摘要 |
This disclosure relates to a method for producing polyethylene open-cell foam materials, comprising a process step of pressurized heating at a temperature of 110 DEG to 135 DEG C. of a base compound consisting of polyethylene or a copolymer of polyethylene which has been compounded with an azodicarbonamide foaming agent and a bridging agent, in order to obtain a primary intermediate product with a cubical expansion coefficient of 1.0 to 2.0 times; a process step of heating the primary intermediate product under normal atmospheric pressure at a temperature of 150 DEG DIFFERENCE 190 DEG C. and thus causing the complete decomposition of the foaming agent in order to obtain a secondary intermediate product having cell membranes capable of being easily ruptured by mechanical compression; and a process step of subjecting said secondary intermediate product to mechanical pressure in order to rupture and interconnect the closed cells; and, as needed, a foaming assist agent, or a high-melting-point resin powder, or both a high-melting-point resin powder and a foaming assist agent are added to and compounded with the base compound so that the resulting products are high-expansive or ultra-high-expansive materials with an expansion ratio of 25 times said base compound, or more, and have an open-cell ratio nof 96 DIFFERENCE 100%.
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