Effect of Radiation Modification on the Mechanical Properties of Linear Low Density Polyethylene (LLDPE) and Linear Low Density Polyethylene/ Ethylene Vinyl Acetate Blend for Electrical Insulations

The mechanical properties of linear low density polyethylene/ ethylene vinyl acetate (LLDPE/ EVA) blend cross-linked using electron beam (EB) irradiation was studied. The indication of ultimate strength increment showed as the irradiation dose increased from 13 to 15 MPa and 9.8 to 11.5 MPa for LLDPE and LLDPE/ EVA respectively with the exposure from 60 kGy to 120 kGy. However, the presence of EVA in LLDPE/ EVA reduced the values of ultimate strength.In contrast, the gel content with the presence of EVA in LLDPE/ EVA is much higher than the LLDPE. Besides that, the morphological analysis, gel content and the electrical properties was studied to compare the effect of presence of EVA and the increment of irradiation exposed to the samples. Consequently, the addition of EVA in the blend not only aggravates the ultimate strength but increased the gel content of the blend due to amorphous region presence in the molecular structures. Meanwhile, the increment of irradiation dose indicated the same increment trend of mechanical and electrical properties for both formulated blends. (author)