Shaped articles comprising isotactic polypropylene having a surface formed of a graft copolymer, and method of making the articles

Claim 1

A PROCESS FOR MODIFYING THE CHARACTERISTICS, PARTICULARLY THE DYEING CHARACTERISTICS, OF PERMANENTLY SHAPED ARTICLES FORMED OF POLYPROPYLENE WHICH IS PREDOMINANTLY CRYSTALLINE ISOTACTIC POLYPROPYLENE AND HAVING PEROXIDIC OXYGEN IN AN AMOUNT OF FROM 0.01 TO 1.0 G./100 G. OF THE PROPYLENE CHEMICALLY BOUND TO THE POLYPROPYLENE CHAINS AT THE SURFACE OF THE ARTICLE, WHICH PROCESS COMPRISES INTIMATELY CONTACTING THE ARTICLE AT A TEMPERATURE OF FROM ABOUT 72* C. TO 85* C. WITH A POLYMERIZABLE SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF NUCLEARLY UNSUBSTITUTED MONOVINYL PYRIDINES, NUCLEAR-ALKYL SUBSTITUTED MONOVINYL PYRIDINES, IN WHICH THE ALKYL GROUPS CONTAIN FROM 1 TO 4 CARBON ATOMS, NUCLEARLY UNSUBSTITUTED MONOVINYL QUINOLINES, N-VINYL CARBAZOLE, N-VINYL PYRROLIDONE, AND MIXTURES OF SAID MONOMERS WITH ANOTHER MONOMER COPOLYMERIZABLE THEREWITH AND SELECTED FROM THE GROUP CONSISTING OF ACRYLONITRILE, ALKYL ACRYLATES AND ALKYL METHACRYLATES WHEREBY GRAFT POLYMERIZATION OF THE POLYMERIZABLE SUBSTANCE ONTO THE POLYPROPYLENE CHAINS AT THE SURFACE OF THE ARTICLE IS INITIATED BY THE PEROXIDIC OXYGEN CHEMICALLY BOUND TO SAID CHAINS, THE MODIFICATION OF THE ARTICLE BEING CONFINED SUBSTANTIALLY TO THE SURFACE THEREOF.