ABSTRACT
The activated anionic polymerization of ε-caprolactam in presence of butadiene-acrylonitrile elastomers has been extensively studied. The classical, relatively slow activators lead to monomer conversion and polymerization rates that are, to some extent, reduced in comparison to polymer formation from the neat monomer. Moreover, the polymerization kinetics is dramatically affected by the degree of mixing of the reactants containing the catalytic species, the monomer and the rubber, as well as the contact time between the basic initiator and the rubber.
Very fast polymerization activators minimize the retardation effects of the rubber, thus suggesting possible developments of the polymerization process in terms of RIM technology. By suitably changing the experimental procedures it is possible to induce controlled crosslinking and degradation of the rubber, which represent essential prerequisites in order to obtain high monomer conversions as well as peculiar morphologies of the multiphase polymer system. Molecular characteristics and morphologies of the polymerization products have been correlated to the most relevant reaction parameters.
