摘要:
Polyolefin compositions comprising (percent by weight): 1) 55-90% of a crystalline propylene homopolymer or copolymer containing up to 15% of ethylene and/or C4-C10 α-olefin(s) and having values of MFR equal to or higher than 25 g/10 min; 2) 10-45% of a copolymer of ethylene with one or more C4-C10 α-olefin(s) containing from 10 to 40% of said C4-C10 α-olefin(s); said compositions having values of MFR equal to or higher than 20 g/10 min, a total content of ethylene of 20% or more, a total content of C4-C10 α-olefin(s) of 4.5% or more, a ratio of the total content of ethylene to the total content of C4-C10 α-olefin(s) of 2.3 or more, a total fraction soluble in xylene at room temperature of less than 18 wt % and an intrinsic viscosity value of the fraction soluble in xylene at room temperature of 1.7 dl/g or less.
摘要:
A propylene polymer composition having a melt flow rate (MFR) value from 3 to 30 g/10 min, comprising (percent by weight): A) 50-90% of one or more propylene copolymer(s) having a content of xylene-insoluble mojety at room temperature of not less than 85%, selected from the group consisting of propylene-ethylene random copolymers containing from 1 to 7%, of ethylene; propylene-C4-C8 α-olefin copolymers containing 2-10% of the C4-C8 alpha-olefins; and propylene-ethylene-C4-C8 α-olefin copolymers containing 0.5-5% of ethylene and 2-6% Of C4-C8 α-olefins; and B) 10-50% of a copolymer of propylene containing from 8 to 40% of ethylene and optionally 1-10% of a C4-C8 alpha-olefin; the said MFR value (MFR (2)) being obtained by subjecting to degradation a precursor composition comprising the same components A) and B) in the above said proportions, but having the MFR value (MER (1)) from 0.1 to 5 g/10 min with a ratio MFR (2) to MFR (1) of from 1.5 to 20.
摘要:
Polypropylene pipes (parts by weight): 1) 100 parts of a crystalline random copolymer of propylene with 1-15% by weight of a C4-C10 α-olefin or a crystalline random copolymer of propylene with 1-15% by weight of C4-C10 α-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 α-olefin having an ethylene/C3-C10 α-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. and intrinsic viscosity of from 2 to 6 dL/g; with the proviso that when the elastomeric polyolefin is present, the polymer of ethylene is at least 12 parts based on 100 parts of the crystalline random propylene copolymer (1) and that at least one of the layer made of the said polymer propylene composition is substantially free from random copolymers of propylene with 15 wt % or less of ethylene as the sole comonomer.
摘要:
A masterbatch composition comprising (percent by weight): A) 50%-90% of a crystalline polypropylene component comprising: AI) from 25% to 75% of a fraction having a melt flow rate MFRI of from 0.1 to 10 g/10 min.; and AII) from 75% to 25% of a fraction having a melt flow rate value MFRII equal to or lower than 100 g/10 min.; wherein the ratio MFRI/MFRII is from 5 to 60; and B) 10%-50% of a copolymer component of ethylene and at least one C3-C10 α-olefin, containing from 15% to 50% of ethylene; said masterbatch composition having a value of the intrinsic viscosity [η] of the fraction soluble in xylene at room temperature equal to or higher than 3.5 dl/g, is added to polyolefin materials to obtain final compositions suitable for injection molding.
摘要:
Crystalline polymers and copolymers of propylene having total MIL values>2 g/10 minutes, total [η] values in tetrahydronaphthalene at 135° C.≦2/8 dl/g, Mw/Mn values>20, a fraction insoluble in xylene at 25° C.≧94, and including from 10 to 60% by weight of a fraction (A) having [η]≧2.6, are prepared by way of sequential polymerization in at least two stages, in the presence of particular Ziegler-Natta catalysts supported on magnesium halides. These polymers have high melt strength, high mechanical properties, and are particularly adequate for the manufacture of articles by using various conversion technologies, such as for example extrusion in thin sheets to be subjected to thermoforming, as well as for injection molding, and blow molding.
摘要:
Polyolefin compositions comprising (percent by weight): 1) 55-80% of a crystalline propylene homopolymer or copolymer containing up to 15% of ethylene and/or C4-C10 α-olefin(s) and having an MFR value of at least 15 g/10 min, and 2) 2) 20-45 wt % of a copolymer of ethylene with one or more C1-C10 α-olefin(s) containing from 10 to 4 wt % of said C4-C10 α-olefin(s). The said compositions have values of MFR equal to or higher than 15 g/10 min, a total content of ethylene of 20% or more, a total content of C1-C10 α-olefin(s) of 4.5% or more, a ratio of the total content of ethylene to the total content of C4-C10 α-olefin(s) of 2.3 or more, and an intrinsic viscosity value of the fraction soluble in xylene at mom temperature of 1.7 dl/g or less.
摘要:
Semicrystalline polyolefin composition comprising copolymers a), b) and c) of prolylene with at least one comonomer selected from C4-C10&agr;-olefins, where the total content of recurring units from the said comonomer, referred to the composition, is equal to or higher than 6% and teh respective percentages representing the content of said recurring units in each one of the copolymers a), b) and c) are different from each other, said difference being of at least 1 unit.
摘要:
Polyolefin compositions comprising (percent by weight) A) 60%-95% of a crystalline polypropylene component having a Melt Flow Rate (MFRA) value of from 2.5 to 50 g/10 min. and containing from 20% to 80% of a fraction AI) having MFRI from 0.5 to 8 g/10 min., and from 20% to 80% of a fraction AII); B) 5%-40% of a copolymer of ethylene with one or more C4-C10 &agr;-olefin(s) containing from 10 to 40% of said C4-C10 &agr;-olefin(s); the ratio MFRA/MFRI being from 2 to 25; the percentages of A) and B) being referred to the sum of A) and B), and the percentages of AI) and AII) being referred to the sun of AI) and AII).