Abstract: A catalyst for the polymerization of olefines comprises a solid catalytic component obtained by pre-polymerizing propylene in the presence of (A) a solid component containing magnesium, titanium, halogen and an electron-donating compound, (B) an organoaluminum compound, and (C) an alkylalkoxysilane represented by the formula, R.sup.1 Si(OR.sup.2)(OCH.sub.3).sub.2, wherein R.sup.1 represents a branched or cyclic alkyl group having 3 to 6 carbon atoms, and R.sup.2 represents a branched alkyl, alkenyl or alkinyl group having 3 to 6 carbon atoms; (B) an organoaluminum compound; and (D) an alkyltrialkoxysilane represented by the formula, R.sup.3 Si(OR.sup.4).sub.2 (OCH.sub.3), wherein R.sup.3 represents a linear alkyl group having 3 to 6 carbon atoms, and R.sup.4 represents a branched alkyl, alkenyl or alkinyl group having 3 to 5 carbon atoms.

Abstract: Highly flexible propylene/ethylene copolymers having a high rubber content are obtainable by two-stage polymerization from the gas phase in an agitated fixed bed by means of a Ziegler-Natta catalyst system which, in addition to a titanium-containing solid component, also contains an aluminum compound as a cocatalyst, in a first polymerization stage, propylene being polymerized at from 15 to 40 bar and from 50.degree. to 90.degree. C. and during an average residence time of the reaction mixture of from 0.5 to 5 hours and then, in a second polymerization stage, a mixture of propylene and ethylene being polymerized with the polymer discharged from the first polymerization stage, at from 5 to 30 bar, this pressure being at least 2 bar below the pressure of the first polymerization stage, and at from 60.degree. to 100.degree. C. and during an average residence time of the reaction mixture of from 0.

Abstract: There are provided a highly rigid propylenic resin which has a melt index MI in the range of 0.1 to 1.2 g/10 minutes as determined at 230.degree. C. under 2.160 kg load and also satisfies a relationship between the MI and the elongational viscosity ?Y(Pa.multidot.s)!, said relationship being represented by the expression2.0.times.10.sup.5 .times.MI.sup.-0.68 .ltoreq.Y.ltoreq.8.0.times.10.sup.5 .times.MI.sup.-0.68 ;and a blow molded article made from the above resin. The propylenic resin has favorable resistance to draw down and can produce a large-sized and lightweight blow molded article excellent in rigidity, dimensional stability and heat resistance.

Abstract: Catalytic solids based on titanium trichloride complex, usable for the stereospecific polymerisation of alpha-olefins, obtained by heat treatment, in the presence of a halogenated activating agent, of the liquid material resulting from bringing TiCl.sub.4, pretreated with an electron-donor compound, into contact with a composition (C) corresponding to the general formulaAlR.sub.p (Y).sub.q X.sub.3-(p+q)in whichR represents a hydrocarbon radical or a hydrogen atom;Y represents a group chosen from --OR', --SR' and --NR'R", in which R' and R" each represent a hydrocarbon radical or a hydrogen atom;X represents a halogen;p is an arbitrary number such that 0<p<3; andq is an arbitrary number such that 0<q<3;the sum (p+q) being such that 0<(p+q).ltoreq.3.These catalytic solids of controllable porosity permit the production of a wide range of propylene polymers, in particular the propylene and ethylene copolymers known as "block" copolymers.

Abstract: This invention relates to difunctional telechelic linear non-crosslinked polyolefins without pendant chain branched groups. The polyolefin compounds of this invention are useful for preparing high molecular weight polyesters, polyamides, polyureas and polyurethanes of high density without branching of the polymer chains, and with low permeability to gases and solvents.

Abstract: An isobutylene-based polymer as a polymer of cationically polymerizable monomers principally composed of isobutylene or a combination of isobutylene and a styrene-series monomer, generates a molded article with outstanding properties, the isobutylene-based polymer characteristically satisfying the following provisions;1. the isobutylene-based polymer has a substantially continuos molecular weight distribution on a gel-permeation chromatogram;2. the molecular weight at the highest peak on a gel-permeation chromatogram is within a range of 10,000 to 500,000; and3. the length (a) of the elution time in the lower molecular region of the mountain from the highest peak and the length (b) of the elution time in the higher molecular region of the mountain from the highest peak on a gel-permeation chromatogram, satisfy the provision represented by the formula (b)/(a).gtoreq.1.3.

