Polyethylene internal double bonds

Although the production of molecular hydrogen was not monitored in this study, 13c NMR was an excellent technique to follow the production of internal double bonds, intermolecular links and the disappearance of terminal vinyl groups. Additionally, it was observed that saturated end groups are apparently produced during irradiation of polyethylene. 

The yield of internal double bonds is very mudi the same in various samptes of polyethylene [40]. This should be reflected in a stationary concentration of interme ry products formed in the initial stages of irradiation. The concentrations of vinylenes in the crystalline and noncrystalline regions were found to be ual. A suggestion has been made that both cis and trcms configurations were produced in the noncrystalline phase whereas only trans vinylenes appeared in the crystal. Concerning the methyl ends, concentration in the noncrystalline regions were approximately double those in the crystal. 

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