Preparation of Controllable Cross-Linking Polyethylene Foaming Materials and Their Properties

Abstract

In order to prepare the polyethylene materials with controlling properties, we developed two kinds of controllable cross-linking polyethylene foaming system. 2, 5-dimethyl-2, 5-bis (tert-butyl peroxy) hexane was used as cross-linking agent and TEMPO as cross-linking inhibitor, azodicarbonamide (AC) was used as foaming agent and citric acid as foaming promoter. The density, expansion ratio, cellular structure and mechanical property of these two kinds of controllable materials were studied. Experimental results show that, properties of these two kinds of materials appear similar trend: cellular size and expansion ratio are enlarged with the amount of cross-linking inhibitor or foaming promoter increasing, while density and mechanical strength appear decreasing trend. Through comparing those two material systems’ properties, cross-linking polyethelene foaming system with citric acid as foaming promoter has better properties.

Keywords

polyethylene / cross-linking inhibitor / foaming agent additives / cellular structure / mechanical property

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