Investigating the effect of compatibilizers on environmental stress cracking resistance in polypropylene/low density polyethylene blends

The present study focuses on the effect of octylphenoxy poly(ethyleneoxy)ethanol (IGEPAL CA 630) on the environmental stress cracking resistance (ESCR) of blends of polypropylene (PP) and low-density polyethylene (LDPE) at different weight fractions without and with the addition of two compatibilizers, corresponding to styrene-ethylene-butylene-styrene (SEBS) copolymer and styrene-ethylene-butylene maleate (SEBS-g-MA). Compression molding was used after mixing the melt in a Brabender internal mixer to create the blends. ESCR of the blends was determined by exposing the blends to a solution of IGEPAL CA 630 the presence of stress. Mechanical (tensile) and thermal properties are extracted to evaluate the effect of adding the compatibilizers SEBS and SEBS-g-MA to the blend. In the environmental stress cracking (ESCR) tests, the time to failure increases with increasing PP content, despite PP's greater resistance to ESCR than LDPE. The addition of SEBS-g-MA to the blend significantly improves the flexibility and ESCR performance of PP/LDPE blends with specific weight fractions.