Abstract: A method of terminating a living polymer comprising the step of reacting with a living polymer a terminator defined according to formula (I) ##STR1## where Z is a halogen atom; R.sub.1 is selected from the group consisting of organic groups containing from 1 to about 12 carbon atoms and a bridging bond; each R.sub.2 is independently selected from the group consisting of hydrogen, organic groups containing from 1 to about 12 carbon atoms, and a bridging bond; each R.sub.3 is independently selected from the group consisting of hydrogen and organic groups containing from 1 to about 12 carbon atoms; a is an integer from 4 to about 16; and b is an integer from 0 to about 12; and optionally including a bridge, formed by the selection of two of said bridging bonds, the bridge having 0 to about 6 carbon atoms between the bridging ring members. Also provided are a vulcanizable composition of matter, a vulcanizate and a tire comprising the functionalized polymers of the present invention.

Abstract: There is provided a method for terminating a gas phase polymerization of a compound selected from the group consisting of a conjugated diene, a vinyl-substituted aromatic compound, and mixtures thereof, in a polymerization vessel in the presence of a catalyst, and optionally in the presence of an inert particulate material, comprising introducing a kill agent selected from the group consisting of an alcohol having 1 to 20 carbon atoms, an alkyl or cycloalkyl monoether, ammonia, water, an alkyl or aryl amine, and mixtures thereof.

Abstract: The present invention provides a method of anionic synthesis of stable macrocyclic polymers that are compounded to form vulcanizable elastomeric compounds exhibiting reduced hysteresis properties. Cyclic organometallic compounds containing divalent metal atoms of Groups IIA and IIB of the Periodic System are employed as initiators of anionic polymerization of conjugated diene, vinyl aromatic and/or triene monomers. Coupling of the living ends of the resulting macrocyclic polymers or copolymers with a coupling agent or a coupling agent that is also a functionalizing agent results in stable macrocyclic polymers with improved hysteresis properties.

Abstract: The invention is a practical process for anionically synthesizing commercially significant quantities of macrocyclic polymers from polar and/or non-polar monomers by using Group IIA and IIB metal cyclic organometallic initiators. Activation of the ring metal atom results in anionic polymerization of the monomers by addition into the initiator ring at the bonds between the atom and its two adjacent carbon atoms, the metal atom acting as a bridge between the two living ends of the propagating chain. Coupling of the cyclic polymer living ends by coupling agents produces macrocyclic polymers that are stable in air and moisture and that exhibit desirable properties, such as low viscosities at high molecular weights. Such macrocyclic polymers provide enhanced polymer processability during molding, extruding and the forming of films.

Abstract: There is disclosed a method for synthesizing polyolefins having a silyl group at one terminus, said method comprising reacting(A) a monomer selected from the group consisting of ethylene and a combination of ethylene and an .alpha.-olefin; and(B) a silane having the formulaR.sup.2 R.sup.3 R.sup.4 SiHwherein R.sup.2, R.sup.3 and R.sup.4 each represents a monovalent group selected from the group consisting of hydrogen, alkyl having 1 to 4 carbon atoms, aryl, alkylaryl, arylalkyl, alkoxy having 1-4 carbon atoms, phenoxy, fluorinated alkyl having 3 to 6 carbon atoms, a dialkylamino group in which the alkyl groups contain 1 to 4 carbon atoms and a diorganopolysiloxane chain containing 1 to 10 siloxane units, said reaction taking place in the presence of(C) a catalyst comprising a metallocene compound.

Abstract: Addition polymers derived from norbornene-functional monomers are terminated with an olefinic moiety derived from a chain transfer agent selected from a compound having a terminal olefinic double bond between adjacent carbon atoms, excluding styrenes, vinyl ethers, and conjugated dienes and at least one of said carbon atoms has two hydrogen atoms attached thereto. The addition polymers of this invention are prepared from a single or multicomponent catalyst system including a Group VIII metal ion source. The catalyst systems are unique in that they catalyze the insertion of the chain transfer agent exclusively at a terminal end of the polymer chain.

