Abstract: A polyolefin resin composition containing an ethylene-.alpha.-olefin copolymer having: (A) a density d of 0.86 to 0.96 g/cm.sup.3 ; (B) a melt flow rate MFR of 0.01 to 200 g/10 min; (C) a molecular weight distribution Mw/Mn of 1.5 to 4.5; (D) a composition distribution parameter Cb of 1.08 to 2.00; and (E) an orthodichlorobenzene-soluble content X (wt %), at 25.degree. C. a density of d (g/cm.sup.3) and a melt flow rate MFR (wt %) satisfying that: (i) when the density (d) and the melt flow rate MFR satisfy relationship (I):d-0.008.times.logMFR.gtoreq.0.93 (I)the orthodichlorobenzene-soluble content X satisfies relationship (II):X<2.0 (II)(ii) when the density d and the melt flow rate MFR satisfy relationship (III):d-0.008.times.logMFR<0.93 (III)the orthodichlorobenzene-soluble content X satisfies relationship (IV):X<9.8.times.10.sup.3 .times.(0.9300-d+0.008.times.logMFR).sup.2 +2.

Abstract: The present invention is directed to a process of atom (or group) transfer radical polymerization for the synthesis of novel homopolymer or a block or graft copolymer, optionally containing at least one polar group, with well defined molecular architecture and narrow polydipersity index, in the presence of an initiating system comprising (i) an initiator having a radically transferrable atom or group, (ii) a transition metal compound, and (iii) a ligand, the present invention is also directed to the synthesis of a macromolecule having at least two halogen groups which can be used as a macroinitiator component (i) to subsequently form a block or graft copolymer by an atom or group transfer radical polymerization process; the present invention is also directed to a process of atom or group transfer radical polymerization for the synthesis of a branched or hyperbranched polymer; in addition, the present invention is directed to a process of atom or group transfer radical polymerization for the synthesis of a mac

Abstract: An olefin (co)polymer composition comprising, as major components, (a) 0.01 to 5 parts by weight of an olefin (co)polymer having an intrinsic viscosity [.eta..sub.a ] as measured in 135.degree. C. tetralin of 15 to 100 dl/g and (b) 100 parts by weight of an olefin (co)polymer obtained by using a metallocene catalyst and having an intrinsic viscosity [.eta..sub.b ] as measured in 135.degree. C. tetralin of 0.2 to 10 dl/g. When polyethylene having a high degree of polymerization is produced before a so-called metallocene catalyst is used to polymerize, e.g., propylene in the presence of the polyethylene as a component of a catalyst composition, a polypropylene composition having a high melt tension and a high crystallization temperature is produced.

Abstract: The invention relates to separating materials based on supports containing hydroxyl groups, whose surface [sic] are coated with covalently bound polymers, and to processes for their preparation. The separating materials are characterized in that the polymers consist of identical recurring units of the formula I.brket open-st.CH.sub.2 --CHX.brket close-st..sub.n (I)in whichX is CO--NH--CH.sub.2 --CH.sub.2 --SO.sub.3 H andn is 2-100.

Abstract: The present invention is directed to a process of atom (or group) transfer radical polymerization for the synthesis of novel homopolymer or a block or graft copolymer, optionally containing at least one polar group, with well defined molecular architecture and narrow polydispersity index, in the presence of an initiating system comprising (i) an initiator having a radically transferrable atom or group, (ii) a transition metal compound, and (iii) a ligand; the present invention is also directed to the synthesis of a macromolecule having at least two halogen groups which can be used as a macroinitiator component (i) to subsequently form a block or graft copolymer by an atom or group transfer radical polymerization process; the present invention is also directed to a process of atom or group transfer radical polymerization for the synthesis of a branched or hyperbranched polymer; in addition, the present invention is directed to a process of atom or group transfer radical polymerization for the synthesis of a ma

Abstract: A propylene block copolymer having a specified composition and consisting of a xylene soluble portion at 20.degree. C. in an amount of 5 wt % or more and a portion excluding the CXS portion, the melting temperature of the CXIS portion measured by a differential scanning caloriemeter being 130 to 155.degree. C., wherein the difference in transparency in terms of haze between prior to and posterior to the 1-hour treatment at 110.degree. C of a 150 .mu.m thick film obtained by forming said copolymer into a film by extrusion is 8% or less.According to the present invention, a block copolymer having a good transparency and improved impact resistance at a low temperature, and further exhibiting less bleeding at high-temperature heat treatment, can be provided.