Abstract: Process for the preparation of a polypropylene molding compositionA propylene block copolymer having good flow properties and a very good low temperature impact strength is obtained in a high yield if a catalyst which consists of a chiral metallocene, containing a bridge, of the formula I ##STR1## and an aluminoxane is used for the polymerization of propylene and the comonomers.The polymerization is carried out in two stages, a crystalline propylene polymer being prepared in the first stage.

Abstract: The invention is a process for the manufacture of six-armed radial asymmetric block copolymers, comprising of the steps of anionically polymerizing first polymer arms, contacting the first polymer arms with a non polymerizable coupling agent containing 6 functional groups, the amount of the first polymer arms being substantially stoichiometrically corresponding to 4 of the functional groups, anionically preparing second polymer arms, different from the first polymer arms, in the same reactor, adding a polar compound capable of increasing the reactivity of the residual functional groups of the coupling agent, reacting these residual functional groups with the second polymers arms, and recovering the asymetric polymer. The asymmetric polymers are useful in adhesive, coating, or sealant compositions and in bitumen blends for roofing, and in sound deadening or vibration dampening compositions.

Abstract: A process and system for prevention of fouling of pressure taps in a first gas phase fluidized bed polymerization reactor while avoiding sheeting during production of polyolefins in a second downstream gas phase fluidized bed polymerization reactor wherein a relatively small amount of water is added directly to the pressure taps of the first reactor.

Abstract: The present invention provides a process for the capping of a living polymer with a substituted or unsubstituted diphenyl alkylene. Diphenyl alkylene is defined to also include substituted or unsubstituted .alpha.-methoxystyrene, trans-stilbene, 1-isopropenylnapthalene and 2,4-dimethyl-.alpha.-methylstyrene.

Abstract: A propylene.ethylene block copolymer composition having a high stiffness and high-impact properties and its production process are provided,which composition is produced by using a specified Ziegler-Natta type catalyst;carrying out polymerization step (I) wherein homopolymerization of propylene is carried out by means of two or more polymerization vessels so as to afford 60 to 95% by weight based upon the total weight, and a specified range of the maximum value and the minimum value of the melt flow rates of the polymers obtained in the respective vessels; andcarrying out polymerization step (II) wherein propylene-ethylene random copolymerization is carried out by means of one or more polymerization vessels so as to afford 5 to 40% by weight based upon the total quantity,the ratio of the melt flow rate at the polymerization step (I) to the melt flow rate at the polymerization step (II) being made to fall within a specified range,whereby the resulting ethylene.

Abstract: High-flow propylene/ethylene copolymers which have a melt flow index of from 2 to 200 g/min under a load of 2.16 kg at 230.degree. C. and which may be produced from the gas phase by polymerization in two stages in an agitated fixed bed in the presence of hydrogen acting as chain stoppage regulator and using a Ziegler-Natta catalyst system comprising a titaniferous solid component which contains a magnesium compound on finely divided silicon oxide or on finely divided aluminum oxide or on a finely divided aluminum silicate having the empirical formula SiO.sub.2.aAl.sub.2 O.sub.3, where a stands for a value between 0.001 and 2, and an aluminum component, by means of a procedure comprisinga) a first polymerization stage in which propylene is polymerized under a pressure of from 20 to 40 bar and at a temperature of from 60.degree. to 90.degree. C.

Abstract: This invention relates to a process for preparation of non-crosslinked linear monofunctional and telechelic difunctional unsaturated polymers wherein the functional groups are acrylate or methacrylate groups. The average functionality number of the monofunctional unsaturated polymers is at least 0.7, as determined by nuclear magnetic resonance spectroscopy (NMR). The average functionality number of the telechelic difunctional polymers is at least 1.7, as determined by NMR. Alkyl acrylates or alkyl methacrylates are reacted with cyclic olefinic non-conjugated compounds or unsaturated hydrocarbon polymers to prepare monofunctional and difunctional polymers. The process is substantially free of side reactions comprising double bond migration and cyclization.

