RUI: Phase Separation Behavior of Polymer Blends Modified by Copolymer Additives

RUI奖的重点是二元聚合物共混物中相分离的平衡热力学和动力学，以及各种共聚物结构和浓度的添加剂。 这项工作的目标是更好地了解共聚物如何影响相演变和热力学边界。 扩展以前的研究，散射和模拟技术将被采用。 待研究的共聚物包括无规、嵌段、多嵌段和接枝共聚物。 对于一些共聚物，共聚物的单体组成还将包括对称和不对称组成。 具体的实验三元体系是聚丁二烯、聚苯乙烯以及丁二烯和苯乙烯的各种共聚物的共混物。 均聚物的分子量分为两类，低分子量共混物和分子量大于缠结分子量的共混物。 这些系统将进行实验研究，在适当的情况下，使用温度跳跃广角光散射以及小角中子散射（SANS）技术。 最后，将采用Monte Carlo计算机模拟技术对实验聚合物体系进行建模。%通常通过混合现有材料来尝试开发具有定制特性的新的聚合物基材料。 成功的混合通常具有挑战性，为了帮助混合，通常引入添加剂作为增容剂。 在这项工作中，将研究各种增容剂对聚合物材料混合的影响，目的是更好地了解所涉及的基本过程。 随着对这些效应的更好理解，这些知识可以应用于工业系统，以改善聚合物基材料的加工和性能。

This RUI award focuses on equilibrium thermodynamics and kinetics of phase separation in binary polymer blends with additives of various copolymer structures and concentrations. The goal of this work is to better understand how copolymers can influence phase evolution and thermodynamic boundaries. Expanding on previous research, scattering and simulation techniques will be employed. The copolymers to be studied include random, block, multi-block, and graft copolymers. The monomer composition of the copolymer will also include both symmetric and asymmetric compositions for some of the copolymers. The specific experimental ternary system is a blend of polybutadiene, polystyrene, and various copolymers of butadiene and styrene. The molecular weights of the homopolymers will be in two classes, a low molecular weight blend and a blend with molecular weight greater than the entanglement molecular weight. These systems will be studied experimentally using temperature jump wide-angle light scattering as well as small angle neutron scattering (SANS) techniques when appropriate. Lastly, Monte Carlo computer simulation techniques will be employed to model the experimental polymer systems.%%%The development of new polymer-based materials with tailored properties is often attempted through the mixing of currently existing materials. Successful mixing has often been challenging to accomplish and to aid in the mixing an additive is commonly introduced as a compatibilizer. In this work, the effects various compatibilizers have on the mixing of polymer materials will be studied with the goal being to better understand the fundamental processes involved. As these effects are better understood, the knowledge can be applied to industrial systems with the aim of improving the processing and performance of polymer-based materials.