Abstract: Disclosed is a graft copolymer (A+B) of a styrene-based monomer (A) and a terminal styrene derivative-modified olefin-based macromer (B) of formula (1), having a high degree of syndiotacticity for the stereospecificity of the chains derived from the styrene-based monomer: ##STR1## R is H or alkyl; X is H, halogen, or a substituent having one or more of C, Sn and Si; n is 1 to 4; m is 0 or a natural number; Z is a chain moiety derived from an olefin-based monomer. The copolymer is prepared by copolymerizing (A) and (B) in the presence of a catalyst comprising (a) a transition metal compound, (b) (i) a specific oxygen-containing compound and/or (ii) a compound capable of reacting with the compound (a) to form an ionic complex, and optionally (c) an alkylating agent.

Abstract: Blends of olefin polymers and syndiotactic vinyl polymers are produced by the catalytic polymerization of olefins and aromatic vinyl compounds or methacrylate esters as vinyl compounds in inert diluents in the presence of a catalyst mixture of transition metal compounds, metalloxane compounds and metal alkyl compounds.The blends have a finely dispersed distribution of the blending components and are suitable for the production of films, sheets, fibers, panels, coatings, pipes, hollow objects, injection molded products and foams.

Abstract: This invention describes the use of liquid block isoprene-butadiene copolymers of approximately 25,000 to 100,000 .sub.v molecular weight, and which comprises 10 to 90% by weight isoprene and 90 to 10% by weight butadiene. This material is added to a rubber compound that contains natural rubber, isoprene rubber, styrene butadiene rubber and butadiene rubber, or blends thereof, the sum of which is equal to or greater than 50 phr of the entire rubber content formulation. The liquid block copolymer is used at low levels, typically 1.5 phr to 15 phr. The invention also includes tires with at least one component composed of such rubber composition such as a tire tread.

Abstract: Homopolymers or copolymers obtained by a multistage process of olefins having the formula CH.sub.2 .dbd.CHR, in which R is hydrogen or R has from 1 to 10 carbon atoms and is an alkyl, cycloalkyl or aryl group, the process comprising:(A) a first stage of polymerization in which one or more of the olefins are polymerized in the presence of a titanium or vanadium catalyst;(B) a treatment stage in which the product obtained in the first stage of polymerization (A) is brought into contact with a compound capable of deactivating the catalyst present in the stage (A); and also brought into contact with a compound of a transition metal M selected from the group consisting of Ti, Zr, V, or Hf containing at least one M-.pi. bond and optionally with an alkyl-Al compound; and(C) a second stage of polymerization in which one or more of the olefins are polymerized, in one or more reactors, in the presence of the product obtained in treatment stage (B).

Abstract: A propylene-ethylene copolymer composition is obtained which has good moldability and an excellent balance of rigidity, toughness, and impact-strength. The composition has a melt flow rate of 10 to 300 g/10 minutes and is obtained by producing 60 to 95% by weight, based on the weight of whole polymer, of a propylene polymer having a melt flow rate (ASTM D1238) in the range of 100 to 1,000 g/10 minutes and having a ratio (Cf) of integrated values of the propylene polymer dissolved in o-dichlorobenzene at a temperature of lower than 112.degree. C., and a temperature of 112.degree. C. or higher, respectively, of 0.5 or less, by carrying out polymerization of propylene in the presence of a highly stereoregular catalyst and hydrogen in a polymerization step (I), and then producing 5 to 40% by weight, based on the weight of whole polymer, of an ethylene-propylene copolymer by feeding ethylene and propylene to the propylene polymer to react so that the content of ethylene becomes 30 to 80% by weight.

