Process to produce thermoplastic elastomers

A process for producing a polypropylene composition comprising:

• selecting a first catalyst system comprising an activator and a monocyclopentadienyl transition metal compound capable of producing an amorphous polypropylene having a Mw of at least 150,000 and a Mw/Mn of less than 3;
• selecting a second catalyst system comprising an activator and another bis-cyclopentadienyl transition metal compound capable of producing a crystalline polypropylene having a Mw of less than 300,000 and a Mw/Mn of less than 3;
• provided that the first and second catalyst systems are selected such that the Mw of the amorphous polypropylene is greater than the Mw of the crystalline polypropylene;
• and
• contacting the first and second catalyst systems under polymerization conditions in a polymerization reactor with olefin monomers consisting essentially of propylene to produce a polypropylene composition comprising higher Mw amorphous polypropylene having a Mw of at least 150,000 and a Mw/Mn of less than 3 and lower Mw crystalline polypropylene having a Mw of less than 300,000 and a Mw/Mn of less than 3.