Electron Beam Irradiation to Recrosslink Devulcanized Sulfur Cured Rubber Blended Polypropylene

Abstract

This study aims to investigate the effect electron beam (EB) irradiation on the polypropylene/devulcanized sulfur cured rubber (PP‐DVC) compound. The PP‐DVC compounds were compounded using twin‐screw extruder and then compression molded into required shapes before irradiation begins. The gel content of all irradiated PP‐DVC compounds gradually increased with higher irradiation dose indicated that the presence of DVC plays an important role in crosslinking enhancement. The mechanical properties of PP‐DVC compounds were observed marginally higher at low irradiation dosages (≤50 kGy). However, higher irradiation dosages up to 200 kGy cause adverse effect to the PP‐DVC compounds. In addition, the application of low irradiation dosage could enhance the dispersion of DVC particles at 20 phr composition in PP matrix. This also found that the scanning electron microscopy (SEM) observation where the DVC particles dispersed better in PP matrix compared to that of nonirradiated samples. Further increment in irradiation dosages up to 200 kGy reduced the crystallinity caused by chain scissoring process could rupture the crystalline structure in PP matrix. It was also found that the wavenumber of the CH and CH2 groups for irradiated samples reduced at high irradiation dosages due to the formation of carbonyl group. POLYM. ENG. SCI., 59:1017–1027, 2019. © 2019 Society of Plastics Engineers

Electron beam irradiation influencing the mechanical properties and water absorption of polycaprolactam (PA6) and polyhexamethylene adipamide (PA66)

“…This is because that the electron beam irradiation in the air causes oxidation of surface of PA and then the concentration of carbonyl groups on the surface of the sample increases. [38][39][40][41] PA66 shows lower carbonyl index under the same irradiation dose, indicating that it is less affected by irradiation and its stability is better comparing to PA6.…”

Development of propylene butene copolymer/ethylene propylene diene monomer blend foam and the effect of network structure on its reprocessing properties

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Preparation and characterization of maleic anhydride‐grafted desulfurization rubber powder by free‐radical polymerization

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