Readily dyeable compositions comprising polypropylene consisting prevailingly of isotactic macromolecules and method of preparing same

Claim 1

A PROCESS FOR PRODUCING MOLDED ARTICLES OF LINEAR, REGULAR HEAD-TO-TAIL POLYPROPYLENE CONSISTING OF OVER 50% OF ISOTACTIC MACROMOLECULES HAVING MODIFIED DYEING PROPERTIES THROUGHOUT THE CROSS-SECTION THEREOF, WHICH PROCESS COMPRISES THE STEPS OF MIXING THE POLYPROPYLENE WITH FROM 1% TO 25% BY WEIGHT OF A MONOMER SELECTED FROM THE GROUP CONSISTING OF MALEIC ACID, ESTERS OF MALEIC ACID, HALIDES OF MALEIC ACID, AMIDES OF MALEIC ACID, NITRILE OF MALEIC ACID, FUMERIC ACID, ESTERS OF FUMARIC ACID, HALIDES OF FUMARIC ACID, AMIDES OF FUMARIC ACID, NITRILE OF FUMARIC ACID, ACRYLIC ACID, ESTERS OF ACRYLIC ACID, HALIDES OF ACRYLIC ACID, AMIDES OF ACRYLIC ACID, NITRILE OF ACRYLIC ACID, STYRENE DIVINYLBENZENE AND NITROSTYRENE TO OBTAIN A HOMOGENOUS MIXTURE, HEATING THE MIXTURE AT A TEMPERATURE BETWEEN ABOUT 170*C. AND ABOUT 250*C. FOR AT LEAST FIVE MINUTES TO OBTAIN A HOMOGENEOUS MELT, INTRODUCING THE MELT INTO AN EXTRUDER IN WHICH IT IS MAINTAINED AT A TEMPERATURE BETWEEN ABOUT 140*C. AND 250*C. TO OBTAIN A HOMOGENEOUS MASS CONSISTING OF THE POLYPROPYLENE HAVING SHORT POLYMERIC CHAINS OF THE POLYMERIZABLE MONOMER SUBSTANTIALLY UNIFORMLY DISTRIBUTED ALONG AND CHEMICALLY BONDED TO THE MAIN CHAINS OF THE ISOTACTIC MACROMOLECULES, AND EXTRUDING SAID MASS, AT THE SELECTED TEMPERATURE BETWEEN ABOUT 140*C. AND 250*C., THROUGH A SHAPING DEVICE TO OBTAIN THE SHAPED ARTICLE.