Synthesis, Structure and Properties of Hybrid Composite Bentonite-Based Materials

Abstract

A systematic study of the synthesis of hybrid composite materials based on synthetic (poly-Nvinylpyrrolidone) and natural (agar-agar) macromolecules in the presence of plasticizers (PEG-400, glycerin) and mineral filler bentonite has been performed by the method of electron irradiation. The methods of X-ray diffraction analysis and SEM show that the structure of the resulted hybrid compositions is defined as an interpenetrating network with the distributed intercalated particles of mineral component inside its volume. It has been established that mechanical properties of the hybrid composition are determined mainly by the structural organization of the interpenetrating polymer network, formed during electron irradiation of the initial polymer mixture in the presence of plasticizers, as well as by the conditions for intercalation of polymer segments into the interpacket layers of the mineral matrix. During the process of crazing the sample under tension the shear stress is concentrated in the central part of the sample from the periphery of the fastening. It is shown that the degree of swelling for hybrid composition strongly depends on the concentration of a low molecular plasticizer in the polymeric interpenetrating network, which can easily impregnate into the interplanar layers of bentonite.