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首页> 外文期刊>Journal of Macromolecular Science. Pure and Applied Chemistry >Synthesis and Characterization of H-bonded Side-Chain Liquid-Crystalline Polysiloxanes
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Synthesis and Characterization of H-bonded Side-Chain Liquid-Crystalline Polysiloxanes

机译：氢键侧链液晶聚硅氧烷的合成与表征

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摘要

Smectic Liquid-crystalline (LC) polysiloxanes P1 P7 were prepared using cholesteryl 6-undec-10-enoyloxy-naphthalene-2-carboxylateand cholesteryl 3-sulfo-4-undec-10-enoyloxy-benzoate in a one-step reaction with sulfonic acid group contents ranging between 0 andwt 4.39%. With an increase of sulfonic acid groups, the glass transition temperature rose slightly; while the temperature of clear pointdecreased. As sulfonic groups increased, H-bonding interaction strengthened, resulting in an increase of glass transition temperature. Onthe other hand, aggregates of H-bond derived from sulfonic acids would destroy the homogeneous rigid moieties and the high-ordered struc-ture, resulting in a temperature of clear point decreased. In X-ray measurement, all the polymers displayed sharp strong peaks around20 ti 2.6° and broad peaks around 2θ≈16.6°. The broad peaks at wide-angle are similar, but there is great different at low angles. Forthe polymer without sulfonic acid, the only one strong peak at low angle indicates high-ordered lamellar structure due to homogeneousrigid moieties. For the polymers containing more sulfonic acid, two sharp peaks appeared at low angles, and the intensities of these twopeaks varied. With increase of sulfonic acid groups in the polymer systems, the hydrogen-bonding aggregates in domains would dividethe homogeneous rigid mesogens into two kinds of nanophases, that is, one containing non H-bond mesogens and another involvingH-bonding aggregated mesogens. These two different nanophases result in different lamellar spacings.
机译：使用胆甾醇基6-十一烷基-10-烯氧基氧基萘-2-羧酸酯和胆甾醇3-磺基-4-十一烷基-10-烯氧基氧基苯甲酸酯与磺酸一步反应制备了近晶液晶（LC）聚硅氧烷P1 P7组含量在0至4.39％之间。随着磺酸基团的增加，玻璃化转变温度略有上升。晴点温度下降。随着磺酸基团的增加，氢键相互作用增强，导致玻璃化转变温度升高。另一方面，源自磺酸的H键的聚集体会破坏均相的刚性部分和高阶结构，从而导致透明点温度降低。在X射线测量中，所有聚合物在20 ti 2.6°附近均显示出尖锐的强峰，而在2θ≈16.6°附近则显示出宽峰。广角处的宽峰相似，但低角度处的峰相差很大。对于不含磺酸的聚合物，由于均质的刚性部分，在低角度只有一个强峰表明层状结构较高。对于含更多磺酸的聚合物，低角度出现两个尖峰，并且这两个峰的强度变化。随着聚合物体系中磺酸基团的增加，域中的氢键聚集体会将均质的刚性介晶分为两种纳米相，即一个包含非氢键介晶的纳米相，另一个包含氢键键合的介晶的纳米相。这两个不同的纳米相导致不同的层状间距。

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