Abstract: Addition polymers derived from norbornene-functional monomers are terminated with an olefinic moiety derived from a chain transfer agent selected from a compound having a terminal olefinic double bond between adjacent carbon atoms, excluding styrenes, vinyl ethers, and conjugated dienes and at least one of said carbon atoms has two hydrogen atoms attached thereto. The addition polymers of this invention are prepared from a single or multicomponent catalyst system including a Group VIII metal ion source. The catalyst systems are unique in that they catalyze the insertion of the chain transfer agent exclusively at a terminal end of the polymer chain.

Abstract: A process comprising contacting propylene in two reaction zones connected in series, under gas phase polymerization conditions, with a transition metal catalyst system comprising(a) introducing the catalyst into the first reaction zone;(b) partially deactivating the catalyst and simultaneously increasing the monomer level to achieve a desired resin productivity in the first zone; and(c) transferring resin together with catalyst from the first zone to the second zone having purged the deactivator or added activator in sufficient amount to achieve a desired resin productivity in the second zone.

Abstract: Method for the shortstopping of polymerizations of conjugated dienes possibly mixed with vinyl-substituted aromatic products in a radicalic emulsion polymerization process using a redox initiator, in particular radicalic emulsion polymerizations of butadiene possibly mixed with styrene or acrylonitrile, a method which enables the production of polymers without nitrosamines (NA) and/or their precursors.

Abstract: Described is the use of physiologically compatible tocopherols and especially of vitamin E as an inhibitor against premature polymerization initiation in reactive systems capable of undergoing a free radical-initiated polymerization, which systems before and/or after the polymerization thereof are placed in tissue contact with the living human or animal body and, more specifically, are implanted into the living organism thereby. The reactive systems and the polymers formed therefrom may be degradation resistant. However, a special embodiment relates to compositions or molded bodies which are decomposed by the living organism, and especially so under time-controlled conditions.

Abstract: The temperature of the polymerization medium of vinyl chloride with the involvement of oil-soluble initiators is controlled essentially by direct and modified injection of an effective amount of a strong inorganic inhibitor of radical polymerization or of a precursor advantageously chosen from iodine and nitrogen monoxide, as well as from alkali metal iodides and nitrites, which are the respective precursors of iodine and of nitrogen monoxide.

Abstract: An aminated polymer having excellent adhesion, printability, and compatibility in polymer blends or the like which are obtained by introducing an amino group, into an isotactic .alpha.-olefin polymer having an olefinic unsaturated bond at its terminus is disclosed. The terminal unsaturated isotactic or syndiotactic .alpha.-olefin polymer is obtained by polymerizing an .alpha.-olefin with a catalyst comprising the combination of a metallocene compound and an alumoxane, and the amino group is obtained by the amination of the terminal unsaturated group, by the addition of a compound containing the corresponding functional group to the unsaturated bond, or by the conversion of a precursor polymer containing a precursor of the functional group into a polymer containing the functional group desired.

Abstract: A process for preparing olefinic polymers by metallocene catalyzed olefin polymerisation in which at least one volatile catalyst kill agent is introduced. A non-volatile catalyst kill agent may also be used in conjunction with the volatile catalyst kill agent. Water may be used as the volatile agent and compounds containing a terminal hydroxy group, oxygen, nitrogen or sulfur may constitute the non-volatile agent. Purified monomer is recycled to the reactor.

Abstract: The present invention relates to a method of terminating a free radical initiated emulsion polymerization by using a shortstopping agent selected from the group consisting of isopropylhydroxylamine and salts thereof. One advantage in using these shortstopping agents is these shortstopping agents do not contribute to the generation of volatile nitrosamines.

Abstract: The present invention relates to a process for stopping an olefin polymerization which is carried out in a low pressure gas phase reactor, which process comprises introducing an effective quantity of deactivating agent into the reactor, characterized in that the olefin polymerisation is carried out using a chromium oxide catalyst and in that the deactivating agent is selected from oxygen, ammonia, water and carbon monoxide and is introduced over a relatively short period of time. The deactivating agent is preferably introduced into the polymerization reactor in a quantity such that in the reactor the weight ratio of the deactivating agent to the catalyst is at least 0.001.

