289 results about "Tacticity" patented technology

The present invention relates to a composition comprising 1) from 1 to 98 weight % of a first propylene polymer having a melting point of 100° C. or more, 2) from 5 to 98 weight % of a second propylene polymer having a heat of fusion of 70 J / g or less and a tacticity index of 75% or more, 3) from 0.5 to 75 weight % of a non-functionalized plasticizer (“NFP”) having a viscosity index of 120 or more, based upon the weight of the first polymer, second polymer, and the NFP, and articles therefrom

A method for polymerization or copolymerization of alpha -olefin, characterized in that the polymerization is performed using a solid complex titanium catalyst comprising magnesium, a halogen-containing titanium compound, and internal electron donors; organometallic compounds of metals belonging to Groups I and III on the periodic table of elements; and, as external electron donors, a mixture of three or more kinds of organic silicon compounds, from which homopolyolefins having MFR less than 5, MFR in the range from 5 to 20, and MFR greater than 20 are polymerized under the same polymerization conditions. By use of the present invention it is possible to produce an olefin polymer with high stereoregularity, broad molecular weight distribution, and good fluidity, at high rates of yield.

Disclosed herein is an adhesive composition comprising: a random propylene polymer component having a heat of fusion of between 1 and 70 J / g and an mm triad tacticity index of at least 75%; and a functionalized polymer component comprising a C2-C20 olefin comprising at least 0.1 wt % of a functional group; wherein the adhesive composition has a T-Peel adhesion on a polar substrate at 20° C. of at least 175 N / m (1 lb / in) and a T-Peel adhesion on a non-polar substrate at 20° C. of at least 175 N / m Pa (1 lb / in) and where the polarity of the polar substrate is at least 0.10 units higher than the polarity of the non-polar substrate. Methods to produce the adhesive and articles comprising the adhesive are also disclosed.

Solid catalyst components and catalysts which contain (a) magnesium compound, (b) titanium tetrachloride, and (c) a phthalic acid diester or its derivative are useful in the synthesis of olefin polymers in high yields. Particularly, propylene polymers can be obtain in very high yields while retaining high stereoregularity.

Use of homogeneous catalytic systems which include as a pre-catalyst a complex of a Group IV metal and a salalen ligand in the polymerization of alpha-olefins, is disclosed. The alpha-olefin polymers obtained are characterized by controlled levels of tacticity. Also disclosed are novel salalen ligands and novel complexes thereof with Group IV metals.

A process for polymerizing an alpha-olefin using either a catalyst formed by contacting a highly active solid titanium catalyst component, an organo-metallic compound of a metal of Group 1 to 3 of the periodic table, an organic halogen compound or a transition metal compound, and an organosilicon compound or a sterically hindered amine in an inert medium in the absence of an alpha olefin, or a catalyst prepared by preliminarily polymerizing an alpha olefin in the presence of a catalyst comprising the above four catalyst components, provided that the last one is an optional component. This process achieves the industrially advantage that the catalysts are highly active, and give a polymer having excellent stereoregularity.

Methods for making a crosslinked elastomeric composition and articles made of the same are provided. In at least one specific embodiment, an elastomeric composition comprising at least one propylene-based polymer is blended with at least one component selected from the group consisting of multifunctional acrylates, multifunctional methacrylates, functionalized polybutadiene resins, functionalized cyanurate, and allyl isocyanurate; and blended with at least one component selected from the group consisting of hindered phenols, phosphites, and hindered amines. The propylene-based polymer can include propylene derived units and one or more dienes, and have a triad tacticity of from 50% to 99% and a heat of fusion of less than 80 J / g. The blended composition can then be extruded and crosslinked. The extruded polymer can be crosslinked using electron beam radiation having an e-beam dose of about 100 KGy or less. The crosslinked polymers are particularly useful for making fibers and films.

Use of homogeneous catalytic systems which include as a pre-catalyst a complex of a Group IV metal and a salalen ligand in the polymerization of alpha-olefins, is disclosed. The alpha-olefin polymers obtained are characterized by controlled levels of tacticity. Also disclosed are novel salalen ligands and novel complexes thereof with Group IV metals.

Disclosed are highly filled thermoplastic olefin compositions and, in particular, thermoplastic olefin compositions that comprise propylene / alpha-olefin copolymers and a high level of organic or inorganic filler. Specifically, the description addresses a filled polymer composition comprising: (a) a first polymer component comprising propylene copolymer having a heat of fusion<about 75 J / g and a triad tacticity of from about 50% to about 99%, the first polymer component having a melt flow rate at 230° C.≦about 800 g / 10 min.; and (b) at least about 15% by weight of a filler, based on the total weight of the filled composition. Such compositions are useful as sound barriers, flame retardant compositions, roofing membranes, and the like.

The present invention relates to a method of homo- or co-polymerization of alpha-olefin by means of using a catalyst system which comprises the following components: (1) a solid complex titanium catalyst produced by means of a production method comprising the following steps: (a) preparing a magnesium compound solution by dissolving a magnesium halide compound and a compound of Group IIIA of the Periodical Table in a solvent of mixture of cyclic ester, one or more types of alcohol, a phosphorus compound, and an organic silane; (b) precipitating the solid particles by reacting said magnesium compound solution with a transitional metal compound, a silicon compound, a tin compound, or the mixture thereof; and (c) reacting said precipitated solid particles with a titanium compound and electron donors; (2) an organometallic compound of metal of Group IIIA of the Periodical Table; and (3) external electron donors comprising three or more types of organo-silicon compounds, wherein the melt flow rates of the homopolymers obtained from polymerization by individually using said organo-silicon compounds under the same polymerization conditions are 5 or less, 5~20, and 20 or higher, respectively. According to the present invention, it has an advantage of obtaining polymers of broad molecular weight distribution with high hydrogen reactivity and melt flow rates while maintaining high stereoregularity and yields for olefin homo- or co-polymers during homo- or co-polymerization of alpha-olefin having three or more carbon atoms.