SEBS effect on 60Co radiation resistance behavior of PP/HDPE matrix for medical device applications

Radiation resistant polypropylene (PP) has become more and more critical in the medical industry. Composites of PP were synthesized by melting process in the presence of high-density polyethylene (HDPE) and styrene-ethylene-butylene-styrene triblock copolymer (SEBS). Under 60Co gamma-ray irradiation, all samples were characterized by mechanical properties, thermal analysis, contact angle (CA), FT-IR analysis, and SEM. Under a 20 kG y dose irradiation, mechanical properties results show that the impact strength rose from 3.28 kJ/m2 to 4.40 kJ/m2, and the tensile strength decreased by 3.52 MPa. At the same time, CA's results show that a much higher irradiation dose makes CA lower, but the higher content of SEBS, the higher CA. To confirm the presence of polar oxygen-containing groups, the FT-IR was used, and the results show that the characteristic peak intensity of carbonyl groups decreased gradually. SEM images indicate that the number of cracks and plastic particles reduced gradually, and the radiation resistance of samples enhanced by the aromatic ring structure of SEBS.