Structural characteristics and state of water in an acetate cellulose membrane

Abstract

Experimental data have been obtained and an analysis has been performed of the degree of crystallinity and amorphism and the state of water for cellulose acetate membranes using the methods of X-ray diffraction (XRD), infrared spectroscopy and thermogravimetry. The degree of crystallinity, as well as the crystallite size, have been determined in the membrane samples before and after water absorption. It has been found that OH groups of cellulose acetate form a nonequilibrium network of hydrogen bonds between molecules and fragments in the amorphous phase of an air-dry semipermeable membrane. It has been shown that water that acts as a plasticizer causes the ordering of the macromolecular amorphous phase, which leads to a transition into the liquid crystal phase with the formation of additional capillary spaces.