| 摘要 |
A polymeric material prepared by polymerizing aliphatic hydrocarbons such as ethylene and propylene in the presence of a catalyst obtained by mixing a reducing metal compound such as an aluminium trialkyl or dialkyl aluminium halide with a reducible compound of a metal selected from Groups IVa, Va, VIa or VIII of the Periodic Table, such as titanium tetrachloride, is subjected to gamma rays in an oxygen-containing gas, such as air, to reduce its molecular weight.ALSO:A polymeric material prepared by polymerizing aliphatic hydrocarbons such as ethylene and propylene in the presence of a catalyst obtained by mixing a reducing metal compound such as an aluminium trialkyl or dialkyl aluminium halide with a reducible compound of a metal selected from Groups IVa, Va, VIa or VIII of the Periodic Table, such as titanium tetrachloride, is subjected to gamma rays in an oxygen-containing gas, such as air, to reduce its molecular weight. |
