282 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

This invention relates to an adhesive composition comprising a functionalized random propylene polymer (FRPP) having at least 0.1 wt % of a functional group, a heat of fusion of between 0.5 and 70 J/g, and an mm triad tacticity index of at least 75%, where the adhesive 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 (1 lb/in) 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.

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.

PCT No. PCT/JP97/01387 Sec. 371 Date Dec. 11, 1997 Sec. 102(e) Date Dec. 11, 1997 PCT Filed Apr. 22, 1997 PCT Pub. No. WO97/40075 PCT Pub. Date Oct. 30, 1997A catalyst component for polyolefin production catalysts comprising a metallocene compound represented by general formula (1) (symbols have the meanings as described in the specification), polyolefin production catalyst containing the component, and method for producing polyolefin with the catalyst are provided. Use of a catalyst containing the novel metallocene compound as a catalyst component of the invention in polymerization of alpha -olefin, particularly propylene, enables one to prepare high rigid, high melting point isotactic polypropylene useful as an industrial material for automobiles and the like, more specifically isotactic polypropylene having highly controlled stereoregulartity and regioregularity, particularly the one having a high regioregularity that has been difficult to achieve with conventional metallocene catalysts.

A process for producing an olefin polymer using a catalyst in which (A) is a solid catalyst component which includes magnesium, titanium, halogen and an electron donative compound as essential constituents; (B) is an organoaluminum component; and (C) is at least two electron donative compounds (alpha) and (beta), wherein the pentad stereoregularity of a xylene insoluble fraction of a homopolyproylene is 0<mmrr/mmmm<=0.0068 when electron donative compound (alpha) is used in combination with (A) and (B), and the pentad stereoregularity of a xylene insoluble fraction homoproplyene of a is 0.0068<mmrr/mmmm <=0.0320 when electron donative compound (beta) is used in combination with (A) and (B). A polypropylene produced in the process can be used to obtain a biaxially oriented film. (A) and (B). A polypropylene produced in the process can be used to obtain a biaxially oriented film.

The present invention provides a method for manufacturing polycarbonate, which has a high conversion rate of a propylene oxide material into a polymer and can control stereoregularity of the macromolecular structure, and a catalytic compound for the manufacturing method.

The manufacturing method of the present invention is a method for manufacturing a polycarbonate copolymer by copolymerizing an epoxide compound as a monomer with carbon dioxide in the presence of a planar tetracoordinate-type cobalt-Schiff base complex, wherein a ligand of the Schiff base is N,N′-bis(2-hydroxybenzylidene)ethylenediamine, N,N′-bis(2-hydroxybenzylidene)phenylenediamine, or a derivative thereof, and a methyl group substituted with an amino group having an asymmetrical carbon atom or an asymmetrical axis is introduced to the 3- and/or 3′-position of the benzene ring derived from the salicyl group. In addition, the catalytic compound of the present invention is a cobalt-Schiff base complex, wherein a methyl group substituted with an amino group having an asymmetrical carbon atom or an asymmetrical axis is introduced to the 3- and/or 3′-position of the salicyl group.

This invention provides a solid titanium catalyst component which comprises magnesium, titanium, halogen and an electron donor, is free from elimination of titanium when washed with hexane at room temperature, and has a titanium content decrease ratio of less than 15 % by weight when washed with o-dichlorobenzene at 90° C. The catalyst component can be prepared by a process wherein solid titanium (i) which is free from elimination of titanium when washed with hexane at room temperature is contacted with a polar compound having a dipole moment of 0.50 to 4.00 Debye to decrease the titanium content by at least 25 % by weight, whereby a solid titanium catalyst component having a weight ratio of an electron donor to titanium of at least 6 is prepared. Olefin polymerization catalyst containing the solid titanium catalyst component can be used for (co)polymerization of olefins with high activity to obtain a polyolefin of high stereoregularity in decreased quantities of a low stereoregular polyolefin.

