared spectra.