Convective instabilities in traveling fronts of addition polymerization
Traveling fronts of polymerization have been observed in unstirred solutions of methacrylic acid and peroxides or nitriles. Four types of convective instabilities have been observed. 1) The heat released by the exothermic reaction decreases the density of the reacting solution but changes in the composition tend to make the density increase. 2) However under some conditions of concentration of temperature, long slender 'fingers' of polymer are observed to sink from the solid polymer front. 3) Pulsating fronts have been observed that result in a striated material. 4) Spinning modes of front propagation have been observed in adiabatic systems. Convection may be the dominant destabilizing mechanism for these last two phenomena so microgravity experiments are proposed to investigate them.
Publication Source (Journal or Book title)
American Society of Mechanical Engineers, Applied Mechanics Division, AMD
Pojman, J. (1993). Convective instabilities in traveling fronts of addition polymerization. American Society of Mechanical Engineers, Applied Mechanics Division, AMD, 174, 105-117. Retrieved from https://digitalcommons.lsu.edu/chemistry_pubs/1281