Investigation of the radiation crosslinked foams produced from metallocene polyolefin elastomers/polyethylene blend

In order to produce low-density crosslinked foam of superior properties having a uniform cell structure from POEs/LDPE blends, the crosslinking efficiency of resin, behavior of crosslinking sensitizer, mechanical properties according to the irradiation dose, and compressive strength in different cell sizes have been examined. When POE/LDPE (70/30) was irradiated at 3 Mrad, the gel content was 18.5%, but the addition of 0.3 phr of TATM only increased gel content up to 36%. The lower the melt index of the resin, the more the gel fraction increase was confirmed. Although tensile strength increased up to a certain point in proportion to the gel content, the decrease of tensile strength was observed over the fixed gel content. The effect of polyfunctionality was investigated by analyzing the gel fraction in accordance with the number of double bonds in molecules of crosslinking sensitizers. As a result of the measurement of changes on compressive strength according to the sizes of different foam cells, having the same degree of density, bigger cells showed stronger compressive strengths when compressed at 25%, while foams containing smaller cells showed superior compressive strengths when compressed over 50%.