Polymer processing and characterization: microstructure development and control in polymer micro- and nano-processing

在接下来的五年里，我们将利用我们在聚合物加工和表征领域的知识基础和经验，特别是在微观结构发展的预测和控制方面，为现有产品问题提供解决方案，或促进具有实质性附加值的新产品的开发。在纳米复合材料方面，我们将继续研究聚丙烯和苯乙烯，包括共聚物（如ABS）。有机粘土的热稳定性和表面能特性将得到改善和优化。我们在聚（对苯二甲酸乙二醇酯）纳米复合材料的熔融加工方面的工作将继续努力开发一种用于生产剥离结构的改进工艺，同时保持聚合物的高分子量。一个新的突破点是开发基于聚乳酸（PLA）与其他可生物降解共聚物的共混物的吹塑制品，以弥补PLA熔体强度的不足。不同于粘土的纳米颗粒将被考虑用于某些应用，特别是纳米晶体纤维素（NCC）。我们将扩展我们的注射成型模拟软件来处理微注射成型。通过操纵形态，我们将试图消除微模塑件中的弱点，并生产出具有与常规宏观模塑件相当强度的微模塑件。一些纳米复合材料将被考虑用于微成型，并且将评估和操纵激光焊接对接头的微观结构和强度的影响。 压力辅助微成型将用于复制表面微特征。我们将利用我们在压力、静态和剪切条件下等温和非等温聚合物结晶方面的丰富经验，提高激光和振动焊接热塑性接头的强度。 同样，我们将调整我们的薄膜吹塑模型，以控制在聚烯烃薄膜形成过程中的微观结构，通过拉伸和退火的吹塑聚烯烃薄膜。

During the next five years, we shall build upon the strength of our knowledge base and experience in the polymer processing and characterization field, particularly regarding the prediction and control of microstructure development to provide solutions to existing product problems or to facilitate the development of new products with substantial added value. In nanocomposites,we shall continue work on polypropylene and styrenics, including copolymers (e.g. ABS). Thermal stability and surface energy characteristics of organoclays will be improved and optimized. Our work on melt processing of poly(ethylene terephthalate) nanocomposites will continue efforts to develop an improved process for production of exfoliated structure, while maintaining polymer high molecular weight. A new thrust in involves the development of blow molded articles based on blends conaining poly(lactic acid) (PLA) with other biodegradable copolymers, to compensate for the lack of melt strength of PLA. Nanoparticles different from clay will be considered for some applications, particularly nanocrystalline cellulose (NCC). We shall extend our injection molding simulation software to deal with micro injection molding. By manipulating morphology, we shall attempt to eliminate weak points in micro-moldings and to produce micro-moldings with comparable strength to conventional macro-moldings . Some nanocomposites will be considered for micromolding, and the effect of laser welding on the microstructure and the strength of the joint will be evaluated and manipulated. Pressure-assisted micro molding will be used to replicate surface microfeatures. We shall use our extensive experience in isothermal and nono-isothermal polymer crystallization under pressure and under quiescent and shear conditions to improve the strength of laser and vibration welded thermoplastic joints. Similarly, we shall adapt our film blowing models to the control of microstructure during the formation of polyolefin membranes by stretching and annealing of blown polyolefin films.