Disclosed are a propylene block copolymer containing a crystalline polypropylene portion having a high crystallinity of a boiled heptane-insoluble component contained therein, a high stereoregularity and an extremely long mesochain, and a process for preparing said copolymer. Further disclosed is a propylene polymer composition comprising the above propylene block copolymer and at least one stabilizer selected from a phenol type stabilizer, an organophosphite type stabilizer, a thioether type stabilizer, a hindered amine type stabilizer and a metallic salt of higher aliphatic acid. The propylene block polymer of the invention is well-balanced between rigidity, heat resistance and moisture resistance, and can be favorably used for sheet, filament, injection molded product, blow molded product, etc. The propylene polymer composition of the invention has excellent properties of the propylene polymer or the propylene block copolymer, and moreover is excellent in heat stability during the molding stage, long-term heat stability and weathering resistance.

The present invention relates to one kind of catalyst component for olefin polymerization. The catalyst component is the resultant produced through contacting at least one Ti compound and the magnesium halide adduct in the general expression of MgX2-mROH-nE-pH2O, where, X is Cl or Br, R is C1-C12 alkyl group, C3-C10 cycloalkyl group or C6-C10 aryl group, E is dialkoxy compound, m is 1-5, n is 0.005-1.0, and p is 0-0.8. It is applied in polymerization of olefin, especially propylene, and has very high catalyzing activity, high tacticity, excellent hydrogen regulating sensitivity, and capacity of obtaining polymer in good granular form. It is especially suitable for use in industrial polypropylene production.

Chiral auxiliaries useful for efficiently producing a phosphorus atom-modified nucleic acid derivative with high stereoregularity, and compounds represented by the following the general formula (I) or the general formula (XI) for introducing the chiral auxiliaries.

Meltblown nonwoven compositions and processes for forming them are described herein. In one or more embodiments, the invention is directed to meltblown nonwoven fabrics having at least one elastic layer, wherein the elastic layer comprises a propylene-based polymer having an MFR greater than about 25 g/10 min. Additionally, the propylene-based polymer comprises from about 5 to about 25 wt % of one or more C₂ and/or C₄-C₁₂ α-olefins and has a triad tacticity greater than about 90% and a heat of fusion less than about 75 J/g. The present invention is also directed to processes for forming meltblown nonwoven fabrics comprising forming a molten propylene-based polymer having an MFR of at least about 25 g/10 min, forming fibers comprising the propylene-based polymer, and forming an elastic nonwoven layer from the fibers.

The invention discloses a diaphragm for a sounding device, a sounding device and an assembling method thereof. The diaphragm includes a diaphragm layer prepared by subjecting at least one of an ethylene-acrylate copolymer and an ethylene-acrylic ester-carboxylic acid copolymer to crosslinking reaction. The molecular structure of the diaphragm includes a vinyl-acrylic group. The group reduces the chemical structure symmetry of a material, reduces tacticity, and increase steric hindrance, so that the diaphragm has a high loss factor and the sounding device has a good damping effect.

The invention relates to a process for making an article subject to dynamic loading, the process comprises: (i) shaping a polymer-containing composition in the green state, the composition comprising (a) a continuous phase of a polymeric component of at least 15 wt %, based on the total weight of the polymer component of a propylene elastomer having a heat of fusion of less than 70 J/g and an isotactic triad tacticity of 50 to 99% and optionally containing units derived from a diene, the polymeric component having a density of less than 0.9 g/cm³ and (b) from 20 to 120 phr, preferably 30 to 100 phr, most preferably 40 to 90 phr based on the total weight of the polymer component of a reinforcing filler component; and (c) a peroxide curative. The composition is combined with a fibrous reinforcement which is then cured to a cure state as determined by ODR @ 170° C., 30 min MH-ML of from 5 to 80 dNm. The invention especially relates to such processes when providing under Demattia testing conditions a crack length of less than 15 mm at room temperature over 90K cycles, preferably 10 mm, more preferably 7 mm, and most preferably 4 mm, and a 10% modulus of 0.7 to 10 MPa, preferably 1.4 to 9 MPa and most preferably 2 to 8 MPa.