Abstract: The present invention provides olefin polymerization catalysts and processes for preparing a polypropylene and a propylene block copolymer using said olefin polymerization catalysts.The olefin polymerization catalyst (1) of the invention is formed from:[I-1] a contact product obtained by contacting:(A) a solid titanium catalyst component,(B) an organometallic compound catalyst component, and(C) a specific organosilicon compound;[II-1] (D) a specific polyether compound; and optionally,[III] an organometallic compound catalyst component.The olefin polymerization catalyst (2) of the invention is formed from:[I-2] a contact product obtained by contacting:(A) a solid titanium catalyst component,(B) an organometallic compound catalyst component, and(D) a specific polyether compound;[11-2] (C) a specific organosilicon compound.

Abstract: There are herein disclosed an olefin copolymer which comprises an olefin unit and a diolefin unit and in which a weight-average molecular weight is in the range of 200 to 800,000, the content of the diolefin unit is in the range of 0.002 to 30 mol%, and a ratio TUS/DOU between the total content of unsaturated groups observed in a molecular chain (TUS mol%) and the content of the diolefin unit (DOU mol%) is in the range of 0.001 to 200; an olefin graft copolymer obtained by the graft polymerization of this olefin copolymer and an olefin; a hydrogenated olefin copolymer and olefin graft copolymer thereof; and a process for preparing these copolymers.These olefin copolymers are excellent in molding/working properties and have a good thermal stability, transparency and uniformity. Therefore, they are useful as a high-performance VLDPE, LDPE, L-LDPE and HDPE, and further useful as a novel branched propylene polymer, a thermoplastic elastomer, a compatibilizing agent for other resins, and the like.

Abstract: This invention relates to difunctional telechelic linear non-crosslinked polyolefins without pendant chain branched groups. The polyolefin compounds of this invention are useful for preparing high molecular weight polyesters, polyamides, polyureas and polyurethanes of high density without branching of the polymer chains, and with low permeability to gases and solvents.

Abstract: A process for the production of an in situ particulate polyethylene blend comprising contacting a magnesium/titanium based catalyst system including a particulate precursor with one or more alpha-olefins in each of two or more reactors connected in series, in the gas phase, under polymerization conditions, with the provisos that:(a) the particulate precursor has a particle size distribution span of no greater than about 1.

Abstract: This invention relates to difunctional telechelic linear non-crosslinked polyolefins without pendant chain branched groups. The polyolefin compounds of this invention are useful for preparing high molecular weight polyesters, polyamides, polyureas and polyurethanes of high density without branching of the polymer chains, and with low permeability to gases and solvents.

Abstract: A solvent-free hot melt process, for preparing a non-thermosettable, pressure-sensitive adhesive from a tackified non-thermoplastic hydrocarbon elastomer. The process employs a continuous compounding device that has a sequence of alternating conveying and processing zones. The processing zones masticate and mix materials in them. Non-thermoplastic elastomers having high molecular weight may be readily compounded into adhesives in the process.

Abstract: Resins which are in situ catalytically produced blends of broad bimodal molecular weight distribution ethylene resin are produced. The resins of the invention are characterized by a blend of low molecular weight component and high molecular weight component with HMW component weight fraction which is greater than 0 (zero). Generally, the LMW/HMW weight fraction can be controlled within a very broad range. The resin has a molecular weight distribution, which is characterized as MFR or Mw/Mn. The bimodal molecular weight resins can be processed into films on existing equipment, and exhibit good processability in blown film production and provide film product of excellent FQR. The resin of the invention exhibits reduced tendency towards die-lip buildup and smoking in on-line operations.

Abstract: A bimetallic catalyst produces broad or bimodal molecular weight distribution polyolefin resin whose composition depends on the ratio of the concentration of the two metals of the catalyst producing the HMW and LMW components. The bimetallic catalyst produces a broad/bimodal MWD resin whose HMW and LMW components depend on the relative productivity of each of the transition metal sites of the catalyst. Water and/or carbon dioxide are cofed to the polymerization reactor at levels necessary to modify the weight fractions of the HMW and LMW components, thus achieving a target molecular weight distribution, MWD. The invention allows the resin MWD to be adjusted in the reactor. The weight fraction of the high molecular weight component decreases with the addition of the water and or the carbon dioxide and the FI of the overall product increases with a decrease in the HMW component weight fraction in the product.

