Abstract: A graft block copolymer is comprised of a completely saturated olefinic backbone with pendant anionic polymer side chains. The polymer is produced by copolymerizing an .alpha.-olefin with a monomer which contains a functional group which can be metallated so an anionic monomer can be polymerized therefrom, metallating the copolymer by reaction with metal alkyl or aryl compound and a metallation activator, and growing anionic polymer side chains from the copolymer backbone by reacting an anionically polymerized monomer with the metallated copolymer.

Abstract: Disclosed is a polymer composition containing:(A) from 70 to 98 parts by weight of a crystalline propylene homopolymer, or a crystalline random copolymer of propylene with ethylene and/or C.sub.4 -C.sub.10 .alpha.-olefins, containing from 0.5 to 10% by weight of ethylene and/or .alpha.-olefins [fraction (A)]; and(B) from 2 to 30 parts by weight of elastomeric copolymer of ethylene with one or more C.sub.4 -C.sub.10 .alpha.-olefins, containing from 60 to 85% by weight of ethylene, and partially soluble in xylene at 25.degree. C. [fraction (B)];wherein the composition has an intrinsic viscosity value in tetrahydronaphthalene at 135.degree. C. of the fraction soluble in xylene at 25.degree. C. ranging from 0.8 to 1.1 dl/g.

Abstract: Propylene polymer blends containinga) a propylene homopolymer having a melt flow index of from 0.001 to 5 g/10 min, as determined at 230.degree. C. under a load of 2.16 kg,b) a propylene/ethylene copolymer having an ethylene content of from 5 to 80% w/w, andc) a propylene homopolymer having a melt flow index of from 1 to 10.sup.4 g/10 min, as determined at 230.degree. C. under a load of 2.16 kg,the ratio of the melt flow index of the propylene homopolymer c) to that of the propylene homopolymer a) being within the range 10:1 to 10.sup.7 :1.The blends of the invention are high-flow materials showing a broad molecular weight distribution, and are thus readily processible.

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: This invention provides a thermoplastic elastomer powder produced by a gas polymerization process by the use of a specified catalyst system which is excellent in powder fluidity, retains a high fluidity even in a state where no substantial forming pressure is applied and can be formed by powder molding process, as well as a powder molding process using said elastomer powder and a molded product of said molding process.

Abstract: A propylene block copolymer having a high rigidity and an excellent impact strength is produced by (1) first polymerizing propylene or a mixture of propylene and another ethylenically unsaturated hydrocarbon monomer in the presence of a catalyst comprising a Ti-containing solid component (A), an organic Al compound-containing component (B) and an alkoxyl silicon compound-containing component (C), and (2) second copolymerizing, in a gas phase, propylene and another ethylenically unsaturated hydrocarbon monomer in the presence of the first crystalline polymer of step (1) by re-using the catalyst of first polymerization, and in the presence of a saturated hydrocarbon with 6 or more carbon atoms, thereby forming an elastomeric fraction incorporated into the crystalline polymeric fraction.

Abstract: A continuous process for producing a propylene-ethylene block copolymer having well-balanced properties of impact strength, stiffness, processability, etc. using a highly active catalyst, with a superior productivity is provided,which process comprisesa first polymerization step (I), carried out using a catalyst system consisting of [A] a solid catalyst component containing Ti, Mg, halogen and a polyvalent carboxylic acid ester as indispensable components, [B] an organoaluminum compound catalyst component and [C] an electron-donating compound,using two or more continuous polymerization vessels, andfeeding monomer(s) of ethylene/(ethylene+propylene) of 0 to 5% by weight, to carry out polymerization composed mainly of propylene, so as to give 60 to 95% of the total polymerized quantity;a continuous addition of a glycol compound (D) expressed by the formulaR.sup.1 --(OC.sub.m H.sub.2m).sub.n --OR.sup.2wherein m is an integer of 2 or more, n is an integer of 3 or more, R.sup.1 and R.sup.