Abstract: A chemically bonded olefin block copolymer consists essentially of chemically bonded polypropylene and poly(ethylene-co-propylene). The block copolymer is obtained by a process of (1) introducing a Ziegler polymerization catalyst based on titanium and propylene to a first polymerization zone (a) and polymerizing the propylene in the polymerization zone (a) for a period of 0.01 to 0.130 seconds and withdrawing an effluent stream of polypropylene, catalyst, solvent and unreacted propylene therefrom; (2) introducing the effluent stream to a second polymerization zone (b) together with ethylene dissolved in a solvent and carrying out a polymerization reaction in the second polymerization zone (b) for a period of 0.01 to 0.130 seconds; and (3) recovering the block copolymer.

Abstract: A propylenic resin which is a homopolymer of propylene or a copolymer of propylene, has (i) intrinsic viscosity [.eta.] measured in decaline at the temperature of 135.degree. C. in the range of 0.5 to 10 deciliter/g and (ii) content of insoluble fraction in boiling n-heptane (W) in the range of 10 to 99 weight % and shows (iii) relation between relaxation time of rubber component measured by pulse NMR at the temperature of 30.degree. C. [T.sub.2H.sup.R (30): .mu.s], relaxation time of rubber component measured by pulse NMR at the temperature of 80.degree. C. [T.sub.2H.sup.R (80): .mu.s] and the content of insoluble fraction in boiling n-heptane (W) satisfying the following equations:T.sub.2H.sup.R (80).ltoreq.670-2.2.times.WT.sub.2H.sup.R (80)/T.sub.2H.sup.R (30).ltoreq.8.8+0.086.times.

Abstract: A process for preparing a propylene polymer composition having excellent rigidity, heat resistance and impact resistance, the process comprising conducting multistage polymerization including a step (a) for preparing a propylene (co)polymer (a), a step (b) for preparing a propylene-olefin copolymer (b) and a step (c) for preparing an ethylene-olefin copolymer (c) in the presence of (A) a transition metal compound and (B) a compound activating the transition metal compound (A), in which the steps (a), (b) and (c) may be carried out in any order, each of the second and subsequent stage polymerizations is carried out in the presence of a polymer or polymers obtained by the preceding stage or stages, respectively, and the resulting propylene polymer composition contains the propylene (co)polymer (a) in an amount of 20 to 90% by weight, the propylene-olefin copolymer (b) in an amount of 5 to 75% by weight and the ethylene-olefin copolymer (c) in an amount of 5 to 75% by weight, and has MFR, as measured at 230.

Abstract: The invention relates to a high-molecular-weight reactor blend comprising a high-molecular weight polypropylene and a high-molecular weight ethylene-propylene copolymer and having an ethylene content in the range from 0.1 to 2% by weight based on the total amount of blend, a melt flow index MFR (230/5) of .ltoreq.5 dg/min and a molecular weight distribution M.sub.w /M.sub.n in the range from 6 to 20.

Abstract: The present invention is directed to a process of atom (or group) transfer radical polymerization for the synthesis of novel homopolymer or a block or graft copolymer, optionally containing at least one polar group, with well defined molecular architecture and narrow polydispersity index, in the presence of an initiating system comprising (i) an initiator having a radically transferrable atom or group, (ii) a transition metal compound, and (iii) a ligand; the present invention is also directed to the synthesis of a macromolecule having at least two halogen groups which can be used as a macroinitiator component (i) to subsequently form a block or graft copolymer by an atom or group transfer radical polymerization process; the present invention is also directed to a process of atom or group transfer radical polymerization for the synthesis of a branched or hyperbranched polymer; in addition, the present invention is directed to a process of atom or group transfer radical polymerization for the synthesis of a ma

Abstract: Catalyst systems comprising, on the one hand, a catalytic solid based on complexed titanium trichloride and, on the other hand, a nonhalogenated organoaluminium activator. When employed in gas phase olefin polymerisation processes, these catalyst systems make it possible to manufacture a wide range of homopolymers and copolymers (random and block) with an isotacticity index which can be adjusted to very low values and with excellent pourability, even in the case of copolymers of high comonomer content. In the absence of transfer agents they also make it possible to synthesize polymers of very high molecular masses, with an increased activity. These polymerization processes yield particularly advantageous results in the case of propylene.

