X-Ray and Neutron Scattering Studies of Structure and Fluctuation Phenomena in Side Chain Polymer Liquid Crystals

侧链聚合物和弹性体液晶是一种新型材料，它独特地结合了两种竞争现象；聚合物的各向同性波动和液晶的各向异性取向和平动顺序波动。他们展示了新颖的向列型液晶结构和相变，为未解决的向列-近晶- a问题提供了新的视角。在这些体系中，聚合物链所探索的空间维数的变化应该随着近晶秩序的建立而发生，并伴随着四个相关长度尺度之间有趣的交叉行为。这为实验研究二维随机线圈的统计力学提供了机会。这方面的综合和初步研究大多是在美国以外进行的。他们提出结合两种强大的技术，高分辨率x射线衍射和小角度中子散射，来研究这些材料的结构和关键现象的微妙方面。他们提出的研究应该有助于把这个有趣的领域带入这个国家凝聚态研究的主流。

Side chain polymer and elastomer liquid crystals are new classes of materials which uniquely combine two competing phenomena; isotropic fluctuations of polymers and anisotropic orientational and translational order fluctuations of liquid crystals. They exhibit novel nematic liquid crystalline structures and phase transitions, and offer a new perspective on the unsolved nematic- smectic-A problem. A change in the number of spatial dimensions explored by the polymer chain should occur with the establishment of smectic order in these systems accompanied by an interesting cross-over behavior among four relevent length scales. This provides an opportunity to experimentally study the statistical mechanics of a random coil in two dimensions. The synthesis and preliminary studies in this area have been performed mostly outside the United States. They propose here a combination of two powerful techniques, high-resolution x-ray diffraction and small-angle neutron scattering, to study subtle aspects of the structure and critical phenomena in these materials. They proposed research should help bring this interesting area into the main stream of condensed matter research in this country.