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

Massachusetts Institute Of Technology, Cambridge MA

Investigators

Abstract

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.