TEARING RESISTANCE OF MULTILAYER PLASTIC FILMS

The tear resistance of multi-layered plastic films can be generally pr edicted from the tear resistance of individual layers by an additive r ule. The most notable exception from this additive rule is the case of multi-layered films containing a polyethylene layer. The reason for t his specific case is explained by the constraint on the plastic yield zone of polyethylene, which causes a dramatic drop in the tear resista nce of the multi-layered film. An extensive plastic zone is generated during the tear fracture of a single layer polyethylene film. This yie ld zone does not appear when polyethylene is laminated with other poly mer firms.