Abstract: A process for continuously producing a propylene-based block copolymer having an excellent impact resistance of the present invention, comprises:a first polymerization step comprising polymerizing .alpha.-olefin comprising propylene in the presence of hydrogen and a stereoregular polymerization catalyst comprising a solid catalyst component containing magnesium, titanium, halogen atom and an electron-donor compound, an organoaluminum compound and, if required, an electron-donar compound in a single polymerization reactor; anda second polymerization step comprising transporting .alpha.-olefin polymer obtained in the first polymerization step to a copolymerization reactor and copolymerizing propylene with .alpha.-olefin other than propylene in a gas phase substantially in the presence of said stereoregular polymerization catalyst used in the first polymerization step.

Abstract: A continuous process for preparation of propylene-ethylene block copolymer suitable for moldings with high rigidity and high impact resistance are provided, which process is a continuous process for preparation of highly rigid propylene-ethylene block copolymers, wherein propylene and ethylene are polymerized in the specified 2 steps with use of a catalyst system comprising (A) a solid catalyst component containing Ti, Mg, halogen and polyvalent carboxylic ester, (B) an organic aluminium compound, as well as (C) an organic silicon compound expressed by the general formula R.sup.4.sub.x R.sup.5.sub.y Si(OR.sup.6).sub.z (wherein, x+y+z=4), and wherein the ratio between the maximum value and the minimum value of MFR(l)) is0.1.ltoreq.Log(MFR(h)/MFR(l)).ltoreq.1,and the ratio between the average MFR(i) and MFR(ii) in the subsequent polymerization procedure (II) containing ethylene in a relatively large amount which is carried out by adding the glycol type compound is3.ltoreq.Log(MFR(i)/MFR(ii)).ltoreq.7.

Abstract: A process for preparing an olefin polymer comprising the steps of: preparing an olefin polymer ?I! by polymerizing or copolymerizing an olefin in the presence of an olefin poymerization catalyst comprising a specific solid titanium catalyst component ?A!, a specific organoaluminum compound catalyst component ?B! and a specific electron donor catalyst component ?C!; preparing an olefin polymer ?II! by polymerizing or copolymerizing an olefin in an polymerizer different from that for the polymerization of the above step in the presence of an olefin poymerization catalyst comprising a specific solid titanium catalyst component ?A!, a specific organoaluminum compound catalyst component ?B! and a specific electron donor catalyst component ?D!; and then allowing the resulting olefin polymer ?I! and the resulting olefin polymer ?II! to coexist in one polymerizer to further polymerize or copolymerize an olefin.

Abstract: A propylene block copolymer comprising a matrix phase and a dispersed phase dispersed in said matrix phase, said matrix phase comprising (a) polypropylene; said dispersed phase having an average particle diameter of from 0.1 to 5 .mu.m; and said dispersed phase comprising an outer layer comprising (b) propylene-.alpha.-olefin copolymer rubber and an inner layer comprising (c) crystalline polyethylene dispersed therein a plurality of particles comprising an outer layer comprising (b') propylene-.alpha.-olefin copolymer rubber and an inner layer comprising (a') polypropylene, a propylene block copolymer comprising a matrix phase and a dispersed phase dispersed in said matrix phase, said matrix phase comprising (a) polypropylene; said dispersed phase having an average particle diameter of from 0.1 to 5 .mu.m; and said dispersed phase comprising (b) propylene-.alpha.

Abstract: This invention relates to block polymers containing both crystalline and elastomeric blocks, the block copolymer having an A block and a B block. The A block is a polyethylene or an ethylene polymer optionally containing an alpha-olefin and optionally a non-conjugated diene, and is generally crystalline. The B block is an ethylene, .alpha.-olefin copolymer. Also disclosed is a process for manufacture of the block copolymers and methods for coupling the block copolymers. Coupled block copolymers are useful as thermoplastic elastomers exhibiting physical properties approaching those of crosslinked EP or EPDM elastomers, but showing thermal processability after coupling. The block copolymers of the present invention may also be used as a lubricant or fuel additive, as a plastics blend component, and as a component in hot melt adhesives.