Abstract: This invention relates to a process for preparation of non-crosslinked linear monofunctional and telechelic difunctional unsaturated polymers wherein the functional groups are reactive terminal groups other than vinyl groups. The average functionality number of the monofunctional unsaturated polymers is at least 0.7, as determined by nuclear magnetic resonance spectroscopy (NMR). The average functionality number of the telechelic difunctional polymers is at least 1.7, as determined by NMR. Monofunctional olefins and difunctional olefins are reacted with cyclic olefins or unsaturated polymers to prepare difunctional polymers. The process is substantially free of side reactions comprising double bond migration and cyclization.

Abstract: A process for preparing propylene block copolymers, comprising a preceding polymerization step in which a crystalline homopolymer of propylene, or a propylene-ethylene copolymer containing 7 wt. % or less of ethylene is produced in the presence of a catalyst comprising the following components (A) and (B), and a succeeding polymerization step in which the polymerization is continued in the presence of at least part of the homopolymer or copolymer, and of the following component (C) further added to give a copolymer with a polymerization ratio (weight ratio) of propylene to ethylene of from 0/100 to 90/10; the polymerization amount at the preceding polymerization step being from 30 to 95 wt.

Abstract: A process for producing ethylene-propylene block copolymer which comprises(1) The first step of reacting propylene or a mixture of propylene and ethylene in the presence of a catalyst composed essentially of(A) a solid catalyst component containing magnesium, titanium and a halogen as the indispensable ingredients,(B) an organoaluminum compound, and(C) a silicon compound (1) represented by the formula R.sup.1 R.sup.2 Si(OR.sup.3).sub.2, wherein R.sup.1 is an alicyclic hydrocarbon group of 5-20 carbon atoms and R.sup.2 and R.sup.

Abstract: Ethylene is homopolymerized in the presence of a catalyst consisting essentially of a Group 3 metal complex, preferably a scandium complex, having a bridged ligand structure. Optionally polymer blends are prepared by combining the process with another polymerization process, either in series or in parallel.

Abstract: The present invention relates to a process for producing ethylene propylene block copolymers excellent in appearance, elongation and impact resistance when molded by a gas phase polymerization which can be conducted in a stable manner.The process of the present invention comprises the first step of polymerizing propylene by using a catalyst system composed essentially of(A) a solid catalyst component containing magnesium, titanium, and a halogen as the indispensable ingredients,(B) an organoaluminum compound, and(C) a silicon compound represented by the formula R.sup.1 R.sup.2 Si(OR.sup.3).sub.2, wherein R.sup.1 is an alicyclic hydrocarbon group and R.sup.2 and R.sup.3 are each a hydrocarbon group, to form a propylene homopolymer, and the second step of then polymerizing ethylene and propylene with further addition of a silicon compound represented by the formula R.sup.4 R.sup.5.sub.a Si(OR.sup.6).sub.3-a, wherein R.sup.4 is an aromatic hydrocarbon group, R.sup.

Abstract: A method for producing asymmetric radial polymers which comprises anionically polymerizing an anionically polymerizable monomer to form a first set of living polymer arms, coupling the first set of living polymer arms with a silicon-based coupling agent, substantially completing the coupling reaction, anionically polymerizing, in the presence of the coupled first set of polymer arms, a different anionically polymerizable monomer(s) to form a second set of living polymer arms, and adding a coupling activator and coupling the second set of living polymer arms to the coupled first set of polymer arms to form the asymmetric radial polymer.

Abstract: A process for producing a copolymer of propylene and other .alpha.-olefins in the presence of a catalyst comprising a titanium-containing solid catalyst component and an organoaluminum compound is disclosed. The process comprises (1) a first step in which propylene is homopolymerized or propylene and a minor proportion of other .alpha.-olefin are copolymerized to prepare polymer particles having a pore volume of from 0.15 to 0.30 cm.sup.3 /g, and (2) a second step in which propylene and other .alpha.-olefin are copolymerized in the presence of said polymer particles. The resulting propylene copolymer particles have improved fluidity and high bulk density.

Abstract: The invention relates to a method for producing an ethylenic polymer composition, suitable for molding, at high catalytic efficiency. The ethylenic polymer composition produced has as a high melt tension when melted, and a high melt modulus (die swell ratio). The process comprises a three step polymerization of an olefin employing a transition metal catalyst, the catalyst being produced in a specific manner.

