APPLICATION OF THE RUBBER ELASTICITY THEORY TO THE CO-CROSS-LINKING OF ETHYLENE VINYL-ACETATE AND ETHYLENE METHYL ACRYLATE COPOLYMERS BY TRANSESTERIFICATION

The molten state transesterification reaction of ester groups of ethylene vinyl acetate copolymers and ethylene acrylic ester copolymers leads to a tetrafunctional network. The time and temperature dependence on the network formation is assessed. From the statistical theory developed by Flory on tetrafunctional crosslinking networks, and assuming a log normal distribution of the crosslinkable sites, the theoretical gel network formation is compared with the experimental data assessment of the gel fraction. A good agreement is then obtained between experimental and theoretical values.