Synthesis and characterization of electrically conductive polyaniline/zeolite 13X nanocomposite and semi-interpenetrating polymer networks based on polyaniline and crosslinked polyvinylacetate.

摘要

Recent synthetic work at Albany by Dr. Frisch's group has focused on the development and characterization of polymer-based, novel, functional composite materials. These composites were prepared by synthesizing one component in the presence of the other. The resulting interpenetrated composites were further examined for their morphological characteristics, electrical and magnetic properties. Polyaniline salt/zeolite 13X composites and semi-IPNs based on polyaniline salt and crosslinked polyvinylacetate were synthesized and characterized.; Polyaniline/zeolite composites have been prepared by oxidative polymerization of aniline in the presence of zeolite 13X producing composite materials with polyaniline/zeolite weight ratios ranging from about 0.5 to 55. Our study showed that the D.C. conductivity of the composite materials decreased exponentially with zeolite weight fraction. Pure polyaniline was paramagnetic while the polyaniline/zeolite composites with weight ratios larger than 20 showed an appreciable antiferromagnetic component as indicated by temperature dependence of their electron spin resonance spectra. This novel antiferromagnetism is speculated to arise from π-dimer pairing of polyaniline chains absorbed on the zeolite particles.; Electrically conductive semi-IPNs based on polyaniline and crosslinked polyvinylacetate have been prepared by polymerization of aniline in the presence of crosslinked polyvinylacetate. Polyaniline successfully percolated through the crosslinked PVAc networks and the resulting semi-IPNs show a continuous network morphology. The conductivity of the semi-IPN increases with increasing content of polyaniline and increasing acidity used during the polymerization of the polyaniline. The D.C. conductivity of the semi-IPN is 0.13 S/cm with the highest polyaniline content of 19.3% (wt). The room temperature thermal mechanical strength from thermal mechanical analysis is largest for polyaniline followed by the semi-IPN of the polyaniline/crosslinked polyvinylacetate which is considerably stronger than the crosslinked polyvinylacetate.