15:00 (online)
FAMU-FSU College of Engineering, Department of Chemical and Biomedical Engineering, Florida State University in Tallahassee, USA
Crystallization of Precision Polyethylene-Like Materials
Abstract:
Recent studies of polymorphism, melting behavior and crystallization kinetics of polyethylenes with moieties placed at an exact equal distance along the backbone will be presented with especial focus on the crystalline properties of precision polyethylenes with halogens, acetals and esters under rapid and isothermal crystallization from the melt. All display unusual discrete inversions in the temperature coefficient of the crystallization kinetics which correlate with transitions between crystalline structures differing in packing symmetry (polymorphs), or in a step-increase in crystal thickness. The origin of the rate minima will be discussed.