Non-isothermal fusion bonding of polypropylene

The fusion bonding of neat polypropylene (PP) has been investigated under n on-isothermal conditions with different initial adherend temperatures, and the results compared with results from bonds prepared under isothermal cond itions with identical adherend temperatures. The mode I critical strain ene rgy release rate of the bonds, G,, was measured using a double cantilever b eam geometry with a constant crack opening displacement. The effect of the adherend temperature and the hold time are summarized in time-temperature a nd fracture energy-temperature maps, a methodology that is easily applicabl e to other systems. Of immediate practical interest is the observation that for estimated interface temperatures just above the melting point, non-iso thermal bonding gave bonds with G, approaching that of the bulk resin after much shorter times than isothermal bonding. (C) 2001 Elsevier Science Ltd. All rights reserved.