Effects of thermal history on the peel strength of linear polyethylene

摘要

AbstractPeel strength of linear polyethylene–aluminum bonds is strongly affected by thermal history. Slow cooling from the melt resulted in 10 lb/in. peel strength; quenching, in 50–90 lb/in.; annealing of quenched bonds reduced the peel strength to 30 lb/in. Adhesion to aluminum was obtained by treating the substrates in a solution of vinyl triethoxysilane. Cohesive failure occurred regardless of thermal treatment. The changes in peel strength were not due to changes in strength of the bulk polymer. Rather, the volume of polymer deformed in peeling seemed to correlate with strength. No correlation was found between peel strength and degree of crystallinity or of transcrystalline orientation. Segregation resulting in a weak boundary layer seems to be the probable cause of the dependence of peel strength on cooling rate, and changes in the tie molecule configuration, the cause of loss of strength on anneal