Effects of gamma irradiation and moisture absorption on mechanical properties of PA6/PTFE blends

Abstract

PA6/PTFE blends with varying polytetrafluoroethylene content from 3% to 15% (mass fraction) were irradiated by ⁶⁰Co gamma-ray with various doses (20, 50 and 100 kGy) under ambient conditions. Moisture absorption test, U-notched Charpy impact test and quasi-static tension and bending were conducted to investigate the effect of irradiation on moisture absorption and mechanical properties of the blends. It is shown that the exposure of the blend to ⁶⁰Co irradiation improves the tensile modulus, tensile strength and flexural modulus due to irradiation induced cross-linking in PA6 phase. However, the Charpy impact strength of the blends is much lower than that of the original PA6 and it decreases slightly with the increase of irradiation dose. Moreover, the flexural modulus increases to a maximum value and then decreases with further increasing the PTFE content, and the moisture absorption decreases with the increase of the PTFE content and irradiation dose.

Keywords

gamma irradiation / PA6/PTFE blends / tensile property / bending modulus / Charpy impact strength

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