CAREER: Reinforced Biopolymers for Nanocomposite Construction and Materials Science and Engineering Curriculum Development

在这项提议的职业奖研究工作中，生物聚合物，特别是多肽或可生物降解的聚酯，将被用作纳米复合材料（NC）结构的基质材料。 所提出的工作的智力价值是，通过使用生物聚合物作为基质材料，在聚合物纳米复合材料领域的重要基础和技术研究成果是可能的。 基础：A）人们可以通过多肽中可用的二级结构转变（例如无规卷曲到刚性杆a螺旋）来严格探索聚合物构象对纳米复合材料形成的影响。 B）可以可控地观察纳米级填料添加对聚合物基质材料的半结晶相行为的影响，这些影响将显著影响最终的NC性能。 因此，无论是构象对NC形成和增强相对聚合物结晶的影响将直接探讨。 技术：使用生物聚合物作为基质材料提供了将固有的生物性能（例如生物降解性、抗微生物活性）引入NC材料用于生物医学或环境友好用途的有趣的可能性。 这些材料的范围可以从可能的商品（抗菌包装）到专业/生物医学用途（坚韧，生物相容性植入材料）。知识价值延伸到纳米复合材料结构中所选的填料，因为传统和探索性增强材料也提供了基础和技术研究目标。 基础：使用二维片状填料和一维纤维状填料将提供两种几何形状作为适当NC增强材料的有效性的直接比较。 虽然已经进行了大量的工作2-D无机填料提供了丰富的文献结果与这些生物聚合物为基础的复合材料的结果进行比较，最近的调查碳纳米管在聚合物基体增强的功效也已经进行。 虽然本文所研究的血小板填料将是亲水和疏水改性的无机粘土材料，但原纤维增强将通过自组装的b-折叠肽原纤维来实现，所述b-折叠肽原纤维是传统上仅为生物科学界所熟悉的纳米结构。 技术：肽原纤维增强将提供产生刚性、坚韧、半结晶纳米复合材料的机会，由于增强相的固有肽化学，所述半结晶纳米复合材料潜在地100%生物相容性和生物可降解。 拟议工作的更广泛影响是由于拟议研究项目的跨学科性质，拟议的科学推广，以及将研究课题纳入拟议由PI开发的新课程。 这项工作的最重要的，更广泛的影响之一是跨学科的研究生谁将进行研究教育。 现代MSEG部门必须反映当前的跨学科研究范式和课堂环境中的主题材料，以适当地教育和培养学生感兴趣的材料。 为此，将开发一种新的先进的聚合物科学与工程课程，将Pochan实验室NC研究工作的物理性能评估结果与PI最近开发和教授的课程启发的课堂教学材料相结合。 这门新课程将是特拉华州大学（UD）MSE全体教师正在进行的积极努力的一部分，以设计和实施一个全新的21世纪世纪材料课程。

In this proposed Career award research effort, biopolymers, specifically polypeptides or biodegradable polyesters, will be used as the matrix materials for nanocomposite (NC) construction. The intellectual merit of the proposed work is that both significant fundamental and technological research accomplishments in the area of polymer nanocomposite materials are possible by using biopolymers as matrix materials. Fundamental: A) One can rigorously explore the effect of polymer conformation on nanocomposite formation through secondary structure transitions available in polypeptides (e.g. random coil to rigid-rod a helix). B) One can controllably observe the effects of nanoscopic filler addition on the semi-crystalline phase behavior of polymer matrix material, effects that will significantly affect the ultimate NC properties. Therefore, both conformation effects on NC formation and reinforcement phase effects on polymer crystallization will be directly probed. Technological: the use of biopolymers as the matrix material offers the intriguing possibility of introducing inherent biological properties (e.g. biodegradability, antimicrobial activity) into the NC material for biomedical or environmentally benign uses. These materials could range from possible commodity (antimicrobial packaging) to specialty/biomedical uses (tough, biocompatible implant materials).The intellectual merit extends to the chosen filler for nanocomposite construction in that traditional and exploratory reinforcement materials also provide both fundamental and technological research goals. Fundamental: the use of both 2-dimensional platelet vs. 1-dimensional fibrillar fillers will provide a direct comparison of the effectiveness of the two geometries as adequate NC reinforcement material. While significant work has been performed on 2-d inorganic fillers providing a wealth of literature results with which to compare these biopolymer-based composite results, more recently investigations into the efficacy of carbon nanotubes in polymer matrix reinforcement have also been performed. While the platelet filler to be studied herein will be inorganic clay materials, both hydrophilic and hydrophobically modified, the fibrillar reinforcement will be accomplished by self-assembled b-sheet peptide fibrils, a nanostructure traditionally familiar only to the biological science community. Technological: Peptide fibril reinforcement will provide the opportunity to produce stiff, tough, semicrystalline nanocomposites that are potentially 100% biocompatible and biodegradable due to the inherent peptide chemistry of the reinforcement phase. The broader impacts of the proposed work are due to the interdisciplinary nature of the proposed research project, the proposed scientific outreach, and the integration of research topics into new courses proposed to be developed by the PI. One of the most important, broader impacts of this proposed work is the interdisciplinary research education of the graduate students who will perform the research. A modern MSEG department must reflect current interdisciplinary research paradigms and topical material in the classroom environment in order to properly educate and train students interested in materials. Towards this end, a new, advanced polymer science and engineering course will be developed that integrates the physical property assessment results from the Pochan lab NC research effort with classroom lecture material inspired by courses recently developed and taught by the PI. This new course would be part of an ongoing, aggressive effort by the entire faculty in MSE at the University of Delaware (UD) to design and implement a totally new, 21st century materials curriculum.