Frontal polymerization in microgravity - Results from the Conquest I sounding rocket flight
Polymers and High Performance Materials
Frontal polymerization is a mode of converting monomer into polymer via a localized reaction zone that propagates, most often through the coupling of thermal diffusion and Arrhenius reaction kinetics. Because of convection instabilities, it is not possible to perform frontal polymerization with many monomers that produce thermoplastics, such as n-butyl acrylate, without the addition of a viscosity enhancing agent. Performing propagating fronts of n-butyl acrylate polymerization on the Conquest I sounding rocket allowed us to determine that the ultrafine silica gel (CAB-I-SIL) used in ground based research had only a small effect on the molecular weight of the polymer produced. Samples prepared with CAB-O-SIL did have slightly broader molecular weight distributions that could reflect the decrease in termination because of the higher viscosity. However, the difference could also be caused by differences in front temperature because of the lack of convective heat losses under weightlessness.
MICROGRAVITY SCIENCE AND TECHNOLOGY
Mathias, L. J.
(1997). Frontal polymerization in microgravity - Results from the Conquest I sounding rocket flight. MICROGRAVITY SCIENCE AND TECHNOLOGY, 10(1), 36-40.
Available at: http://aquila.usm.edu/fac_pubs/5455