Properties and interfacial bonding for regenerated cellulose-polyurethane/amylase acetate SIPN composite films

Composite films were obtained by placing a polturethane/amylose acetate sem i-interpenetrating polymer network (SIPN) coating onto the surfaces of rege nerated cellulose (RC) film. The properties of the composite film, such as tensile strength, 79.9 MPa (in dnf state). 49.5 MPa (in wet stale), water r esistance (R), 0.62, dimensional stability (S-c). 3.0%. and water vapor per meability (P), 5.96 x 10(-5) kgm(-2)h(-1), are better than those of the unc oated RC film or RC film with PU coating, The interfacial strength was char acterized with infrared spectroscopy (IR), ultraviolet spectroscopy (UV), t ransmission electron microscopy (TEM), and electron probe microanalysis (EP MA). The results showed the existence of covalent and hydrogen bonds betwee n the SIPN coat laver and the RC laver. It was also found that the PU prepo lymer in the coating layer penetrated into the cellulose bulk, and reacted with the cellulose molecules. which formed another SIPN.