Diffusion Studies of Model Thermotropic Polymers

9321573其他热致性主链聚醚将以氘化和未氘化形式制备，作为模型聚合物，用于研究液晶（LC）聚合物熔体中的扩散行为。目标聚合物将被制备成具有足够高分子量的持续长度范围，以形成各向同性状态的纠缠熔体。这些聚合物的中间相性质将被评估。将采用前向反冲光谱法（FRES）来确定这些互扩散的LC聚合物链的浓度分布。小角中子散射将用于确定旋转半径的各向异性比和持续长度。支化LC聚合物将通过链的末端连接来制备。计划与工业科学家合作，利用流变学测量进一步表征这些热致性聚合物。从这些研究中获得的基本信息将有助于更好地了解LC聚合物的熔体特性。＊＊＊

9321573 Ober Thermotropic main-chain polyethers will be prepared in both deuterated and undeuterated forms as model polymers for the investigation of diffusion behavior in liquid crystalline (LC) polymer melts. The target polymers will be prepared with a range of persistence lengths with sufficiently high molecular weights to form entangled melts in the isotropic state. The mesophase properties of these polymers will be evaluated. Forward recoil spectrometry (FRES) will be sued to determine the concentration profiles of these interdiffusing LC polymer chains. Small-angle neutron scattering will be used to determine the anisotropy ratio of the radius of gyration and the persistence length. Branched LC polymers will be prepared by endlinking chains. Collaborations with industrial scientists are planned, which will further characterize these thermotropic polymers using rheological measurements. The fundamental information derived from these studies will be useful for providing a better fundamental understanding of the melt properties of LC polymers. ***