A C-13 NUCLEAR-MAGNETIC-RESONANCE STUDY OF THE EFFECT OF TEMPERATURE ON THE SIDE-CHAIN POLYSILOXANE LIQUID-CRYSTAL CONTAINING TRANS-2-[PARA-(1-UNDECANYL-11-OXY)PHENYL]-5-[(PARA-2(S)-METHYL-1-BUTOXY)PHENYL]-1,3-DIOXANE

被引：6

作者：

PERRY, BC ^{[1
]}

HAHN, B ^{[1
]}

PERCEC, V ^{[1
]}

KOENIG, JL ^{[1
]}

机构：

[1] CASE WESTERN RESERVE UNIV,DEPT MACROMOLEC SCI,CLEVELAND,OH 44106

来源：

POLYMER | 1990年 / 31卷 / 04期

关键词：

liquid crystals; n.m.r; spectroscopy; temperature effects;

D O I：

10.1016/0032-3861(90)90295-A

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

Solid-state 13C nuclear magnetic resonance has been used to study the effects of temperature cycling on a side-chain polymer liquid crystal. Cycling the polymer from 100°C to room temperature resulted in severe line broadening. High-resolution spectra were obtained by cycling from 70°C to room temperature. The dioxane ring undergoes a transition from a mixture of cis and trans to an all-trans conformation in the liquid-crystalline state. The line broadening is associated with enhanced mobility of the mesogenic unit and decreased mobility of the backbone. T1 measurements indicate that the mesogenic unit and the spacer carbons in α positions with respect to the mesogen are rigid below Tm. © 1990.

引用

页码：721 / 727

页数：7