Abstract: Disclosed are polyolefin compositionshaving high balance of stiffness and impact strength, which comprise (percentage by weight):A) 30%-60% of a propylene homopolymer or copolymer;B) 14%-30% of a fraction comprising copolymers of propylene with ethylene;C) 10%-25% of a copolymer of ethylene with a C.sub.3 -C.sub.8 .alpha.-olefin;D) 5%-45% of a mineral filler.

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 film for a first-aid sticking plaster consisting of polypropylene resin having a weight average molecular weight within a range of 80,000 to 500,000, with resin elution quantities according to cross fractionation chromatograph in ranges of 45 to 80 percent by weight at 0.degree. to 10.degree. C., 5 to 35 percent by weight at 10.degree. to 70.degree. C., 1 to 30 percent by weight at 70.degree. to 95.degree. C., and 5 to 35 percent by weight at 95.degree. to 125.degree. C.

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: Disclosed is a normally solid, high molecular weight, non-linear, substantially gel-free, propylene polymer material characterized by high melt strength due to strain hardening which is believed to be caused by free-end long chain branches of the molecular chains forming the polymer.Also disclosed is a process for making the polymer by high energy radiation of a normally solid, high molecular weight, linear, propylene polymer in a reduced active oxygen environment, maintaining the irradiated material in such environment for a specific period of time, and then deactivating free radicals in the material.Further disclosed is the use of the strain hardening polymer in extensional flow operations such as, for example, extrusion coating, film production, foaming and thermoforming.

Abstract: A process for the production of block copolymers of ethylene and an .alpha.-olefin such as propylene by using an ionic catalyst system including a metallocene component and a component having a cation capable of donating a proton and a compatible non-coordinating anion. Novel block copolymers are produced.

Abstract: Novel metallated polyolefins are produced by contacting a polyolefin having a vinylidene group in the terminal portion with organoalkali metal compound in the presence of alkali metal t-alkoxide or tertiary amine. The metallated polyolefin is used to initiate the polymerization of polymerizable monomers to produce block copolymers of at least two blocks, at least one of which is saturated polyolefin.

Abstract: Stable aqueous artificial latices having a core-shell structure are prepared from two otherwise incompatible polymers in a blend also including a copolymer of said polymers. For example, an artificial latex in which the particles have a styrene-acrylonitrile core and an EPDM shell can be prepared.

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: A method for preparing an .alpha.-olefin polymer in which an .alpha.-olefin is polymerized in the presence of a catalyst, characterized in that the catalyst is a solid obtained by making the following components (ii) and (iii) be supported in the component (i):Component (i): an organic porous polymer having an average particle diameter of 5 to 1,000 .mu.m, in which the total pore volume of all pores whose diameter is 0.006 to 10 .mu.m is 0.3 cc/g or more, and the total pore volume of all pores whose diameter is 0.05 to 2 .mu.m is 50% or more of the total pore volume of all pores whose diameter is 0.006 to 10 .mu.m;Component (ii) a compound having the structure ##STR1## in which R is a hydrocarbon group having 1 to 10 carbon atoms; and Component (iii) a compound of a transition metal which belongs to one of the Groups IVB to VIB in the Periodic Table, having at least one conjugated 5-membered cyclic ligand.

Abstract: Propylene-ethylene copolymers are obtained by two-stage polymerization from the gaseous phase in an agitated fixed bed by means of a Ziegler-Natta catalyst system that contains in addition to a titanium-containing solid component also an aluminum compound as co-catalyst, wherein as Ziegler-Natta catalyst system a system is used which, following the reaction of the titanium-containing solid component with the co-catalyst, is deactivated by reaction with carbon dioxide. The copolymers are used for producing fibers, films and moldings.

