An Integrated Laboratory Approach toward the Preparation of Conductive Poly(phenylenevinylene) Polymers

摘要

Poly(phenylene vinylene) (PPV) represents an important class of conjugated, conducting polymers that have been readily exploited in the preparation of organic electronic materials. In this experiment, students prepare a PPV polymer via a facile multistep synthetic sequence with robust spectroscopic evaluation of synthetic intermediates and the final product. The synthetic sequence could be applied by university instructors as a capstone project for an undergraduate organic chemistry laboratory or as a centerpiece project for either a polymer or integrated laboratory course. The initial synthetic step could be segmented and used as a modular piece in the traditional introductory organic chemistry laboratory. In either case, the resultant PPV polymer is analyzed by UV-vis and fluorescence spectroscopy to determine the quantum yield which promotes enhanced student understanding of the photophysical properties of the material. In addition, GPC analysis is completed to reveal the molecular weight and polydispersity of the polymer. Students completing this experiment gain valuable experience in organic/polymer synthesis and structural characterization utilizing GC/MS, GPC, NMR, UV-vis, and fluorescence spectroscopy, as well as in the mechanistic aspects and practical application of some of the classic transformations in organic chemistry including the S(N)2 reaction, nucleophilic acyl substitution, organometallic chemistry, and Wittig reaction.