The adhesion durability of the polyethylene-coated steel with chromate treatment was investigated. The adhesion durability of polyethylene-coated steel with chromate treatment predicted from the accelerated examination result in 0.5M NaCl aqueous solution at 70 to 40ºC was in mostly agreement with the adhesion degradation durability of these polyethylene-coated steel exposed among the sea. From these results, the adhesion degradation at low temperature could be predicted by investigating of the adhesion durability in high temperature. The apparent activation energy for the time to adhesion strength at 20, 50 and 100 N/cm was investigated for various chromate treated samples. The apparent activation energy in the case of 0 mgCr/m2 was the same as that of water permeation through polyethylene coating. The apparent activation energies in the case of 100 mgCr/m2 and 300 mgCr/m2 were larger than those of water and oxygen permeation through polyethylene coating. These apparent activation energies probably show the chromate or epoxy resin dissolution reaction by corrosion production at adhesion interface. Adhesion degradation of polyethylene-coated steel with chromate treatment is influenced of dissolved oxygen. Moreover, at delaminated interfaces, the corrosion reaction by the micro cell was observed by steel surface underlying polyethylene coating. It was suggested that the degradation of adhesion interfaces resulting from the dissolution of chromate on cathodic reaction area and dissolution of steel on anodic reaction area caused adhesion degradation.

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Wood was plasma treated under atmospheric pressure of ethylene, aiming at formation of a hydrophobic surface. Wettability of treated surface was estimated by mean of contact angle of glycerine. Thickness of the deposited film on glass was measured with ellipsometory. Spectrophotometer was used to measure color difference (ΔE*) before and after plasma treatment.The hydrophobic layer of 10.5nm was deposited on a glass plate by plasma treatment at 12.75kV with 0.1L/min of ethylene flow for 5 min at atmospheric pressure. Based on the result, wood veneers were plasma treated under the same plasma conditions. Wettability of wood surfaces was decreased with the increase of treatment time, and the obtained hydrophobicity on the surface lasted after soaking in water. This treatment on wood was not recognized with eyes.

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