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.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: A process for preparing a propylene polymer composition having excellent rigidity, heat resistance and impact resistance comprising conducting multistage polymerization including a step (a) for preparing a propylene (co)polymer (A), a step (b) for preparing a propylene-olefin copolymer (B) and a step (c) for preparing an ethylene-olefin copolymer (C) in the presence of (I) a transition metal compound and (II) a compound activating the transition metal compound (I), in which the steps (a), (b) and (c) are carried out in any order, each of the second and subsequent stage polymerizations is carried out in the presence of a polymer or polymers obtained by the preceding stage or stages, respectively, and the resulting propylene polymer composition contains the propylene (co)polymer (A) in an amount of 20 to 90% by weight, the propylene-olefin copolymer (B) in an amount of 5 to 75% by weight and the ethylene-olefin copolymer (C) in an amount of 5 to 75% by weight, and has MFR, as measured at 230.degree. C.

Abstract: A free radical polymerization process for the preparation of a polymer comprising heating a mixture of a free radical initiator, a stable free radical agent, a metal catalyst, or a metal stable free radical complex catalyst, and at least one polymerizable monomer; cooling said mixture; and optionally isolating said polymer.

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: A sheet such as a geomembrane consisting essentially of an extruded in situ blend of two copolymers of ethylene and one or more alpha-olefins having 3 to 8 carbon atoms, said blend having a flow index in the range of about 3 to about 100 grams per 10 minutes; a melt flow ratio in the range of about 50 to about 200; a density in the range of 0.905 to 0.943 gram per cubic centimeter; an Mw/Mn ratio in the range of about 10 to about 50; and a weight average molecular weight in the range of about 180,000 to about 465,000.

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: 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: An ethylene polymer which is useful for molding inflation film having a particularly excellent moldability is provided.The ethylene polymer is obtainable by the first and second steps and satisfying the following conditions (a) to (d):(a) the polymer produced in the first polymerization step having an weight average molecular weight (Mw,.sub.1) in the range of 6.times.10.sup.5 to 4.times.10.sup.6 ;(b) the ratio (Mw,.sub.2 /Mw,.sub.1) of the weight average molecular weight of the polymer produced in the first polymerization step (Mw,.sub.1) and the weight average molecular weight of the polymer produced in the second polymerization step (Mw,.sub.2) being in the range of 0.7 to 1.4;(c) the molecular weight in which the integration fraction from the low molecular weight is equal to 1/2 of the weight fraction (W.sub.2) of the polymer produced in the second polymerization step being in the range of 5.times.10.sup.3 to 3.times.10.sup.4 ; and(d) the weight fraction (W.sub.

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: A gas phase process for the production of an in situ polyethylene blend comprising contacting ethylene and at least one alpha-olefin comonomer having 3 to 8 carbon atoms with a magnesium/titanium based catalyst system including an activator and a cocatalyst in each of two fluidized bed reactors corrected in series, under polymerization conditions, with the provisos that:(a) the mixture of ethylene copolymer matrix and active catalyst formed in the first reactor in the series is transferred to the second reactor in the series;(b) other than the active catalyst referred to in proviso (a) and the cocatalyst referred to in proviso (f), no additional catalyst is introduced into the second reactor;(c) in the first reactor in which a relatively high molecular weight copolymer is made:(1) the alpha-olefin is present in a ratio of about 0.01 to about 0.4 mole of alpha-olefin per mole of ethylene; and(2) optionally, hydrogen is present in a ratio of about 0.001 to about 0.

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: A process comprising contacting ethylene and at least one alpha-olefin comonomer having 3 to 8 carbon atoms with a transition metal based catalyst system in two fluidized bed reactors connected in series, in the gas phase, under polymerization conditions, with the provisos that:(a) the first reactor is operated at a temperature at or above the dew point of the mixture of monomers, but no higher than about 5 degrees C. above said dew point;(b) the mixture of ethylene copolymer matrix and active catalyst formed in the first reactor in the series is transferred to the second reactor in the series;(c) other than the active catalyst referred to in proviso (b), no additional catalyst is introduced into the second reactor;(d) in the reactor in which a low melt index copolymer is made:(1) the alpha-olefin is present in a ratio of about 0.01 to about 0.4 mol of alpha-olefin per mol of ethylene; and(2) optionally, hydrogen is present in a ratio of about 0.001 to about 0.

