Investigations for obtaining semi-interpenetrating polymer networks based on monomers of different reactivity toward radicals

Classically, the one‐step synthesis of interpenetrating polymer networks (IPNs) and related materials requires noninterfering polymerization modes to achieve distinct networks, held together by only physical entanglements. For the combination of (meth) acrylic and allylic monomers, both polymerizable by free radicals, a new in situ sequential synthesis for obtaining semi‐IPNs is proposed. Using specific initiators that decompose at two different temperatures, refractive index measurements, Fourier transform infrared spectroscopy, and dynamic mechanical analysis have shown that neat species are formed and that the two monomers do not copolymerize. © 1993 John Wiley & Sons, Inc.