Effects of electron-beam irradiation and radiation cross-linker on tensile properties and thermal stability of polypropylene-based carbon fiber reinforced thermoplastic

Abstract

A carbon fiber reinforced thermoplastic (CFRTP) based on polypropylene (PP) matrix was irradiated by an electron-beam to study its effects on tensile properties and thermal stability at different absorbed doses. Two different types of CFRTP specimens were prepared and utilized for the irradiation experiment: neat CFRTP and CFRTP containing triallyl isocyanurate (TAIC) as radiation cross-linker for PP. The irradiation experiment was conducted on CFRTP specimens by gradually increasing the absorbed dose at 100, 200, and 400 kGy under air atmosphere. It was observed that the tensile strength and Young's modulus of both types of CFRTP were enhanced by increasing the absorbed dose. Furthermore, these properties were greatly enhanced for CFRTP containing TAIC. By observing the fracture surface of CFRTP specimens after tensile testing, it was qualitatively confirmed that interfacial adhesion between PP resin and CFs gradually improved by increasing the absorbed dose. Thermogravimetric analysis (TGA) was performed to study the thermal properties of both types of CFRTP which were irradiated at different absorbed doses. The results indicated that thermal stability of both types of CFRTP improved after irradiation, especially for CFRTP containing TAIC. We infer that the tensile properties and thermal stability of CFRTPs increased due to the enhanced adhesion between CF and resin by irradiation and TAIC addition.