PROPERTY MODIFICATION OF POLYETHYLENE TAPES BY ACETYLENE-SENSITIZED GAMMA-IRRADIATION

Gamma-irradiation techniques for improving the creep performance of po lyethylene tapes (draw ratio 6.5) have been investigated. With acetyle ne present during irradiation, the optimum dose required for maximum s uppression of yielding under tensile stress coupled with minimum embri ttlement was found to be 5-10 kGy. This is one-tenth that required for irradiation in vacuum. Creep performance was also improved at 100-deg rees-C. Creep experiments at higher loads have shown that the optimum acetylene-sensitized treatment is more effective in reducing creep rat e than the optimum vacuum-irradiation treatment.