Self-Assembling Polymers: Synthesis and Characterization

University Of Wyoming, Laramie WY

Investigators

Abstract

Self-Assembling Polymers: Synthesis and Characterization Project Summary Shen / Wyoming / 0650608 Bioinspired synthetic nano-scale macromolecules capable of hydrogen (H)-bonding-mediated self-assembly into well-defined 3D-structures with tailored properties and functions is a grand challenge in polymer science and engineering. Such supra-molecular assembly of macromolecules via specific intermolecular interactions requires a uniform chain length and a controlled sequence of H-bonding sites. Current living polymerization of vinyl monomers can produce polymers of controlled chain lengths, but cannot control the chain composition and sequence. The goal of this research, therefore, is to synthesize length- and sequence- specific self-assembling polymers and characterize their self-assembly properties. A novel templated-living radical polymerization (TLRP) using living radical polymerization to control the chain lengths and using a template to direct the monomer distribution and sequence will be used to synthesize such polymers. The template and its daughter chain have complementary H-bonding sites and thus are expected to self-assemble into 3D-structures such as highly aligned duplexes, reminiscent of DNA hybridization. Specific aims of the proposed research are to (1) design and synthesize self-assembling monomers and templates; (2) optimize living radical polymerization conditions for these monomers aimed at uniform chains and low polydispersity; (3) define conditions for the templated-living radical polymerization process; and (4) separate the template and its daughter chain and characterize their self-assembling properties. In preparation of this proposal, critical concepts have been demonstrated to confirm the feasibility of the proposed research. Living radical polymerization of sample monomers has been conducted. The preferable self-assembly of the monomers with the complementary polymer chains to the monomers, which is the prerequisite for the proposed TLRP, has also been demonstrated. Intellectual Merit: Synthesis of nan0-scale macromolecules capable of self-assembly into controlled supramolecular structures is a great challenge. This project will produce a templated-living radical polymerization for vinyl monomers to synthesize such self-assembling vinyl polymers. This study will lead to a fundamental understanding of the templated-polymerization and self-assembly of polymers, and provide guidance for our long-term goal of using peptide nucleic acid or oligonucleotides as templates. Broad Impact: The project includes strong societal and educational components. The proposed research will develop a new approach to synthesize new functional polymer materials. These materials have many such potential applications as antisense medicines and biosensors, and new silk-like materials having exceptional mechanical and thermal properties. In conjunction with this research, the education goal of this project is to educate and train a new generation of skilled worker force and attract students to science and engineering. Thus, the education activities will involve students at all levels (college and precollege). The PI will include more students at all levels and particularly minority and women students involved in the research via (1) reaching out to precollege students, particularly underrepresented American Indians through the university's Multicultural Affairs Summer Research Apprentice Program, and (2) providing research opportunities to undergraduates via the summer scholarship program and the University's Research Experience Program. The PI will also integrate the results from this research, particularly the synthesis of bioinspired materials into his chemical engineering curricula. Particularly, the PI will create a Polymer Lab for his CHE 5190/4190 and CHE 5170/4170 offered to campus-wide graduate and undergraduate students to give the students hands-on experience in polymer synthesis, characterization and applications. Thus, this project will allow the PI to reach out and educate students at all levels, have them involved in the research, and align undergraduate education with research and graduate training programs. This will provide experiences that would help students to make connections and transfer concepts across spheres of knowledge and would stimulate and excite students engaged in science and engineering.