C MAS NMR of irradiated poly diene s

A number of careful studies have shown that the radiation-cross-linking of cis-1,4-poly(butadiene) (cis-PBD) proceeds via a chain-reaction mechanism involving [Pg.23]

The effect of chemical composition, and dose on a range of different poly(butadiene) samples was also examined by these authors. Similar results were obtained for cis- and trans-l,4-poly(butadiene), however, even larger G-values were measured for 1,2-poly(butadiene), presumably because of the higher reactivity of pendant vinyl groups compared with internal double bonds and the close proximity of side-chains allowing a zipping chain reaction. Among [Pg.24]

Other systems investigated by this group are butyl rubber, - natural rubber sensitized with acrylates,chloroprene, chlorobutyl rubber and nitrile rubber.More recently, Perera has examined the relationship between chemical changes in radiation-grafted natural rubber, determined using MAS NMR, and mechanical properties measured using dynamic mechanical analysis. [Pg.25]