Strain energy complexity in largely deformed poly (methyl methacrylate)
Yoshioka Shin'-ya; Matsumura Akihiko; Nanzai Yukuo
Abstract:Complexity of strain energy stored in largely deformed polymethyl methacrylate (PMMA) was studied through the tests of static strength and deformation recovery by heating the deformed samples. A relatively lower strain rate and higher temperature below the glass transition temperature at stretching of the PMMA samples to a strain of 0.10 lessened the ductility of the stretched samples. The long time stress relaxation at the fixed strain of 0.10 also lessened the ductility. On heating of the less ductile samples, their deformation recovery stimulated by internal strain energy stored in the samples commenced at temperatures much higher than those for the ductile samples. Thus, the ductility of the deformed PMMA samples was closely correlated with their deformation recovery behavior at heating. This correlation is probably associated with the inhomogeneous distribution of internal strain energy stored in the deformed polymer solid. Key Words:glassy polymer, large deformation, static fracture properties, deformation recovery at heating, strain energy