RUI: Thermal and Opto-rheological Studies of Poly(p-phenylene vinylene) (PPV) and PPV Derivatives

Rutgers University New Brunswick, New Brunswick NJ

Investigators

Abstract

Poly(p-phenylene vinylene)(PPV) and PPV derivatives are of interest for their potential in a variety of electronic and optical device applications. Because the final PPV polymer is highly conjugated and insoluble, the preferred synthetic method follows a precursor polymer route. The routes are referred to as: sulfonium precursor route (SPR), xanthate precursor route (XPR) and chlorine precursor route (CPR). In this project, PPV and PPV derivatives will be synthesized via each of these routes depending on the desired product. PPV will be synthesized from the xanthate precursor which results in a more amorphous polymer. The thermal elimination reaction mechanism and the kinetics of the reaction will be analyzed. This will provide the half-life (shelf-life) of the precursor which is important for commercial application of the polymer. A full understanding of the thermal elimination reaction is important because the conditions of the thermal elimination reaction influence the properties of the final product. Other PPV derivatives that will be synthesized include, for example: poly(2,5-dimethoxy-p-phenylene vinylene)(DM-PPV); poly(phenoxyphenylene vinylene)(PO-PPV) and poly(2,3 diphenyl phenylene vinylene)(DP-PPV). Their thermal properties will be analyzed as discussed above for the xanthate precursor. In addition, the opto-rheological technique that will be employed is referred to as dynamic infrared linear dichroism (DIRLD) and has only recently been applied to the analysis of electroactive polymers. This study will relate the molecular motions (vibrational modes in the infrared region) to the bulk macroscopic properties observed by dynamic mechanical analysis (DMA). %%% Students will be actively engaged in materials research from the synthesis of the polymer precursor through to characterization by thermal analysis and DIRLD. Undergraduate students will work with a graduate student and the PI. Results will be discussed at weekly group meetings where ideas can be exchanged and questions answered. The research will be formally presented at the local, regional and national levels with publications submitted to referred journals for dissemination to the materials science community.