The first synthesis of a polyurethane by frontal polymerization has been successfully carried out. Namely, the two reactants (1,6-hexamethylene diisocyanate and ethylene glycol) and the catalyst (dibutyltin dilaurate) were mixed together at room temperature in the presence of an additive (pyrocatechol, necessary for extending pot life), dimethyl sulfoxide (as the solvent), and a filler (fumed silica, added for stabilizing the propagating front). The reactions were thermally ignited at one end of the tubular reactor, and the resultant hot fronts were allowed to self-propagate throughout the reaction vessel. The effects of relative amounts of the above components on the most relevant parameters relating to frontal polymerization (temperature profile, front velocity, and temperature) were thoroughly investigated.

Anionic poly ( -caprolactam), isothermally synthesized at temperatures between 155 and 195 °C by very fast carbamoyl-type activators, has been characterized by UV, DSC, and wide-angle X-ray scattering (WAXS) techniques in terms of high polymer yield, irregular structures along the chain, extent of cross-linking, Tg and Tm values, degree of crystallinity, and polymorphism. The specific role of four different activators on the above properties has been compared. From the whole set of characterization data it is evident that cyclohexylcarbamoylcaprolactam behaves as the most suitable activator and provides poly( -caprolactam) with properties that favorably match those of the corresponding hydrolytic polyamide.

Interpenetrating polymer networks made of dicyclopentadiene and methyl methacrylate or tri(ethylene glycol) dimethacrylate have been successfully prepared by non-interfering frontal polymerization. The role of catalyst and free radical initiator relative amounts, as well as of monomer ratio, has been thoroughly studied. The conditions under which a pure frontal polymerization occurs, and the related values of both front velocity and maximum temperature reached by the reaction, are presented and discussed.

The frontal polymerization technique has been successfully applied, for the first time, to obtain an unsaturated polyester/styrene resin. The effect of the ratio of the two aforementioned components, as well as of the type and amount of free-radical initiator on both front velocity and maximum temperature reached by the front, has been thoroughly studied. The resulting products have been characterized in terms of their thermal and dynamic-mechanical behaviour. A comparison of such products with the corresponding materials obtained by the classical batch polymerization technique has evidenced that frontal polymerization allows to reach a higher degree of crosslinking with respect to batch copolymerization and hence a better thermal and mechanical behaviour.

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