Irradiation of poly(vinyl ester)/clay nanocomposites

The effect of electron beam irradiation on pristine poly(vinyl ester) and cured poly(vinyl ester)/clay nanocomposite with different clay contents is studied at irradiation doses ranging from 100 to 1000kGy at room temperature. Poly(vinyl ester)/clay nanocomposites were prepared with different amounts of organically modified montmorillonite (1, 3, and 5wt.%) by in situ polymerization method. Morphology properties of synthesized nanocomposites were studied by X-ray diffraction and transition electron microscopy. The irradiation dose up to 500kGy yields an increase in Young's modulus and tensile strength of nanocomposites while further irradiation deteriorates the mechanical strength of samples. Irradiation has no considerable influence on the surface hardness of synthesized nanocomposites. Thermogravimetric analysis results reveal the thermal stability of poly(vinyl ester), and its nanocomposites is improved with irradiation up to 500kGy. However, similar to mechanical perdition at 1000kGy irradiation, thermal resistance of nanocomposites decreases. The enhancement in mechanical and thermal properties of synthesized nanocomposites is attributed to the cross-linking effect as bonds can be formed directly between the neighbouring chains.