Frontal Polymerization (FP) is a process in which a spatially localized rea
ction zone propagates into a monomer converting it into a polymer. Two type
s of frontal polymerization processes have been observed experimentally. On
e is exothermic FP, which occurs due to diffusion of heat released in the p
olymerization reactions and which we have previously studied. The other is
an isothermal FP process, also referred to its interfacial gel polymerizati
on, which is due to mass diffusion of the species coupled with the gel effe
ct. We propose and study a model of interfacial gel polymerization. We dete
rmine, both numerically and analytically, important characteristics of the
process including the time-dependent propagation velocity of the reaction z
one, the structure of the wave, and the distance traveled by the front befo
re it breaks down due to reactions ahead of the front. (C) 1999 Elsevier Sc
ience Ltd. All rights reserved.