X-RAY-DIFFRACTION STUDY OF SIDE-ON FIXED HOMOPOLYSILOXANES FROM NEMATIC TO SMECTIC-C PHASES

被引：41

作者：

ACHARD, MF ^{[1
]}

LECOMMANDOUX, S ^{[1
]}

HARDOUIN, F ^{[1
]}

机构：

[1] UNIV BORDEAUX 1, CTR RECH PAUL PASCAL, F-33600 PESSAC, FRANCE

来源：

LIQUID CRYSTALS | 1995年 / 19卷 / 05期

关键词：

D O I：

10.1080/02678299508031071

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The X-ray patterns for the nematic phase in a series of side-on fixed polysiloxanes show different kinds of diffuse elements which imply complex short range ordering. A systematic structural study of the evolution of the patterns versus two molecular parameters, namely the spacer length and the length of the terminal aliphatic tails, suggests the possible occurrence of a smectic C phase for certain values of these parameters. Taking into account these tendencies, new synthesis led to a nematic-smectic C polymorphism observed for the first time in side-on fixed polysiloxanes.

引用

页码：581 / 587

页数：7

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