Abstract: Multistage process for the polymerization of one or more olefins of the formula CH.sub.2 .dbd.CHR, in which R is hydrogen or an alkyl, cycloalkyl or aryl group having from 1 to 10 carbon atoms, comprising:(A) a first stage of polymerization, in which a first olefin polymer is prepared in the presence of titanium catalyst or vanadium catalyst;(B) a treatment stage in which the catalyst used previously is deactivated and in which a metallocene compound is supported on the olefin polymer produced in stage (A); and(C) a second stage of polymerization in which one or more olefins are polymerized in the presence of the product obtained from stage (B).

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: A propylene block copolymer having a high impact resistance is prepared without the generation of finely divided particles or the adhesion to the reactor, which propylene block copolymer having a weight ratio of 5/95-70/30 (process (1)/process (2)) is obtained by carrying out the particular polymerization processes (1) and (2) in this sequence under the action of the catalyst comprising the following A and B.A: particular transition metal compound.B: an alumoxane, the reaction product of an alkylboronic acid with an organoAl, a Lewis acid or ionic compound.Process (1): process for copolymerizing propylene and a specified comonomer in a ratio of 0/100-80/20.Process (2): process for producing a propylene polymer having a specified comonomer in an amount of 10% by weight or less.

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: Seeded cation-exchange resin beads are particularly susceptible to oxidative degradation which results in the leaching of organic carbon fragments. The leachability of organic carbon fragments of molecular weights greater than 1000 g/mol is reduced to less than 800 ppm by effectively crosslinking the copolymers that comprise the seeded cation-exchange resin beads. Crosslinking can be achieved either during sulfonation by increasing sulfone bridge formation or before sulfonation by either alkylene bridge formation or by incorporation and subsequent activation of a crosslinkable functionality in the copolymer that forms the seed in the seeded polymer bead process.

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: In accordance with the present invention, there is provided a method for the preparation of an ethylene polymer composition having a density of 0.86-0.94 g/cm.sup.3 and an intrinsic viscosity [.eta.] of 1-6 dl/g using an olefin polymerization catalyst composed of a transition metal compound containing a ligand having a cycloalkadienyl skeleton and an organoaluminium oxy-compound, and there is also provided a method for the preparation of an ethylene polymer composition having density of 0.87-0.93 g/cm3 and an intrinsic viscosity [.eta.] of 0.5-6 dl/g.

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: Multistage process for the polymerization of olefins CH.sub.2 .dbd.CHR, where R is hydrogen or an alkyl, cycloalkyl or aryl radical with 1-10 carbon atoms, comprising two stages of polymerization. In a first stage, in the presence of a titanium or a vanadium catalyst and working in one or more reactors, an olefinic polymer with particular values of porosity is prepared; in a second stage, in the presence of the said porous polymer and a metallocene compound and/or their reaction products, one or more olefins, that are equal to or different from those polymerized in the first stage, are polymerized in one or more reactors.

Abstract: There are disclosed a styrenic copolymer which comprises at least one structural unit represented by the general formula (I) ##STR1## and a structural unit represented by the general formula (II) ##STR2## or a structural unit represented by the general formula (IX) ##STR3## wherein the symbols are each as previously defined in the specification, the structural unit (II) or (IX) being contained in an amount of 0.01 to 99.9 mol %; and a process for the production of the above copolymer.The above styrenic copolymer has a high degree of syndiotactic configuration in the stereoregularity of the main chain of the structural unit (I) as well as adhesivity and compatibility with a resin of a different type.

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: Propylene polymers have a molecular weight ratio Q (M.sub.w /M.sub.n) of from 6 to 30 and are obtainable by Ziegler-Natta polymerization in the presence of hydrogen as molecular weight regulator and are particularly suitable for the production of films and moldings.

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.