Abstract: A process for stabilizing an ethylenically unsaturated monomer or oligomer from premature polymerization is disclosed whereby a stabilizing amount of an N-hydroxy substituted hindered amine is added to said polymerizable monomer or oligomer. The ethylenically unsaturated monomer or oligomer encompass vinyl monomers or oligomers bearing at least one polymerizable moiety. The N-hydroxy substituted hindered amine inhibits premature polymerization in the liquid and/or vapor phase.

Abstract: A process for emulsion polymerization to form a latex having a particle size greater than about 0.5 micrometers by charging to a reaction vessel under agitation a reaction mixture including water, emulsifiers at an initial concentration slightly greater than or equal to the critical micelle concentration, a protective colloid, ethylenically unsaturated monomers, and an ionically balanced combination of an anionic and a cationic water soluble free radical initiator or a nonionic initiator; reacting the mixture to form an emulsion of polymerized monomer; and adding additional monomer, emulsifier, and protective colloid and a water soluble chain transfer agent to the reactor while continuing to agitate the mixture under conditions such that the emulsifier concentration does not exceed that at which new polymeric nuclei are formed.

Abstract: A process for preparing a vinyl chloride polymer, which comprises polymerizing vinyl chloride or a monomeric mixture composed mainly of vinyl chloride in an aqueous medium, wherein the polymerization reaction is terminated at the last stage of polymerization by addition of an aqueous dispersion of an antioxidant, containing a polyoxyalkylene glycol as a dispersing agent. A polymer with good initial coloration characteristic, thermal stability and take-up of plasticizer, and large bulk density can be obtained.

Abstract: This is an improvement upon a process which comprises anionically polymerizing monomers with an anionic polymerization initiator in a suitable solvent thereby creating a living polymer. The improvement comprises terminating the polymerization by the addition of a terminating agent selected from the group consisting of boranes, ammonia, halogens, hydrocarbons containing a C-H group where the carbon is connected directly to a triply-bound carbon or to two doubly-bound carbons and silanes.

Abstract: A process for the continuous polymerization of one or more alpha-olefins with a transition metal catalyst, in a reactor having a fluidized and/or mechanically stirred bed, in which a very small amount of an activity retarder, generally less than 0.1 ppm, is introduced continuously into the reactor at a flow rate which is varied with time so as to keep substantially constant either the polymerization rate or the content of transition metal in the polymer produced. Suitable activity retarders include polymerization inhibitors such as, for example, oxygen, alcohols, carbon monoxide and carbon dioxide and electron donor compounds such as amides and ethers.

Abstract: By a process for suspension polymerization, which comprises steps of:supplying a slurry comprising droplets of a monomer liquid having a substantially uniform size dispersed in an aqueous dispersion medium to a tower type reactor in which said medium forms a downflow, andsuspension polymerizing the monomer with avoiding merging or splitting of the droplets in a fluidized bed which is formed by the downflow of said medium and buoyancy of the monomer liquid droplets, whereinthe specific gravity of said medium is made larger than that of a polymer particle to be produced by the addition of a water soluble inorganic salt to said medium, anda polycarboxylic acid type anionic polymeric surfactant is used as a suspension stabilizer for the monomer liquid droplets,polymer particles having a substantially uniform size are produced with high polymerization conversion.

Abstract: A bromostyrene composition having overcome the unstability of bromostyrenes and being stable at the time of its storage and transportation is provided, which composition comprises 100 parts by weight of a styrene substituted with one, two or three bromine atoms on the benzene nucleus thereof or a mixture of the foregoing, 20 to 3,000 parts by weight of an aromatic vinyl compound such as styrene and 0.001 to 0.05 part by weight of a polymerization inhibitor.

Abstract: Coupling agents of general formula ##STR1## and their use in a method for the termination of living polymers obtained by the anionic polymerization of dienic and/or vinylaromatic monomers.

Abstract: A suspending agent system, a polymerizable reaction mixture, and a polymerization reaction process for producing high bulk density resin on a consistent basis by incorporating in the reaction mixture prior to initiation of the reaction about 1-250 parts per million by weight of polymerization inhibitor and also including about 0.001-0.1 parts by weight based on the weight of VCM of a highly hydrolyzed PVA. Preferred PVA's have a 4 weight percent aqueous solution viscosity of 30-100 centipoise and an effective polymerization inhibitor is diethylhydroxylamine. Bulk densities may be increased from about 3-10% depending upon the size of the reaction and the particular ingredients chosen.

