Radiolytic Grafting of Styrene on Polymethylpentene Film

Gamma ray initiated grafting of styrene on three polymers gave rates in the order polyethylene > polypropylene > polymethylpentene, with saturation absorption of styrene in the order polymethylpentene > polypropylene > polyethylene, indicating that the plasticizing action of absorbed styrene possibly causes increased termination rate and reduced over-all grafting rate. The rate of styrene grafting on polymethylpentene was unaffected by temperature change in the range from 23 to 85°C. Above a certain critical film thickness, styrene grafting rate is proportional to film surface area rather than film weight.