DMREF/GOALI: Discovery and Design of Additives for Novel Polymer Morphology and Performance

聚乙烯和聚丙烯等塑料由于其独特的加工性、机械、热学、光学甚至电子性能组合，构成了先进材料市场中一个重要且日益多样化的领域。从历史上看，这些材料是在几十年的时间里开发和改进的，主要是通过耗时的经验方法。在当今世界，全球竞争力取决于新材料发现和开发的较短开发周期。例如，设计添加剂以生产比目前可用的更坚硬和更坚韧的轻质塑料，将有利于社会和经济对能源和材料节约的要求。考虑到这些因素，DMREF学术与工业联系机会(GOALI)项目旨在通过快速评估改变最终产品结构和性能的添加剂来加速先进塑料的发展。它通过使用高性能计算的高通量筛选的迭代过程来做到这一点，并有针对性地对“同类最佳”候选人进行实验。这种方法代表了一种新的范式，可以促进美国的竞争力和创新实践，进而转化为美国制造业经济中的就业创造。与业界在该项目上的合作提供了一种实现这些好处的机制。该项目通过工程师和科学家的教育和专业发展，以及通过将成功的做法传播到先进材料发现的其他领域，进一步服务于社会。该项目设想的材料发现新范式是基于(I)分子水平模拟、(Ii)实验验证、(Iii)材料设计和优化以及(Iv)工业应用的协同应用，以确定分子结构、形态和性能之间的本质关系。在该计划中，这一范例是通过发现和设计添加剂(成核剂、澄清剂、纳米膜等)实现的。这改变了聚烯烃的半结晶形态，从而也改变了它们的性质。分子模拟被用来对添加剂类进行广泛的筛选，然后在选定的情况下使用一种测量非均相成核动力学的新技术进行实验验证。进化策略和相关方法被用于在添加剂类内和跨添加剂类设计和优化候选化合物，以便随后在工业合作者的实验室内进行合成、开发和表征。该项目促进了关于如何通过合理设计可操纵结晶动力学和半结晶形态的添加剂来改变聚烯烃的性质和性能的科学和技术知识。它产生了新的理论和计算方法，不仅可以预测成核动力学，而且还可以深入了解成核机理。

Plastics like polyethylene and polypropylene constitute an important and increasingly diverse sector of the advanced materials market, due to their unique combinations of processability, mechanical, thermal, optical and even electronic properties. Historically, these materials have been developed and refined over many decades, largely through time-consuming empirical methods. In today's world, global competitiveness depends on shorter development cycles for the discovery and development of new materials. For example, the design of additives to produce lightweight plastics that are stiffer and tougher than those currently available would benefit societal and economic requirements for energy and material conservation. With these things in mind, this Designing Materials to Revolutionize and Engineer our Future (DMREF) Grant Opportunities for Academic Liaison with Industry (GOALI) project seeks to accelerate the development of advanced plastics through the rapid evaluation of additives that change the structure, and therefor the properties, of the final product. It does so through an iterative process of high throughput screening using high performance computing, and targeted experimentation with "best in class" candidates. This approach represents a new paradigm that can contribute to US competitiveness and innovative practices, which in turn translate into job creation within the US manufacturing economy. Collaboration with industry on this project provides a mechanism to realize these benefits. This project further serves society through the education and professional development of engineers and scientists, and through propagation of successful practices into other areas of advanced materials discovery. The new paradigm for materials discovery envisioned for this project is based on the synergistic application of (i) molecular level simulation, (ii) experimental validation, (iii) materials design and optimization, and (iv) industrial application, to identify essential relationships between molecular structure, morphology and performance. In the program, this paradigm is realized through the discovery and design of additives (nucleating agents, clarifiers, nanofillers, etc.) that alter the semicrystalline morphology of polyolefins, and thereby their properties as well. Molecular simulations are used to conduct broad screenings of additive classes and then validated experimentally in select cases using a new technique to measure heterogeneous nucleation kinetics. Evolutionary strategies and related methods are used to design and optimize candidates within and across additive classes, for subsequent synthesis, development and characterization within the laboratories of the industrial collaborator. This project advances scientific and technical knowledge regarding how the properties and performance of polyolefins can be transformed through rational design of additives that can manipulate crystallization kinetics and semicrystalline morphology. It results in new theoretical and computational methods that not only predict nucleation kinetics, but also provide insight into nucleation mechanisms.