Impact of Electron Beam radiation, Devulcanization Techniques, and particulate Filler on the Properties of Polyethylene/devulcanized waste rubber Composites

Mechano-chemical and microwave (MW) methods were used to devulcanize waste rubber (WR) at room temperature. Tetramethyl thiuram disulfide (TMTD) and mercaptobenzothiazole disulfide (MBTS) were used in the mechano-chemical process. The composites undergo comparative mechanical investigation after being exposed to EB irradiation at various radiation doses up to 200 kGy. The characteristics of the composites including polyethylene (PE)/devulcanized rubber (DWR)/silica were examined in relation to the concentration of silica and the dosage of electron beam (EB) irradiation. Various silica concentrations - 10, 20, and 30 phr (part per hundred parts of blend) - were employed. An excellent PE/DWR interaction was confirmed by the morphological micrographs, particularly when TMTD was used as a devulcanizing agent. The effective interaction of the PE with DWR was confirmed by the tensile strength (TS) tests of the manufactured composites, which were conducted in the following order: TMTD, MW, and MBTS. Silica and PE are not reactive, as confirmed by the DSC thermograms of PE/DWR, which show that adding silica between 10 and 30 phr had no influence on the melting point of PE. The crystallinity data for all composites loaded by DWR (devulcanized using different techniques) clearly show that as the content of silica increased, the percentage of crystallinity decreased.