Abstract
Effect of heat treated oil, existing on the surface of aluminum, on the adhesion of polyethylene to aluminum was investigated. The results obtained are as follows:
(1) The oil on the aluminum surface was removed abruptly when it was heated at 200°C for 5hrs or at 300°C for 5hrs.However, complete oil removal was possibly by heating at 400°C for more than 5hrs.
(2) The peeling strength of aluminum, covered by oil was decreased monotonously with the heat treatment, while that of aluminum covered by oil was decreased in an irregular manner with the heat treatment. The decreasing rate of the peeling strength was slower in the case of aluminum covered by oil.
(3) Aluminum surfaces contaminated by polar oleic acid or butylstcarate had a larger peeling strength and showed slower decrease of the strength upon heat treatment than those contaminated by non-polar liquid paraffin.
(4) In aluminum-polyethylene laminated systems, cohesion failure occurred in the polyethylene layer or in the oil layer, depending on the condition of remaining oil on the aluminum surface.