Abstract: Coupling agents of general formula ##STR1## and their use in a method for the termination of living polymers obtained by anionic polymerization of diene and/or vinylaromatic monomers.

Abstract: Coupling agents of general formula ##STR1## and their use in a method for the termination of living polymers obtained by the anionic polymerization of dienic and/or vinylaromatic monomers.

Abstract: Coupling agents of general formula ##STR1## and their use in a method for the termination of living polymers obtained by the anionic polymerization of dienic and/or vinylaromatic monomers.

Abstract: In a process for the mass polymerization of vinyl aromatic monomer wherein vinyl aromatic monomer is polymerized in successive stages of increasing temperature, the improvement which narrows the molecular weight distribution of the resulting polymer comprising incorporating a polymerization inhibiting agent into a polymerizing mass at a point where about 60 to about 95% of monomer is converted to polymer.

Abstract: A solution polymerization process for the preparation of high molecular weight polymers of alpha-olefins selected from the group consisting of homopolymers of ethylene and copolymers of ethylene and C.sub.4 -C.sub.12 alpha-olefins is disclosed. The process comprises feeding monomer(s), coordination catalyst and inert hydrocarbon solvent to a reactor, polymerizing the monomers at a temperature of up to 320.degree. C. and a pressure of less than 25 MPa, and deactivating the catalyst in the solution so obtained. The catalyst is deactivated by sequentially admixing therewith a minor amount of a nitrogenous base, especially an aqueous solution of such a base, followed by a solution of a salt of an alkaline earth metal or zinc and an aliphatic monocarboxylic acid dissolved in hydrocarbon solvent. The ratio of water:nitrogenous base should not be greater than 5.

Abstract: The process, which comprises a first stage for (co)polymerizing ethylene at 180.degree.-320.degree. C. and 300-2,500 bars in the presence of a Ziegler type catalytic system, a second stage for separation, a third stage for recycling unreacted monomers, and a fourth, recompression stage, is characterized by introducing into the stream of recycled monomer(s) during the third stage, at least one compound selected from the amides of the saturated or unsaturated organic acids containing from 12 to 22 carbon atoms, polyalkylene polyols containing from 4 to 500 carbon atoms, and compounds containing at least two epoxide functions, with a molecular weight greater than approximately 200. Preferably from 0.005 to 0.1 mole of the selected compound is introduced per ton of recycled monomer.This process makes it possible to avoid the formation of high molecular weight polymers in the recycle circuits.

Abstract: An improved method of terminating ethylene polymerization and interpolymerization reactions by deactivating the Ziegler-type catalyst used in the reaction comprises the step of injecting a selected deactivating agent into the molten polymer solution in the polymerization reactor prior to degassing of the polymer solution.The deactivating agent is selected from the group consisting of:(a) natural hydrotalcite minerals and synthetic hydrotalcite-like materials;(b) Group IIIA metal salts of monocarboxylic acids;(c) alkali metal and alkaline earth metal salts of alkarylsulfonic acids;(d) alkali metal and alkaline earth metal salts of alkyl and alkaryl sulfuric acids;(e) organophosphites of a formula selected from the group consisting of (RO).sub.3 P and (RO).sub.2 POH where R is a hydrocarbon group containing 1 to 22 carbon atoms, inclusive;(f) ethoxylated hydrocarbylamines of the formula R'.sub.3-n N[(OCH.sub.2 CH.sub.2).sub.m OH].sub.

Abstract: Coupling agents of general formula ##STR1## and their use in a method for the termination of living polymers obtained by anionic polymerization of diene and/or vinylaromatic monomers.

Abstract: Photopolymerizable water-soluble or water-dispersible mixtures essentially consist of a base polymer, at least one polymerizable ethylenically unsaturated compound, at least one photoinitiator and/or photosensitizer and at least one stabilizer, the thermal polymerization inhibitor being a water-soluble salt of nitrous acid.

Abstract: A process for preventing the formation of polymeric by-products during the production of Diels-Alder adducts is improved by the addition of NO or of a compound splitting off NO in situ, as a polymerization inhibitor. This process is especially effective for preventing the formation of polymeric by-products in the manufacture of 5-vinylnorbornene-2. In a tubular reactor, when observing narrow temperature and pressure ranges, a high selectivity is obtained in the production of this adduct.

