Preparation of polyaniline nanomatrix formed in natural rubber

Natural rubber-grafted polyaniline with a nanomatrix structure was prepared and characterized. The graft copolymerization of aniline on natural rubber was performed in the latex stage. Factorial experimental design and univariate experiments were used to evaluate the effect of the factors on the conversion of aniline in the graft copolymerization. The structure of the products was characterized through 1H-NMR spectroscopy. The thermal properties, electrical conductivity, and morphology of the products were investigated. The results from the factorial experimental design showed that reaction temperature was the most important factor affecting the conversion, pH was the next most important, and the other factors were relatively unimportant. Polyaniline was confirmed to graft onto natural rubber and form a nanomatrix structure in the resulting material. The thermal properties and electrical conductivity of natural rubber-grafted polyaniline with a nanomatrix structure were improved compared to those of a polyaniline/natural rubber blend with an island-matrix structure. Natural rubber-grafted-polyaniline with nanomatrix structure was prepared through graft-copolymerization. The effect of parameters on the graft-copolymerization was investigated using factorial experimental design and univariate experiments. The structural characterization of the resulting materials through NMR spectroscopy confirmed that aniline was grafted on the natural rubber. As observed in TEM image, polyaniline, which covered the natural rubber particles, formed the nanomatrix, and natural rubber particles formed the dispersed phase. The thermal properties and electrical conductivity of natural rubber-grafted-polyaniline were improved by the formation of nanomatrix structure.