PCT No. PCT/JP98/02788 Sec. 371 Date Feb. 25, 1999 Sec. 102(e) Date Feb. 25, 1999 PCT Filed Jun. 23, 1998 PCT Pub. No. WO99/00428 PCT Pub. Date Jan. 7, 1999The present invention provides a solid catalyst component for polymerization of olefins obtained by allowing a solid component and an alcohol to come in contact with each other, wherein the solid component is prepared by allowing a magnesium compound, a titanium compound and an electron donor compound to come in contact with each other, and also provides a catalyst for polymerization of olefins made of the solid catalyst component, an organic aluminum compound represented by the general formula R1pAlQ3-p and an organic silicon compound represented by the general formula R2qSi(OR3)4-q. By using the catalysts in a polymerization of olefins, polyolefins excellent in stereoregularity can be obtained in high yield.

The invention relates to polymerization of 1-butene, in particular to a spherical catalyst of polybutylene-1. The catalyst consists of a carrier, an active component and a modifier, wherein the active component is titanium tetrachloride, the carrier is a magnesium chloride spherical carrier and the modifier is an electron donor compound; and the catalyst comprises the major components in percentage by mass of: 1.1-4.5% of Ti and 0.15-12.37% of electron donors. The spherical catalyst suitable for butane-1 polymerization solves the problems that the activity of the general catalyst is low, the normality of polymer is difficult to control, and the molecular weight of the polymer and the molecular weight distribution are difficult to control. The obtained polybutylene polymer has very high steric regularity, the normality of polybutylene is as high as 99%, the crystallinity of the polybutylene-1 polymer is greater than 60% and the fusion point is 130.5 DEG C. The invention can simplify the polymerizing process and save the production cost.

A metallized, multilayer film suitable for packaging applications is provided which comprises a first skin layer comprising a thermoplastic selected from the group consisting of high density polyethylene, ethylene vinyl alcohol copolymer, medium density polyethylene, linear low density polyethylene, ethylene-propylene-butylene terpolymer, propylene-butylene copolymer, and amorphous polyamide, a metallized layer adjacent to the first skin layer, and a core layer comprising high crystallinity polypropylene homopolymer with an intermolecular stereoregularity greater than 93%. Additionally, low density polyethylene, EMA, EVA, or EAA may be extrusion laminated to the metallized side of the metallized, multilayer film at a web tension sufficient to prevent metal crazing of the vacuum deposited aluminum layer. A method for making the film is also provided.

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.

This invention provides a magnesium halide adduct, whose chemical formula is MgX2-mROH-nE, where X is Cl or Br; R is C1-C12 alkyl, C3-C10 cycloalkyl or C6-C10 aryl; m is 1-5; n is 0.005-0.5; E is diol ester compound shown in formula I. The particle sizes of the magnesium halide adduct are easy to control, and the particle size distribution is narrow. The catalyst using the magnesium halide adduct as the carrier has a uniform active center distribution. When the catalyst is used for propylene polymerization, the fine powder of the polymer is obvious reduced. The catalyst shows high catalytic activity and steric regularity.

This invention provides a solid catalyst composition used for alkenes polymerization and its catalyst, this catalyst composition contains following composition's reaction product: the Composite carrying agent is produced by spray drying halogenated magnesium and gel silica, at least one diatomic alcohol esters compound and at least one compound selected from bibasic aliphatic carboxylic acid esters or aromatic series carboxylic ester, and halogenated Titanium compound.When two Internal electronic compounds of stated catalyst is used by matching, it is not only ensured to be high activity of prepared catalyst, but also ensured that prepared polymer possess good tacticity.

Use of homogeneous catalytic systems which include as a pre-catalyst a complex of a group 4 metal and a Salan ligand in the polymerization of alpha-olefins, is disclosed. The Salan ligand is characterized by a sequential diamino-containing skeleton unit which is non-symmetric, and the pre-catalysts can also be such that are devoid of a symmetry element. The disclosed polymerization results in alpha-olefin polymers such as polypropylene which are characterized by high levels of tacticity. Also disclosed are novel Salan ligands and novel complexes thereof with group 4 metals.