Abstract: Polypropylene based resins and compositions comprising the resin having extremely high stiffness, heat resistance and impact strength, with these properties being well-balanced, are provided. The polypropylene based resins are characterized by comprising:(1) a propylene polymer having a content of alpha-olefin other than propylene of not more than 4 mole percent, and the following properties (2), (3) and (4):(2) a pentad fraction (mmmm fraction) measured by .sup.13 C-NMR of not less than 96.0 percent,(3) a main elution fraction peak position of not less than 118.0.degree. C. and a peak half value width of less than 4.0, these values being measured by the temperature raising separation method, and(4) an intrinsic viscosity of not less than 0.5 dl/g, but not more than 5.0 dl/g; and,(5) a rubber content measured by pulse NMR of more than 25 percent.

Abstract: Disclosed is a thermoplastic olefin polymer having elastic properties comprisinga) greater than 60 to 85 parts of a crystalline polymer fraction selected from the group consisting of (i) a copolymer of propylene and at least one alpha-olefin, (ii) a polybutene-1, (iii) an ethylene homopolymer or ethylene/alpha-olefin copolymer, (iv) polymer fraction (i), (ii) or (iii) in combination with, or mixtures thereof alone or in combination with, from 10 to 90 parts, based on the thermoplastic olefin polymer, of a homopolymer of propylene;b) from about 1 up to less than 15 parts of a semi-crystalline, low density, essentially linear copolymer fraction consisting substantially of units of the alpha-olefin used to prepare c) or the alpha-olefin used to prepare c) present in the greatest amount when two alpha-olefins are used; andc) from about 10 to less than 39 parts of an amorphous copolymer fraction of an alpha-olefin and propylene, with or without a diene or a different alpha-olefin termonomer.

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: This invention concerns a "living" free radical polymerization process for preparing polymers having a narrow distribution of molecular weights.

Abstract: Polypropylene compositions having valued plasto-elastic properties, in the form of spheroidal flowable particles with an average diameter included between 500 and 7000 um having the following composition:A) 10-60 parts by weight of homopolymer polypropylene with isotactic index greater than 90, or of crystalline propylene copolymer with ethylene and/or an alpha olefin such as butene-1, pentene-1 or 4-methyl-1-pentene, containing over 85% by weight of propylene and having an isotactic index greater than 85;B) 10-40 parts by weight of a polymer fraction containing ethylene, insoluble in xylene at room temperature;C) 30-60 parts by weight of an amorphous copolymer ethylene-propylene fraction optionally containing small proportions of a diene, soluble in xylene at room temperature and containing 40-70% by weight of ethylene.

Abstract: Propylene polymer compositions having good transparency and improved impact resistance at low temperature comprising:a) 70 to 98% by weight crystalline copolymer of ethylene with propylene and/or with an alpha olefin of the formula H.sub.2 C=CHR where R is a C.sub.2-8 linear or branched alkyl radical and b) 2 to 30% by weight of an elastomeric propylene-ethylene copolymer. The portion of said copolymer b) soluble in xylene at room temperature has an intrinsic viscosity (I.V. 2) which satisfies the following relation:0.2.ltoreq.(I.V. 2/I.V. 1).times.(C.sub.2.sup.-).ltoreq.0.6where I.V. 1 is the intrinsic viscosity of the crystalline propylene copolymer, (C.sub.2.sup.-) is the ethylene weight content of b). The ratio between the ethylene weight content in b) and the weight of the xylene soluble portion is equal to or less than 1.5.

Abstract: Discosed are compositions of crystalline propylene polymers comprising (by weight):A) 30-65% of a copolymer of propylene with a C.sub.4 -C.sub.8 .alpha.-olefin, containing from 98 to 80% propylene;B) 35-70% of a copolymer of propylene with ethylene and optionally from 2 to 10% of a C.sub.4 -C.sub.8 .alpha.-olefin, said copolymer containing 2 to 10% ethylene when the C.sub.4 -C.sub.8 .alpha.-olefin is not present, and 0.5 to 5% ethylene when the C.sub.4 -C.sub.8 .alpha.-olefin is present.

