abstract |
Disclosed is a method for viscosity breaking of a polypropylene polymer, a polypropylene copolymer or a polypropylene polymer blend, which process comprises adding a chain transfer agent and an initiator to a polypropylene polymer, polypropylene copolymer or polypropylene polymer blend and heating the resultant composition. The chain transfer agent has a Cs value of greater than or equal to about 0.04 as measured in ethylene polymerization at 130°C. The initiator is for example an organic or inorganic peroxide, a carbon based radical generator, a bis azo compound, a stable nitroxyl compound, a sterically hindered NO-acyl compound or a sterically hindered alkoxyamine compound. |