Behavior in frontal polymerization

J. Masere, F. Stewart, T. Meehan, and J. Pojman, Period-doubling behavior in frontal polymerization of multifunctional acrylates. Chaos, 9 (1999), pp. 315-322. 

Ainsworth, W. Pojman, J. A. Chekanov, Y. Masere, J. Bubble Behavior in Frontal Polymerization Results from KC-135 Parabolic Flights in Polymer Research in Microgravity Polymerization and Processing ACS Symposium Series No. 793 Downey, J. P. Pojman, J. A., Ed. American Chemical Society Washington, DC, 2001 pp 112-125. 

Bubble Behavior in Frontal Polymerization Results from KC-135 Parabolic Flights... 

Pojman, J. Volpert, V. Dumont, T. Ainsworth, W. Chekanov, Y. Masere, J. Wilke, H. Bubble Behavior and Convection in Frontal Polymerization on the KC-135 Aircraft, AlAA 2000-0856, 38th Aerospace Sciences Meeting, 2000. 

Diffusion of small molecules, usually solvents, into glassy polymers exhibits anomalous or non-Fickian behavior 34). As the solvent penetrates, the diffusion coefficient increases because the glass transition temperature is lowered. The solvent acts as a plasticizer, increasing the free volume and the mobility of the solvent. Thus we have an autocatalytic diffusion process. This can be relevant in Isothermal Frontal Polymerization, which we discuss below. 

Frontal polymerization discovered in 1972 (5) could be realized in free-radical polymerization because of its nonlinear behavior. If the top of a mixture of monomer and initiator in a tube is attached to an external heat source, die initiators are locally decomposed to generate radicals. The polymerization locally initiated is autoaccelerated by the c(xnbinatithermal autocatalysis exclusively at the top of the reaction systmn. An interface between reacted and unreacted regions, called propagating front, is thus formed. Pojman et al. extensively studied the dynamics of frontal polymerization (d-P) and its applicatim in matoials syndiesis (I -I3). 

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