Abstract: Proposed herein is a process for preparing thermoplastic elastomers, which comprises dynamically heat treating polymer particles together with a crosslinking agent, each of the polymer particles being composed of a portion comprising a crystalline olefin polymer and portions comprising an amorphous olefin polymer, the polymer particles having an average particle diameter of at least 10 .mu.m and an apparent bulk density of at least 0.2 g/ml.

Abstract: Disclosed are films and laminates which are prepared by known filming or calendering processes using heterophasic propylene polymer compositions comprising:A) 10-60 parts by weight of homopolymer polypropylene having an isotactic index greater than 90, or crystalline copolymer of propylene with ethylene and/or other alphaolefins containing more than 85% by weight of propylene and having an isotactic index greater than 85;B) 10-40 parts by weight of a semi-crystalline essentially linear copolymer containing prevailingly ethylene, which is insoluble in xylene at room temperature;C) 30-60 parts by weight of an amorphous ethylene-propylene copolymer, soluble in xylene at room temperature and containing 40-70% by weight of ethylene;said propylene polymer compositions having a ratio between the intrinsic viscosities, in tetrahydronaphthalene at 135.degree. C., of the portion soluble in xylene and of the portion insoluble in xylene at room temperature of from 0.8 to 1.2.

Abstract: A blow molded container made of a polypropylene resin obtained by injection stretch blow molding of a polypropylene resin in which the polypropylene resin is a propylene polymer composition containing from 0.0001 to 10% by weight of 3-methylbutene-1 polymer, as well as medical instruments comprising the blow molded container made of the polypropylene resin.

Abstract: Elastoplastic polyolefin compositions endowed with high flexibility, comprising:A) 10-50 parts by weight of a homopolymer of propylene with isotactic index greater than 80, or a copolymer of propylene with ethylene, another .alpha.-olefin, or combinations thereof, which copolymer contains over 85% by weight of propylene;B) 5-20 parts by weight of a copolymer fraction containing ethylene, insoluble in xylene at ambient temperature;C) 40-80 parts by weight of a copolymer fraction of ethylene and propylene or another .alpha.-olefin, or combinations thereof, and, optionally, minor portions of a diene, said fraction containing less than 40% by weight of ethylene, being soluble in xylene at ambient temperature, and having an intrinsic viscosity from 1.5 to 4 dl/g; the percent by weight of the sum of the (B) and (C) fractions with respect to the total polyolefin composition being of from 50% to 90% and the (B)/(C) weight ratio being lower than 0.4.

Abstract: The subject invention relates to segmented fluoropolymers of the A-B-A type where A is a crystallizable fluoropolymer segment, and B is a base-resistant elastomeric fluoropolymer segment, the segmented fluoropolymers being useful as thermoplastic fluoroelastomers which are highly resistant to attack by bases. The fluoroelastomers are useful, for example, in O-rings and shaft seals in internal combustion engines using aggressive oils and in oil well applications.

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 in liquid monomers being prepared in the first stage and a copolymer in the gas phase being prepared in the second stage.

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: Polypropylene impact copolymer compositions and visbroken derivatives thereof demonstrate a good balance of low temperature properties and resistance to stress whitening when the homopolymer phase is at least predominantly homopolymeric polypropylene and the rubber phase comprises a major proportion of ethylene with a minor proportion of .alpha.-olefin of at least 4 carbon atoms and a minor proportion of propylene.

Abstract: A polypropylene molding composition having syndiotactic polymer chains is obtained in a high yield by the copolymerization of propylene with ethylene or a 1-olefin of the formula R.sup.a --CH.dbd.CH--R.sup.b in the presence of a catalyst comprising a metallocene of the formula I ##STR1## in which M.sup.1 is titanium, zirconium, hafnium, vanadium, riobium or tantalum, and an aluminoxane. This molding composition has a very high molecular weight, a very narrow molecular-weight distribution and very high syndiotaxy. Shaped articles produced from the molding composition are distinguished by high transparency, flexibility, bear strength and excellent surface luster.

