Process for making block polymers or copolymers from isotactic polypropylene

A process for converting polyolefin homopolymers into block polymers or copolymers having substantially different properties from the original polyolefin homopolymer such process comprising the steps of

• introducing said polyolefin homopolymer into an extruder;
• mixing a free radical generator with said polyolefin homopolymer to form a mixture at room temperature for free radical formation;
• bringing the mass of said mixture up to a temperature of between about 175° C. to 220° C.;
• inducing chain degradation of said polyolefin homopolymer in said mixture by said free radical formation caused by said free radical generator to form degraded polymer with a melt index greater than 50;
• second mixing alkenically unsaturated monomers or polymer segments with said degraded polymer to form a second mixture;
• adjusting the temperature of said second mixture to between about 100° C. to 250° C.;
• and
• forming said block polymer or copolymer from said second mixture.