摘要
利用正电子湮没技术对侧链型热致高分子液晶丙烯酸酯共聚物进行了变温相变研究．除实验标识出样品的相变温度点外，根据试样中自由体积随温度的变化关系，对高分子液晶材料内部立链、侧链以及介晶基元的相变行为特点进行了探讨，并就与小分子液晶变化特点的一些不同做了解释．
The results of positron annihilation studies on the side－chain polymer liquid crystals were obtained as afunction of temperature． It is indicated that thermotropic liquid crystal has two phase transition points near 40℃ and 76℃ respectively． It is suggested that the first phase transition point is correspondent to the melting point of specimen and the second one is clearing point at which liquid crystal phase transits isotropic liquid phase． It can be concluded by the changes of Free－Volume at the phase transition points that the smectic state SA is in better ordered state than the other liquid crystals. The diffrence in the curves of o-Ps life－time with temperature between the liquid crystal and the liquid crystal polymer was explained．
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
1996年第8期688-692,共5页
Acta Physico-Chimica Sinica
基金
国家自然科学基金
中国科学院八五重点项目
关键词
正电子湮没
液晶
丙烯酸酯共聚物
相变
Positron annihilation,Liquid crystal polymer,Free-Volume
