Process for functionalizing an ethylene-based (co)polymer comprising the step of contacting an ethylene-based (co)polymer at a temperature in the range 100-250 C. with an azide of formula (I) wherein Y is either (Ia) or (Ib) m is 0 or 1, n is 0 or 1, n+m=1 or 2, and X is a linear or branched, aliphatic or aromatic hydrocarbon moiety with 1-12 carbon atoms, optionally containing heteroatoms. ##STR00001##

A polymer composition made from or containing: (a) 60-80 wt % of a recycled polypropylene (rPP); (b) 0-0.03 wt % of a peroxide; (c) 3-7 wt % of a heterophasic propylene ethylene copolymer; and (d) 10-30 wt % of a polyolefin elastomer (POE);
wherein components (a) to (d) combine to 100%, and wherein the melt flow rate of component (a) has been increased by reaction with a peroxide to be in the range of 60 to 80 g/10 min. determined according to ISO 1133 at 2.16 kg at 230 C.

A process is provided for preparing a long chain branched polypropylene composition. The process comprises the steps of: i) providing a long chain branched polypropylene. ii) providing a poly functionally unsaturated compound, iii) optionally providing a radical initiator, iv) combining the long chain branched polypropylene, the polyfunctionally unsaturated compound, and the optional radical initiator, to provide a mixture, v) melt extruding the mixture to obtain a long chain branched polypropylene composition. A long chain branched polypropylene composition is provided which is obtainable by melt extruding a mixture comprising: (a) a long chain branched polypropylene, (b) a polyfunctionally unsaturated compound, and (c) optionally a radical initiator. Also provided is a use of a poly functionally unsaturated compound for reducing the loss of melt strength of a long-chain branched polypropylene, and preferably a reused long chain branched polypropylene, during melt extrusion.