Abstract: The present invention concerns a high melt strength propylene polymer or copolymer suitable for manufacturing foams and thermoformed product exhibiting a melt strength of at least 3 g and comprising a high molar mass portion and a low or medium molar mass portion. The polymers are produced by subjecting propylene and optionally other olefins to polymerization in a plurality of polymerization reactors connected in series, employing different amounts of hydrogen as a molar mass modifier in at least two of the reactors, and carrying out the polymerization reaction in the presence of a catalyst system capable of catalyzing the formation of a high molar mass polymerization product having a MFR2 of less than 0.1 g/10 min and a low or medium molar mass polymerization product having a MFR2 of more than 0.5 g/10 min.

Abstract: Polypropylene pipes (parts by weight): 1) 100 parts of a crystalline random copolymer of propylene with 1-15% by weight of a C4-C10 ?-olefin or a crystalline random copolymer of propylene with 1-15% by weight of C4-C10 ?-olefin and with 1-7% by weight of ethylene 2) 0 to 70 parts of an elastomeric polyolefin selected from the group consisting of: (a) a copolymer of ethylene with propylene and, optionally a diene, having an ethylene content of from 17 to 45 wt % and an propylene content from 55 to 83 wt %; (b) a copolymer of ethylene with a C3-C10C ?-olefin having an ethylene/C3-C10 ?-olefin weight ratio of from 29 to 86 wt % (13C-NMR analysis) and having an Mw/ Mn ratio of less than 3.5; and 3) 0-30 parts of a polymer of ethylene having a melting temperature over 120° C.

Abstract: The present invention concerns a high melt strength propylene polymer or copolymer suitable for manufacturing foams and thermoformed product exhibiting a melt strength of at least 3 g and comprising a high molar mass portion and a low or medium molar mass portion. The polymers are produced by subjecting propylene and optionally other olefins to polymerization in a plurality of polymerization reactors connected in series, employing different amounts of hydrogen as a molar mass modifier in at least two of the reactors, and carrying out the polymerization reaction in the presence of a catalyst system capable of catalyzing the formation of a high molar mass polymerization product having a MFR2 of less than 0.1 g/10 min and a low or medium molar mass polymerization product having a MFR2 of more than 0.5 g/10 min.

Abstract: The present invention concerns a high melt strength propylene polymer or copolymer suitable for manufacturing foams and thermoformed product exhibiting a melt strength of at least 3 g and comprising a high molar mass portion and a low or medium molar mass portion. The polymers are produced by subjecting propylene and optionally other olefins to polymerization in a plurality of polymerization reactors connected in series, employing different amounts of hydrogen as a molar mass modifier in at least two of the reactors, and carrying out the polymerization reaction in the presence of a catalyst system capable of catalyzing the formation of a high molar mass polymerization product having a MFR2 of less than 0.1 g/l0 min and a low or medium molar mass polymerization product having a MFR2 of more than 0.5 g/10 min.

Abstract: The invention relates to the preparation of an &agr;-olefin polymer product having controlled stereoregularity, comprising the successive step of: (i) producing a first polymerization product by contacting under polymerization conditions an &agr;-olefin monomer with a polymerization catalyst system comprising a transition metal compound, a first organometal compound and a stereoregulating external electron donor to give a first polymerization reaction mixture; (ii) producing a second polymerization product by contacting additional &agr;-olefin monomer with the first polymerization reaction mixture. The controlled stereoregularity is achieved in such a way that in step (ii) the second polymerization product is produced in the presence of a stereoregularity controlling agent. The stereoregularity controlling agent e.g. a second organometal compound which contains, on an atom basis, more halogen per metal than the first organometal compound, or 0.01-1.

Abstract: The present invention concerns nucleated propylene polymers having a xylene soluble fraction at 23° C. of less than 2.5%, a crystallization temperature of over 124 ° C. and a tensile modulus of greater than 2,000 MPa. These polymers can be prepared by nucleating a propylene polymer with a polymeric nucleating agent containing vinyl compound units, and by polymerizing propylene optionally with comonomers in the presence of a Ziegler-Natta catalyst system primarily transesterified with a phthalic acid ester—a lower alcohol pair to provide said propylene polymer. The catalyst contains a strongly coordinating external donor.