Effect of Particle Additives on Grain Boundary Formation in Block Copolymer Thermoplastic Elastomers

本研究的目的是进一步了解链结构和纳米级颗粒添加剂对嵌段共聚物/纳米颗粒共混物中有序机制和平衡微观结构形成以及晶界结构稳定的影响。在第一部分中，该计划将重点研究长时间退火后静态有组织嵌段共聚物-纳米颗粒共混物的结构形成，以确定共聚物链结构对平衡复合结构的影响，并阐明纳米添加剂存在时晶界结构的形态。在第二部分，结合光学和电子显微镜的研究将集中在区域微观结构的成核和生长，特别是在晶界区域的粒子聚集对单个共聚物晶粒生长动力学的影响。一个互补的合作项目将阐明杂化嵌段共聚物微观结构的晶界形成“后组织”的含义，通过从定向嵌段共聚物/纳米颗粒复合材料的模型晶界结构工程和随后的时间分辨分析颗粒分布对平衡形态扰动的响应。对纳米结构多相材料的认识是实现突破性技术进步的支柱之一。在其“纳米材料研发路线图”中，几家领先的化学公司的合作伙伴关系确定了多相纳米材料的开发，利用其成分之间的协同作用，将在未来的技术支持过程中发挥关键作用。提出的研究计划将促进我们对嵌段共聚物/纳米颗粒共混物的结构形成的理解，这将有利于未来高性能聚合物复合材料和嵌段共聚物基热塑性弹性体经济相关领域的发展。该项目将为聚合物和纳米材料关键领域的一名研究生和几名本科生提供培训，这些领域已被美国国家科学院和工程院确定为确保美国未来创新和经济实力的关键战略相关性。与拜耳材料科学研究中心的合作将促进商业相关成果的识别和开发，并为学生创造一个激励人心的工作环境。

TECHNICAL SUMMARYThe objective of the proposed research program is to further our understanding of the implications of chain architecture and nanoscale particle additives on the ordering mechanism and equilibrium microstructure formation as well as the stabilization of grain boundary structures in block copolymer/nanoparticle blends. In a first part, the program will focus on the structure formation in quiescent organized block copolymer-nanoparticle blends after long-time annealing in order to establish the effect of the copolymer chain architecture on the equilibrium composite microstructure as well as to elucidate the morphology of grain boundary structures in the presence of nano-additives. In a second part, a combined optical and electron microscopy study will focus on the nucleation and growth of the domain microstructure and in particular on the implications of particle aggregation in grain boundary regions on the growth kinetics of individual copolymer grains. A complementary collaborative project will elucidate the implications of grain boundary formation 'post-organization' of the hybrid block copolymer microstructure, by engineering of model grain boundary structures from oriented block copolymer/nanoparticle composite materials and subsequent time-resolved analysis of the response of the particle distribution to the perturbation of the equilibrium morphology.NON-TECHNICAL SUMMARYThe understanding of nanostructured multiphase materials is considered as one of the pillars for realizing breakthrough technological progress. In its 'R&D Roadmap for Nanomaterials' a partnership of several leading chemical companies ascertains that the development of multiphase nanomaterials that capitalize on the synergism between their constituents will play key role in future technology-enabling processes. The proposed research program will advance our understanding of the structure formation in block copolymer/nanoparticle blends that will be beneficial to the development of future high performance polymer composite materials and the economically relevant field of block copolymer-based thermoplastic elastomers. The program will provide training for one graduate and several undergraduate researchers in the critical area of polymer and nanoscale materials that has been identified by the National Academies of Science and Engineering as being of key strategic relevance for securing the future innovativeness and economic strength of the US. Collaboration with the BAYER MaterialScience research center will promote the identification and exploitation of commercially relevant results and contribute to a stimulating work-environment for students.