| 摘要 |
Low pressure, linear polyethylene having a ratio of weight average molecular weight to number average molecular weight of less than 4 : 1 may be obtained either (i) by fractionation wherein a non-solvent is added in one or more stages to a solution of low pressure polyethylene, e.g. addition of propanol to a xylene solution, followed by separation of the precipitated polymer, or (ii) by degradation wherein a solution of low pressure polyethylene is subjected to ultra-sonic vibrations. Other properties of the product are specified. |
