Abstract:
A polyolefin nanocomposite material comprising the following components: (A) a crystalline or semi-crystalline polyolefin resin; and (B) a nanosized mineral filler comprising or substantially consisting of a hydrotalcite, wherein the amount of the hydrotalcite is from 0.02 to 6 parts by weight per 100 parts by weight of the nanocomposite material, and the ratio MFR (1)/MFR (2) of the melt flow rate value MFR (1) of component (A) to the melt flow rate value MFR (2) of the polyolefin nanocomposite material is of at least 1.02, characterized in that the said polyolefin nanocomposite material includes a compatibilizer the dispersion of the mineral filler (B) and compatibilizer in the polyolefin resin is produced at shear mixing rates from 30 to 300 sec−1,
Abstract:
Plastic tanks comprising a propylene-hexene-1 copolymer having a xylene soluble fraction lower than 5% wt with respect to the total weight of the copolymer and satisfying the following relation: A · T m B > 70 wherein A is the MFR measured according to the method ISO 1133 (230° C., 5 kg) expressed in g/10 min, Tm is the melting temperature measured by DSC expressed in ° C. and B is the hexene-1 content expressed in percentage by weight with respect to total weight of the copolymer.
Abstract:
A solution process for polymerizing one or more α-olefins of formula CH2═CHR, where R is H or an alkyl radical C1-12, to produce a polyolefin soluble in the reaction medium, the process comprising:a) polymerizing said one or more α-olefins in a solution phase in the presence of a polymerization catalyst and a inert solvent having a vapor pressure lower than 100 kPa at 20° C.; b) separating the produced polyolefin from the unreacted monomers and the inert solvent by means of a sequence of at least three volatilization chambers operating at a decreasing pressure, the second devolatilization chamber being operated at a pressure from 0.8 to 5 bar.
Abstract:
Catalyst component having average particle size equal to or lower than 40 μm comprising a magnesium halide, a titanium compound having at least a Ti-halogen bond and at least two electron donor compounds one of which being present in an amount from 15 to 50% by mol with respect to the total amount of donors and selected from succinates of formula (I) below in which the radicals R1 and R2, equal to, or different from, each other are a C1-C20 linear or branched alkyl, alkenyl, cycloalkyl, aryl, arylalkyl or alkylaryl group, optionally containing heteroatoms; and the radicals R3 and R4 equal to, or different from, each other, are C1-C20 alkyl, C3-C20 cycloalkyl, C5-C20 aryl, arylalkyl or alkylaryl group with the proviso that at least one of them is a branched alkyl; said compounds being, with respect to the two asymmetric carbon atoms identified in the structure of formula (I), stereoisomers of the type (S,R) or (R,S) and at least another electron donor compound which is extractable, under the test of extractability disclosed in the characterization section, for more than 30% by mol
Abstract:
Polyolefin composition comprising, in percent by weight: A) 50-75% of a blend of polymers (PP) and (ECI), wherein (PP) is selected from the group consisting of: (i) propylene homopolymers; (ii) copolymers of propylene; (iii) combinations of said homopolymers (i) and copolymers (ii); (EC1) is a copolymer of ethylene and propylene or CH2═CHR alpha-olefin(s), where R is a 2-8 carbon alkyl radical, or a copolymer of ethylene, propylene and the said CH2═CHR alpha-olefin(s), containing from 20 to 35%, of ethylene; and B) 25-50% of a copolymer (ECII) of ethylene and propylene or CH2═CHR alpha-olefin(s), where R is a 2-8 carbon alkyl radical, or a copolymer of ethylene, propylene and the said CH2═CHR alpha-olefin(s), containing from 40 to 60% of ethylene; in which composition the copolymer component (ECI) is present in amounts from 23 to 45% with respect to the total weight of (A), and the intrinsic viscosity [ηtot] of the fraction XS soluble in xylene at room temperature, referred to the total weight of (A)+(B), is of 3.5 dl/g or more.
Abstract:
The present invention relates to catalysts systems for the polymerization of ethylene and its mixtures with olefins CH2═CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising (A) a solid catalyst component comprising Ti, Mg, halogen, (B) an aluminum alkyl compound and (C) an ether of formula ROMe in which R is an alkyl group linked to the oxygen atom through a tertiary carbon atom, and in which the molar ratio between the aluminum alkyl compound (B) and the ether compound (C) ranges from 5 to 50.
Abstract:
The present subject matter relates to processes for irradiating visbroken propylene polymer compositions or extrudates of propylene polymer compositions containing a propylene polymer having a low polydispersity index and a non-phenolic stabilizer.
Abstract:
A continuous process for minimizing the agglomeration of freshly manufactured polyolefin pellets comprising the steps of: feeding an aqueous stream containing polyolefin pellets to a tower, cooling said polyolefin pellets during their upward flow along said tower by means of a downward flow of a cooling agent having a density higher than said polyolefin, collecting the cooled pellets from the top of said tower after a residence time in the tower comprised between 2 and 20 minutes.
Abstract:
A process for the preparation of a propylene copolymer composition having a Flexural modulus lower than 500 MPa, a total ethylene content higher than 9% and a Xylene soluble fraction at room temperature higher than 20% comprising at least one polymerization step carried out in a gas-phase polymerization reactor comprising at least two interconnected polymerization zones said process being characterized by the fact that at least 30% by weight of said xylene soluble fraction is produced in the polymerization step carried out in a gas-phase polymerization reactor comprising at least two interconnected polymerization zones.
Abstract:
A catalyst component for the polymerization of olefins comprises Mg, Ti, halogen, and an alpha-omega-diether represented by the general formula: (RO)—(CR1R2)n—(OR), wherein the number of n is from 5 to 10, R is an alkyl, cycloalkyl or aryl radical containing 1 to 12 carbons, and R1 and R2 are independently from each other hydrogen, an alkyl, cycloalkyl or aryl radical containing 1 to 12 carbons. The catalysts prepared with such component provide a high mileage for the production of polyolefins with a high bulk density of the polymer produced in gas-phase polymerization process or in slurry polymerization process. Such catalyst produces narrower MWD PE, if compared with other catalyst systems.