Effect of metal salt of ethylene/methacrylic acid copolymer on electron beam crosslinking of low density polyethylene

Abstract

ABSTRACT:A thermoplastic resin based on ethylene/methacrylic acid copolymer (EMA) was used as a modifier for different low density polyethylene (LDPE) batches under the effect of electron beam irradiation. The EMA resin was used in the zinc metal form at a constant ratio of 9 wt% in all preparations. The effect of EMA resin as a crosslinking agent was characterized by percentage gel fraction, tensile mechanical, and differential scanning calorimetry (DSC). In this study, the maximum gel content (G max ) and gelling dose (D gel ) parameters were determined by applying the familiar Charlesby-Pinner relationship. The results showed that the gel content for all investigated samples gradually increases with increasing irradiation dose. The modified LDPE batches with EMA show higher gel content than unmodified ones at any irradiation dose. Also, the gel content of all LDPE composites decreases as a result of post-storage effect. The mechanical properties (tensile strength and elongation at break) exhibit significant change as a result of irradiation and blending the LDPE batch with EMA. The level of

Radiation and postirradiation crosslinking and structure of two unsaturated polyester resins

“…The postreaction course largely depends on polymer under consideration, and, for some polymers, no postirradiation changes were detected, or they vary depending on how the samples have been stored. In other cases, the postreaction can last up to a year or more [7] and significantly affects the overall radiation reaction conversion. Postirradiation degradation also occurs.…”