Abstract: A catalyst system for the polymerization of alpha-olefins comprising a chromium-containing catalyst and an yttrium-containing catalyst wherein the yttrium-containing catalyst is represented by the formula (Cp.sub.2 YX.sub.x).sub.y.M.sub.z L.sub.n, wherein Cp is cyclopentadienyl or cyclopentadienyl substituted with alkyl or alkyl silyl radical or radicals, X is a halogen, M is an alkali metal, L is a suitable electron donor ligand, x is 1 or 2, y is 1 or 2, z is 0 or 1, and n is a number corresponding to the value needed to form a stable complex, with the proviso that when y is 2, z and n are 0 is provided. Also disclosed is a polymerization process employing such a catalyst system, and novel olefin polymers. Polymers thus produced exhibit high bulk density and a broad molecular weight distribution.

Abstract: A process for the polymerization of ethylene and/or one or more alpha-olefins comprising contacting ethylene, and/or the alpha-olefin(s) with a catalyst comprising a first component which is a bis(cyclopentadienyl) Group IVA metal compound containing a substituent capable of reacting with a cation, and a second component which is a compound having a bulky anion containing one or more boron atoms and which is substantially non-coordinating under the reaction conditions and a cation, in which process additional first component is added.

Abstract: Process for the preparation of LLDPE with improved processability by gas phase polymerization performed in two or more reactors, wherein, whatever the order, in one of the reactors a mixture of ethylene and an alpha-olefin CH.sub.2 .dbd.CHR, where R is an alkyl having 1-10 carbon atoms, is polymerized to yield a copolymer containing up to about 20% by mole of the alpha-olefin, and in another reactor a mixture of propylene and an alpha-olefin CH.sub.2 .dbd.CHR', where R' is an alkyl radical having 2-10 carbon atoms, is polymerized to yield a copolymer containing from 5 to 40% by weight of said olefin, in an amount of 5-30% with respect to the total polymer weight and the polymer-catalyst system obtained in the first reactor is fed to the other reactors.

Abstract: Disclosed is a propylene-ethylene/butene block copolymer, comprising a polybutene component block-copolymerized with a propylene-ethylene random copolymer component, or with a polypropylene component and a propylene-ethylene random copolymer component, the content of the polybutene component being 0.1 to 10% by weight, the total content of the propylene-ethylene random copolymer component and the polypropylene component being 99.9 to 90% by weight and the content of the polypropylene component being 0 to 30% by weight, wherein the propylene-ethylene random copolymer component is composed of a copolymer comprising 15 to 80 mole % of monomer units based on ethylene and 85 to 20 mole % of monomer units based on propylene, and said block copolymer is a powder having a high molecular weight.

Abstract: Propylene is copolymerized with ethylene in solventfree polymerization in two steps where a resinous polymer is produced in the first step and a rubbery polymer is produced in the second step over a Ziegler catalyst whose solid catalyst component comprises a sub-component which is a solid catalyst component for a Ziegler catalyst comprising Ti, Mg and a halogen and which has, in accordance with the present invention, undergone mechanical milling. The solid catalyst components is specified. Less Sticky polymer powder is obtainable.

Abstract: A propylene block copolymer having good flow properties and a very good low temperature impact strength is obtained in a high yield if a catalyst which consists of a chiral metallocene, containing a bridge, of the formula I ##STR1## and an aluminoxane is used for the polymerization of propylene and the comonomers.The polymerization is carried out in two stages, a crystalline propylene polymer being prepared in the first stage.

Abstract: An elastomeric polymer composition that exhibits improved processability and green strength comprises: from about 95 to about 70 parts by weight of one rubbery polymer selected from the group consisting of butyl rubber, chlorinated butyl rubber and brominated butyl rubber and from about 5 to about 30 parts by weight of a block copolymer having an elastomeric polyisobutylene midblock and two plastomeric endblocks of polymerized monovinylidene aromatic monomers and star-shaped block copolymers having from three to six arms wherein the inner elastomeric blocks are polyisobutylene and the outer plastomeric blocs are polymerized monovinylidene aromatic monmers for a total of 100 parts by weight of the rubbery polymer and the block copolymer. Vulcanizates of the composition that exhibit reduced permeability to gases and improved tear strength are provided together with a process for their production.