Abstract: Disclosed herein is a polypropylene resin composition of a high syndiotacticity comprising a substantial homopolymer of propylene, in which the ratio of the intensity of the peak attributable to the syndiotactic pentad bonds to the sum of the intensities of all the peaks attributable to the methyl groups in the spectrum of the methyl groups measured by .sup.13 C-NMR is 0.7 or more, and a copolymer of ethylene and propylene, and a preparation process thereof.

Abstract: Disclosed are films or sheets comprising an olefin polymer composition which is comprised of(a) from about 10 to 50 parts of a propylene homopolymer having an isotactic index greater than 80, or a copolymer of propylene with ethylene and/or an another alpha-olefin, containing over 80% propylene and having an isotactic index greater than 80;(b) from about 5 to 20 parts of a semi-crystalline copolymer fraction, which copolymer is insoluble in xylene at room or ambient temperature; and(c) from about 40 to 80 parts of a copolymer fraction of ethylene with propylene and/or another alpha-olefin, and optionally with minor amounts of a diene, said copolymer fraction containing less than 40% ethylene and/or other alpha-olefin, being soluble in xylene at room temperature, and having an intrinsic viscosity from 1.5 to 4 dl/g.

Abstract: A thermoplastic olefin comprising an alloy of an olefin copolymer elastomer and a propylene/comonomer random copolymer is provided. The comonomer is selected from one or more of ethylene and C.sub.4 to C.sub.10 alpha-olefins. Polypropylene is an optional component of the alloy. The alloy may be produced by melt blending, reactor blending or a combination thereof, of the various components.

Abstract: Composition of matter useful as a multifunctional viscosity index improver for lubricating oils comprising reaction product of:(i) (a) copolymer of ethylene and at least one other alpha-olefin monomer, said copolymer comprising intramolecularly heterogeneous copolymer chains containing at least one crystallizable segment of methylene units and at least one low crystallinity ethylene-alpha-olefin copolymer segment, wherein said at least one crystallizable segment comprises at least about 10 weight percent of said copolymer chain and contains at least about 57 weight percent of said copolymer chain and contains at least about 57 weight percent ethylene, wherein said low crystalliity segment contains not greater, than about 53 weight percent ethylene, and wherein said copolymer has a molecular weight distribution characterized by at least one of a ratio of M.sub.w /M.sub.n of less than 2 and ratio of M.sub.z /M.sub.w of less than 1.

Abstract: A thermoplastic elastomer composition comprising a thermoplastic elastomeric block or graft polymer comprising at least one hard segment and at least one soft segment and a vulcanizing agent, which can be molded under high shearing stress at a temperature lower than a melting or softening point of the hard sements under shear force to give a molded article having a substantially smooth surface.

Abstract: An improved method for preparing block copolymers of propylene which comprises providing a polymerizer composed of at least two reaction vessels connected to one another, substantially homopolymerizing propylene in a first step and then copolymerizing ethylene and propylene in a second step in the presence of a stereoregular catalyst, characterized by carrying out the homopolymerization of propylene in the polymerizer composed of at least two reaction vessels connected to one another in series, then introducing the resulting polymer slurry into a countercurrent washing column and countercurrently washing the slurry with propylene, introducing the washed slurry withdrawn from the lower part of the washing column into a reaction vessel in the second step connected to the washing column and performing the polymerization of ethylene and propylene, of which ratio ranges from 15/85 to 95/5. According to this method, a block copolymer of propylene exhibiting excellent physical properties can be obtained efficiently.

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: In a process for producing granular propylene block copolymers by Ziegler-Natta polymerization of an .alpha.-olefin wherein the Ziegler-Natta catalyst comprises a granular solid transition metal catalyst component and an organometal component in two steps wherein a resinous homopolymer of propylene is produced in the first step and an elastomeric copolymer of propylene with ethylene is produced in the second step, the improvement which comprises the use as the granular solid transition metal component of a mixture of the solid transition metal components, one made up substantially of particles of particle size of more than 5 microns and the other made up substantially of particles of particle size of 1 to 5 microns thereby to produce granular propylene copolymers endowed with an improved granulometric properties such as lowered tackiness and thus improved flowing characteristics. The component (B) is preferably produced from the particles for the component (A) by reducing the particle size of its particles.

