Preparation of Tailored Length Thiophene Benzobisthiazole Oligomers with Solubilizing Decyloxy Pendants for Third Order Nonlinear Optical Property Correlations.

摘要

In an effort to better understand the relationship between molecular weight and third-order nonlinear optical (NLO) activity for condensation polymers, a series of thiophene containing benzobisthiazoles were synthesized via a trimethylsilylpolyphosphate (PPSE) catalysed condensation of a bis-o-aminothiophenol monomer and a didecyloxythiophene dicarboxylic acid. The physical and chemical characterization of these oligomers, including molecular weight determinations, are summarized. The enhancement of the bulk susceptibility and second molecular hyperpolarizability are demonstrated to increase with increasing oligomer length. Based on the data from femtosecond degenerate four-wave mixing (DFWM) experiments, the second hyperpolarizability of the oligomers is enhanced by two-photon resonance.... condensation polymers, third order bulk susceptibility, second molecular hyperpolarizability two photon resonance, degenerate four-wave mixing, nonlinear optical materials.