Abstract: A process for producing polypropylene, which comprises preliminarily polymerizing 3-methylbutene-1 in the presence of a catalyst system formed from[A] a solid titanium catalyst component containing magnesium, titanium, halogen and polycarboxylic acid esters as essential components,[B] an organoaluminum compound, and[C] an organosilicon compound represented by the general formula R.sub.n Si(OR').sub.4-n wherein R and R' represent a hydrocarbon group, and 0<n<4, the amount of the 3-methylbutene-1 preliminarily polymerized being 0.1 to 100 g per gram of the solid titanium catalyst, and thereafter, polymerizing propylene or copolymerizing propylene and an alpha-olefin in the presence of the catalyst used in the preliminary polymerization to such an extent that the amount of the monomer or monomers polymerized is from 1,000 to 100,000 times the amount of the 3-methylbutene-1 preliminarily polymerized.

Abstract: Propylene is copolymerized with ethylene in solvent-free polymerization in two steps where a resinous polymer is produced in the first step and a rubbery polymer is produced in the second step over a Ziegler catalyst whose solid catalyst component has undergone preliminary polymerization of an .alpha.-olefin in the absence of an organoaluminum compound. The solid catalyst components is specified. Less sticky polymer powder is obtainable.

Abstract: Disclosed is a composition of polybutene-1 comprised of a polymer resulting from preliminarily polymerization of a small amount of an .alpha.-olefin, which has an intrinsic viscosity [.eta.]p of 7 dl/gram or lower, as measured at 135.degree. C. in a decalin solution; and a homopolymer of butene-1 or a copolymer of butene-1 and 20% by weight of an .alpha.-olefin other than butene-1, the composition of polybutene-1 having an intrinisic viscosity [.eta.]t of 0.5-7.0 dl/gram, when measured at 135.degree. C. in a decalin solution, and satisfying the following relationship with respect to the intrinsic viscosity [.eta.]p:[.eta.]p.ltoreq.2.5.times.[.eta.]r. The composition provides resulting films with highly improved appearance and with a lesser number of gel and fish eyes.

Abstract: Elastomeric polymers comprising polymerized alpha-olefins or conjugated alkadienes are produced by cationic polymerization in the presence of titanium tetrachloride and an electron pair donor selected from pyridine or a non-hindered alkylpyridine. The polymers have very narrow, mono-modal molecular weight distributions such a achived by anionic polymerization. Polymerization of each monomer is terminated prior to broadening of the molecular weight distribution which significantly detracts from polymer properties.

Abstract: A multistage method for making a homopolymer or copolymer of an alpha-olefin having increased stiffness and broadened molecular weight distribution.

Abstract: In the copolymerization of 4-methyl-1-pentene and at least one alpha olefin under batch polymerization conditions at a temperature of at least about 50.degree. C. wherein 4-methyl-1-pentene is initially polymerized in the absence of comonomer and then comonomer is added to the reaction vessel to permit copolymer formation, the improvement comprising initially forming 4-methyl-1-pentene homopolymer in an amount sufficient to reduce the solubility of the later formed copolymer at the polymerization temperature, said homopolymer being no more than about 5 weight percent of the end product copolymer. Also the products of such polymerizations are disclosed.

Abstract: A catalyst component for producing highly crystalline olefin polymers without causing any operational problems and stably and affording therefrom a film having very few occurrence of voids and a superior transparency, and a process for producing the catalyst component, which catalyst component comprises a linear olefin-non-olefin block copolymer having at least one linear olefin block copolymer and at leaast one non-linear olefin polymer block and (a) a titanium trichloride composition or (b) titanium, magnesium, a halogen and an electron donor as components for a carrier, the content of the linear olefin polymer block being 0.1 to 49.5% by weight, the content of the non-linear olefin polymer block being 0.01 to 49.5% by weight, the ratio by weight of the linear olefin polymer block to the non-linear olefin polymer block being 2/98 to 98/2 and in the case of (a), the content of the titanium trichloride composition being 99.89 to 1.0% by weight.