Abstract: An improved process for terminating the suspension polymerization reaction of vinyl chloride monomer into polyvinyl chloride which comprises adding hindered phenols of the structure presented hereinafter to the polymerization reaction at a point in time when a predetermined amount of monomer conversion has occurred.

Abstract: A compound and a process for utilizing the compound to prevent the polymerization of vinyl aromatic compounds, such as styrene, during heating. The composition includes effective amounts of 2,6-dinitro-p-cresol and either a phenylenediamine or 4-tert-butylcatechol respectively, to act as a polymerization co-inhibitor system in the presence of oxygen.

Abstract: A compound and a process for utilizing the compound to prevent the polymerization of vinyl aromatic compounds, such as styrene, during heating. The compound includes effective amounts of phenothiazine, 4-tert-butylcatechol and 2,6-dinitro-p-cresol respectively, as a polymerization inhibitor system in the presence of oxygen resulting in a less viscous polymer tar and in the effective inhibition of polymerization to temperatures as high as 150.degree. C.

Abstract: A compound and a process for utilizing the compound to prevent the polymerization of vinyl aromatic compounds, such as styrene, during heating. The composition includes effective amounts of 2,6-dinitro-p-cresol and either a phenylenediamine or 4-tert-butylcatechol respectively, to act as a polymerization co-inhibitor system in the presence of oxygen.

Abstract: A method for stopping and restarting the free-radical polymerization of vinyl monomers (e.g. acrylic monomers) without forming low molecular weight polymer is provided. These polymerizations utilize a Redox catalyst system comprising multivalent metal ions (e.g. iron ions) as promoter. The polymerizations are stopped by chelation of the iron present. Additional monomer is added to the polymerization to avoid formation of low molecular weight polymer. Upon restart metal ions are added to the polymerization mixture.

Abstract: The present invention is an improved polymerization process which comprises polymerizing isoprene under solution polymerization conditions in a hydrocarbon solvent with a catalyst system comprising a mixture of titanium tetrachloride and a trialkylaluminum compound, wherein the polymerization is shortstopped with 4,7-diaza-decane-1,10-diamine.

Abstract: The preparation of synthetic rubbers characterized by high green strength and tack in which a polymerizable unsaturated tertiary amine and a polymerizable cross linking agent in the form of an organic compound containing active halogen groups are copolymerized with the rubber forming monomers.

Abstract: By adding substances corresponding to the following general formula I ##STR1## in which X=O, S or N--R.sub.5 ; R.sub.1 =hydrogen, C.sub.1 -C.sub.19 -alkyl, C.sub.2 -C.sub.19 -alkenyl, phenyl, C.sub.1 -C.sub.4 -alkylene phenyl, C.sub.5 -C.sub.12 -cycloalkyl or C.sub.5 -C.sub.12 -cycloalkenyl; R.sub.2 =hydrogen, C.sub.1 -C.sub.19 -alkyl, C.sub.2 -C.sub.12 -alkenyl, phenyl or C.sub.1 -C.sub.4 -alkylene phenyl; R.sub.3 =hydrogen, C.sub.1 -C.sub.19 -alkyl, C.sub.2 -C.sub.19 -alkenyl, phenyl, C.sub.1 -C.sub.4 -alkylene phenyl, acryl formyl or acetyl; R.sub.4 and R.sub.5 =same or different, C.sub.1 -C.sub.19 -alkyl, C.sub.2 -C.sub.19 -alkenyl, phenyl, C.sub.1 -C.sub.4 -alkylene phenyl, acryl, C.sub.5 -C.sub.12 -cycloalkyl or C.sub.5 -C.sub.12 -cycloalkenyl; R.sub.4 and R.sub.5 may also form a C.sub.4 -C.sub.7 -ring which may optionally contain an oxygen atom in ether form and the radicals R.sub.1 and R.sub.2 may form a C.sub.5 -C.sub.12 -alkylene bridge or a C.sub.5 -C.sub.12 -alkenylene bridge, the radicals R.sub.

