Influence of thermal and mechanical histories on the viscoelastic behavior of drawn polyethylene

摘要

AbstractStorage and loss elasticity complex moduliE′ andE″ and temperatures at which the α relaxation takes place are studied with respect to thermal history, deformation speed, and molecular weight distribution of drawn linear polyethylene. Maximum values ofE′ andE″ increase with draw ratio of the hot‐drawn samples, and the α relaxation temperatures increase by around 10°C when the polyethylene filaments are annealed at 110°C. The activation energy of the process, considered as a single one because the symmetrical shape of the maxima, increases with draw ratio, and this increase is less pronounced when the filaments are annealed. Annealing of the filaments produces a decrease in theirE′ values, but this decrease is almost negligible for filaments obtained from polyethylene with a broad molecular weight distribution. The final crystallinity of the filaments drawn at room temperature and subsequently annealed is higher for the filaments obtained at lowe