Abstract: A process for producing polypropylene, which comprises preliminarily polymerizing 3-methylbuten3-1 in the presence of a catalyst system formed from[A] a solid titanium catalyst component containing magnesium, titanium, halogen and polycarboxylic acid esters as essential components,[B] an organoaluminum compound, and[C] an organosilicon compound represented by the general formula R.sub.n Si(OR').sub.4-n wherein R and R' represent a hydrocarbon group, and 0<n<4, the amount of the 3-methylbutene-1 preliminarily polymerized being 0.1 to 100 g per gram of the solid titanium catalyst, and thereafter, polymerizing propylene or copolymerizing propylene and an alpha-olefin in the presence of the catalyst used in the preliminary polymerization to such an extent that the amount of the monomer or monomers polymerized is from 1,000 to 100,000 times the amount of the 3-methylbutene-1 preliminarily polymerized.

Abstract: A process for producing a highly transparent and highly stiff polypropylene affording a superior molded product is provided,which process comprises using a catalyst obtained by combining1 a titanium trichloride composition (III) obtained by reacting TiCl.sub.4 with an organoaluminum compound (A.sub.1) or a reaction product (I) or (A.sub.1) with an electron donor (B.sub.1) to obtain a solid product (II), followed by subjecting the product (II) to a multi-stage polymerization treatment with a linear olefin and a non-linear olefin, each once or more times used, and further reacting the resulting linear olefin-non-linear olefin block copolymer with an electron donor (B.sub.2) and an electron acceptor,2 an organoaluminum compound (A.sub.2); and as a third component,3 an aromatic carboxylic acid ester (E) or an organosilicon compound (S) having a Si--O--C bond and/or a mercapto group.

Abstract: A process for producing a propylene polymer having good flowability with an MFR of at least 10 g/10 minutes comprises a first polymerization stage consisting of at least two steps and a subsequent second polymerization stage. It is important to control the intrinsic viscositites of a crystalline propylene polymer obtained from the first step of the first polymerization stage and a crystalline propylene polymer obtained from the final step of the first polymerization stage.

Abstract: A copolymer of an .alpha.-olefin with an aromatic diolefin such as divinylbenzene produced by means of Ziegler-Natta polymerization and having a vinylphenyl moiety is subjected to polymerization with an ethylenically unsaturated monomer by means of anion polymerization or free radical polymerization, whereby a graft-modified .alpha.-olefin copolymer is obtained.

Abstract: Propylene/ethylene polymers are prepared by a process in which, in each case in the presence of hydrogen and by means of gas phase polymerization, first (A), in a first polymerization zone, propylene is homopolymerized, and the resulting propylene homopolymer is introduced into (B) a second polymerization zone, where a mixture of propylene and ethylene is then polymerized with the reaction product obtained in (A). In this process, ethylene is homopolymerized in a further polymerization zone (C), likewise by gas phase polymerization, with certain provisos, and the resulting reaction product is likewise fed to the second polymerization zone (B).

Abstract: Propylene/ethylene block copolymers are prepared by a continuous process in which, in each case in an agitated fixed bed of finely divided polymer from the gas phase, first (I) in a first polymerization zone, propylene is homopolymerized by feeding in a Ziegler-Natta catalyst system consisting of (1) a titanium component which contains titanium, magnesium, chlorine and a phthalic acid derivative, (2) an aluminumalkyl component and (3) a silane component, and (II) in a second polymerization zone, a mixture of propylene and ethylene is polymerized with the propylene homopolymer present in the reaction mixture obtained in the first polymerization zone by feeding in the said reaction mixture. In the process, (A) a titanium component (1) is used which is obtained by a method in which (1.1) first, (1.1.1) in a liquid hydrocarbon, (1.1.2) a finely divided magnesium halide, (1.1.3) an alkanol, (1.1.4) a certain phthalic acid derivative and (1.1.

Abstract: Block copolymers compose a polyisobutylene rubbery soft segment of M.sub.n of about 5,000 to above 500,000 and glassy hard segments of M.sub.n of about 5,000 or higher and usually about 10,000 to 35,000 or more, are made by preparing a living polymer block of the polyisobutylene and then polymerizing on said living polyisobutylene block the glassy hard segments by adding thereto an electron donor having a donor number of 15 to 50 and then adding and polymerizing the monomers for the glassy hard segments. The monomers for the glassy hard segments are styrene and its derivatives and indene and its derivatives and mixtures thereof.