Abstract: A process for producing a paste-blending vinyl chloride resin, which comprisesinitiating suspension polymerization of a vinyl chloride monomer or a mixture of it with a monomer copolymerizable therewith in an aqueous medium in the presence of a water-soluble protein as a suspending agent;adding a proteolytic enzyme to the polymerization system at any point in a time period running from the time when the polymerization conversion reaches 10% by weight to the time when the polymerization reaction is not yet complete; andthereafter continuing the suspension polymerization until the polymerization reaction is completed.

Abstract: A heat-stable, polymer-forming composition of a polymerizable material, a transition metal compound, a polymer chain terminator, and, optionally, a preventive antioxidant is disclosed as well as particular uses of such composition.

Abstract: Process for rapidly terminating the polymerization of vinyl chloride in aqueous suspension in the presence of lower dialkyl peroxydicarbonates by introducing effective amounts of ammonium hydroxide and an alkali metal thiosulphate, e.g. sodium or ammonium thiosulphate, into the polymerization medium. This process enables polymerization to be quickly and effectively terminated when a breakdown occurs.

Abstract: A process for preparing polytetrafluoroethylene fine powder by polymerization of tetrafluoroethylene in an aqueous medium comprising a water-soluble polymerization initiator and a non-telogenic surfactant capable of keeping colloidal polytetrafluoroethylene particles at a sufficiently stable state, characterized in that the polymerization is carried out at a temperature of 55.degree. to 120.degree. C., and a polymerization retarder chosen from aromatic hydroxy compounds, aromatic amino compounds and quinone compounds which has a water-solubility of not less than 2.5.times.10.sup.-6 mol/liter at 25.degree. C. and does not have any reinitiation ability after its addition or chain transfer to a free radical in the polymerization system is incorporated in the aqueous medium in an amount of 0.

Abstract: The present invention relates to the polymerization of vinyl monomers either alone or copolymerized with ethylenically unsaturated polymerizable monomers having a terminal CH.sub.2 .dbd.C< grouping using a free-radical yielding catalyst or catalyst system, wherein the polymerization reaction is effectively stopped by the addition to the reaction mixture of a shortstopping agent, such as, for example, 4,4'-thiodiphenol (TDP).

Abstract: A process is disclosed for preparing a polycloroprene elastomer consisting of a blend of from 20 to 80 parts by weight of (a) a toluene-insoluble gel polymer and from 80 to 20 parts by weight of (b) a toluene-soluble sol polymer, the process comprising preparing the toluene-insoluble gel polymer by polymerizing chloroprene or a mixture of chloroprene with a small amount of at least one copolymerizable monomer in the presence of a suitable cross-linking agent, preparing the toluene-soluble sol polymer by polymerizing chloroprene or a mixture of chloroprene with a small amount of at least one copolymerizable monomer and blending the gel and sol polymers wherein an improved elastomer is obtained by polymerizing the toluene-insoluble gel polymer to a cross-linking density of at least 2.4 .times. 10.sup.-6 to a monomer conversation of at least 80%.

Abstract: Esters of acrylic acid and methacrylic acid may be polymerized with the aid of either free radical forming or ionically effective initiators. The stereospecificy of the polymers may be influenced by the selection of specific initiators; magnesium-organic compounds are suitable for the synthesis of isotactic polymers. Acrylic acid and methacrylic acid esters having a high degree of isotacticity and a narrow molecular weight distribution are obtained with the aid of substituted phenylmagnesium halides. They are suitable as gauge and as test substances.

Abstract: A method is provided for the production of homogeneous copolymers from monomers having differing reaction rates; in particular copolymers of acrylonitrile or of vinylidene chloride are disclosed. The monomers are fed to the reaction mixture at a rate sufficient to maintain a constant monomer ratio in the reaction mixture throughout the course of the reaction, the rate of addition being determined by the rate of evolution of heat as measured by the rate that a cooling system removes heat evolved by the reaction. An injection-mouldable copolymer consisting essentially of acrylonitrile units and uniformly distributed units of styrene or .alpha.-methyl styrene may be produced in this way. Films of the copolymer can be oriented by stretching at 90.degree.-140.degree. C. Its softening point may be increased by copolymerizing a minor amount of N-aryl maleimide.