ELECTRON-INDUCED CROSS-LINKING OF POLYPROPYLENE WITH THE ADDITION OF HYDROGEN-DONATING HYDROCARBONS

Electron-induced crosslinking of polypropylene with the addition of hy drogen-donating hydrocarbons produced from petroleum (HHAP) together w ith A-TMPT (trimethylpropanetriacrylate) was studied, and the followin g results were obtained: (1) Effective crosslinking was achieved at lo wer doses under 10 kGy. (2) HHAP functions as an effective radical sca venger to suppress scissions. (3) Distinguished improvements in proper ties such as elongation and heat distortion temperature were achieved by the irradiation. (4) Distinct diminution in melt flow rate and evid ent increase in average molecular weight with the irradiation at lower doses were observed. (5) It was confirmed that the oxidative degradat ion during mixing and molding was noticeably inhibited by the addition of HHAP. This effect as an antioxidant during these procedures along with the irradiation seems to be a cause to promote crosslinks. These effects are attributable to the high radical scavenging effects of HHA P and its pure hydrocarbon constitution without functional groups cont aining heteroatoms. (C) 1997 John Wiley & Sons, Inc.