Study on surface hydrolytic kinetics of poly(vinyl acetate) grafted onto polyurethane film

Alkali catalytic hydrolysis of poly(vinyl acetate) (PVAc) grafting onto polyurethane film surface was a heterogeneous reaction. The hydrolysis was carried on the PVAc particle surface, and the concentration of the alkali in the system was tested by titration method. The kinetics of PVAc surface hydrolytic reaction was studied by simple second-order reaction model. From linear regression analysis of experimental data, we inferred that the activation energy (E _a ) and pre-exponential factor (A) of PVAc surface hydrolytic reaction were 70.7 ± 0.2 kJ mol^?1 and (5.7 ± 0.5) × 10¹² kg mol^?1 s^?1, respectively. The results of transmission electron microscopy stated that the apparent hydrolytic degree was 2.1% when the surface of PVAc particle hydrolyzed absolutely.