Blown film is well known for its strong molecular orientation but the properties of its laminate have not yet been investigated. In this paper, blown HDPE films were piled up by winding around an aluminum pipe then heated in a hot air oven. During heating, the films were shrunk and pressed against each other to produce a laminated sheet or a laminated plate. To keep the molecular orientation of the blown film, the shrinkage temperature should be kept below the melting point. But if it was too low, the peeling strength of the laminate was not enough. For this reason, the temperature was controlled in the vicinity of 127°C which resulted both in high tensile strength and high peeling strength of the laminate.
The laminate was again heated at the temperature below the melting point and pressed to form a U-shaped beam. In this process, further molecular orientation was expected but the extension was not uniformly observed.
Impact absorption energy of this laminate was measured both in the flat plate form and the U-shaped beam form. The impact absorption curve was different in these forms. No delamination was observed in this impact testing.

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