Abstract: In a process for producing granular propylene block copolymers in two steps wherein a resinous homopolymer of propylene is produced in the first step and an elastomeric copolymer of propylene with ethylene is produced in the second step, the improvement which comprises conducting the second step in the presence of a granular propylene homopolymer added thereby to produce granular propylene copolymers endowed with an improved granulometric properties such as lowered tackiness and thus improving flowing characteristics.

Abstract: Propylene-ethylene copolymers are prepared in an agitated bed of solids by first polymerizing propylene from the gas phase in a first polymerization zone at 20-40 bar and 60.degree.-90.degree. C. by addition of a Ziegler-Natta catalyst system, and copolymerizing in a second polymerization zone at 7-35 bar and 40.degree.-70.degree. C. the finely divided polymer from the first polymerization zone with a mixture of olefins a process which comprises copolymerizing in the second polymerization zone with a mixture of propylene, ethylene and a further .alpha.-olefin of from 4 to 10 carbon atoms, setting the ratio of the partial pressures between propylene and ethylene within the range from 100:20 to 100:120 and that of the partial pressures between propylene and the further .alpha.

Abstract: Continuous processes for producing high melting and viscoelasting polypropylene or ethylene-propylene copolymer are provided.These processes are characterized by (1) using two or more polymerizers connected in series, (2) supplying the whole amount of a catalyst and a molecular weight regulator (hydrogen) in the first tank and (3) a degasification amount of each tank in the second and subsequent tanks being 0.5 to 10 V.sub.1 /Hr (wherein V.sub.1 is a volume of the tank) calculated at 0.degree. C. and 0 Kg/cm.sup.2 G. In the process for producing the copolymer, (4) monomers having an ethylene content of 5 wt % or less are supplied in the first step. According to the processes of the present invention, polymers having a broad molecular weight distribution and good fluidity upon extrusion molding can be obtained and operational control in production is simply made.

Abstract: A method for the treatment of melt-grafted polypropylene to improve adhesive properties thereof is disclosed. Molten grafted polypropylene, formed by melt grafting polypropylene with an alpha,beta unsaturated carboxylic acid or anhydride, is treated in melt processing apparatus with a minor amount of an aqueous solution of an alkaline material e.g. an aqueous solution of sodium hydroxide. The thus treated grafted polypropylene is separated from the aqueous solution and recovered e.g. in the form of pellets. The melt-grafted polypropylene may be formed in the melt processing apparatus prior to treatment with the aqueous solution or polypropylene that has been grafted in a previous operation may be fed to the apparatus. The treated polymer may be used in adhesive formulations.

Abstract: Liquid hydrocarbons are gelled by polyethylene block copolymers (PEBC's) to yield storage stable gels and sols that contain no metal-containing gelling agents and which compositions are thermally reversible; i.e., they melt into homogeneous liquids upon heating and upon cooling resume their previous state as a gel or sol.The PEBC gelling agents are block copolymers consisting of quasi-polyethylene crystalline "hard" blocks A and amorphous hydrocarbon "soft" blocks B. Crystallinity of the blocks A imparts the gel or sol with a sharp melting point which is dependent upon the PEBC chemical composition and concentration within the hydrocarbon. The gels and sols may contain suspended solid particles, such as powdered metals, fillers or oxidizers and are pumpable even when these suspended particles are present.

Abstract: A block copolymer of polyalkylene and halogenated polystyrene comprises the formula:S'--A--(A--S').sub.min which m is 0, 1, 3 or 4, A is a saturated polyalkylene, and S' is a nuclear brominated polystyrene having from about 0.5 to about 5 bromines per styrene unit. The polystyrene blocks are substantially free of halogen other than bromine and chlorine, and the polyalkylene is substantially free of halogen. The compositions retain the elastomeric properties of the non-halogenated form of the compounds while having significantly reduced flammability.