CAREER: Synthesis, Characterization, and Application of Gel-Grown, Polymer-Reinforced Single Crystals

Cornell University, Ithaca NY

Investigators

Abstract

TECHNICAL SUMMARY: Recent observations, both in Nature and in the laboratory, of macroscopic, single crystals with incorporated polymer fibers and other macromolecules have generated immense interest amongst materials scientists, chemists, and biologists. The mechanisms by which they form, however, are poorly understood. The research goals of this CAREER proposal are: to understand the fundamental principles that govern the incorporation of polymer networks and macromolecules into single crystals, to develop synthetic routes to a wide range of polymer-reinforced crystals with detailed control over structure and porosity, to characterize the internal structure of these crystals, and to establish structure-mechanical property correlations for model systems. To accomplish these goals, the PI will develop the use of crystal growth in gels to produce polymer-reinforced single crystals of ionic, molecular, and covalent crystals. When successful, this work has the potential to transform our current understanding of the mechanisms that lead to the incorporation of large amounts of polymeric impurities within crystals, without disrupting their single crystal nature. The particular strength of this program lies in the interdisciplinary approach that combines the PI?s demonstrated expertise in crystal growth, organic synthesis, and materials characterization methods. By combining all of these efforts, the project aims to generate a fundamental understanding of the underlying mechanisms governing polymer fiber incorporation into single crystals. This understanding, in turn, will allow the PI to generalize the effects to materials of interest (e.g., bioactive minerals, inorganic semiconductors, pharmaceutical compounds). The ultimate goals of the project are to be able to design a gel system for a given crystalline material and to predict the growth conditions required to obtain single crystals of that material with incorporated networks. NON-TECHNICAL SUMMARY: This project aims to understand the mechanisms by which polymer networks become incorporated into macroscopic, single crystals. The ability to make a variety of single crystals that contain well-controlled distributions of organic polymers or pores, will lead to a new class of composite materials with interesting structure-property relationships and potential applications ranging from structural biomaterials to new formulations of pharmaceutical drugs to materials for energy generation and storage. The primary educational objectives of this CAREER proposal are to develop strategies for introducing students (K-12, undergraduates, and graduates) to the interdisciplinary fields of biological and bio-inspired materials, and in particular, to recruit more female students to the Materials Science and Engineering (MSE) department at Cornell University. The PI will train undergraduate and graduate students for future research jobs in materials science, with a focus on biomaterials. This preparation will include laboratory research as well as the development of two courses: ?Materials Chemistry? and ?Biomineralization?. The course on biomineralization will be integrated with the proposed research and is designed to train engineering students in the fundamentals necessary to design new biomaterials, based upon an understanding of the structure and formation of the natural biominerals (e.g., bone, teeth, shells). To impact recruitment and retention of women in MSE at Cornell, the PI will facilitate a new women?s group (Women in Materials Science and Engineering or WIMSE). The goals of this group are to foster a supportive community amongst women in the MSE department, to introduce female students to role models in industry and academia, and to increase the number of female undergraduate majors in MSE at Cornell over the next five years.