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 ethyl ene vinyl acetate copolymers and ethylene acrylic ester copolymers lea ds to a tetrafunctional network. The time and temperature dependence o n the network formation is assessed. From the statistical theory devel oped by Flory on tetrafunctional crosslinking networks, and assuming a log normal distribution of the crosslinkable sites, the theoretical g el network formation is compared with the experimental data assessment of the gel fraction. A good agreement is then obtained between experi mental and theoretical values.