Synthesis and characterization of novel multifunctional polymers based on 1,6-Heptadiyne derivatives

Abstract

Part Ⅰ. Poly(1,6-heptadiyne) Derivatives for Photonic Application. A new class of multifunctional polymers based on poly(1,6-heptadiyne) derivatives have been synthesized by metathesis cyclopolymerization. Firstly, new photorefractive polymers based on the work for the photoconductivity and electro-optic activity of poly(1,6-heptadiyne) derivatives containing a carbazole moiety or NLO chromophores. Herein, all functional groups are covalently linked to the polymer backbone to overcome some problems such as phase separation and instability of electro-optic activities, etc.. The resulting polymers were obtained from the copolymerization of 1,6-heptadiyne derivatives containing several chromophores in various monomer feed ratio. The molecular weights of the resulting polymers were estimated by gel-permeation chromatography (GPC) to be in the range $Mn=2.3×10^4$ to $4.5×10^4$ and the polydispersities were in the range of 2.1-3.1. The mole ratios of the resulting copolymers were determined by $^1H$-NMR analysis. All the copolymers were polymerized nearly quantitatively as a monomer feed. And all copolymers of various mole ratios was relatively well soluble in common organic solvents and were easily cast on ITO glass plate or quartz plate to give violet, shiny thin films. Furthermore, all polymers were amorphous. Secondly, we have described new conjugated poly(1,6-heptadiyne) derivatives with various substituents such as fluorinated alkyl, carbazole, and silicon-containing pendant groups for the third-order optical nonlinearity of these polymers via metathesis cyclopolymerization. The third-order optical nonlinearity of these polymers for photonic applications were investigated by degenerate four-wave mixing method. These polymers were of quite high molecular weight ($~10^5$) and were highly soluble in common organic solvents. The third-order nonlinear optical coefficient, $X^{(3)}$, of the resulting polymers were found to be 0.44 to $4.1× 10^{-11}$ esu. Esepecially...