Abstract: A method for vapor phase polymerization comprises blowing a gaseous monomer from a bottom of a fluidized bed reactor through a distributor plate into the reactor by means of a blower while feeding a solid catalyst into the reactor to thereby form a fluidized bed in the reactor and conducting a vapor phase polymerization to produce a polymer or copolymer, wherein the blower has a slide or rotational slide part between its discharge side as a high pressure side and its suction side as a low pressure side in a blower body casing, said slide or rotational slide part being provided with a noncontacted gas leakproof seal part at a clearance ranging from 0.7 to 2.5 mm.

Abstract: The present invention is directed to a porous polymer micro-particle, in the form of broken spheres, open to a porous oleophilic interior surface area, having a high oil and water absorbency and an apparent bulk density of about 0.02 to about 0.1 grams/cc.

Abstract: The present invention provides a process for the production of a compound of formula: ##STR1## in which X and Y, independently, are hydrogen, halogen, NO.sub.2, CF.sub.3, CN, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, COO--C.sub.1 -C.sub.4 alkyl, CO--C.sub.1 -C.sub.4 alkyl, NH--(C.sub.1 -C.sub.4 alkyl), N(C.sub.1 -C.sub.4 alkyl).sub.2, NH(C.sub.1 -C.sub.4 alkyl-OH), N(C.sub.1 -C.sub.4 alkyl-OH).sub.2, COOH or SO.sub.3 H or an ester or amide thereof, or COOM or SO.sub.3 M in which M is Na, K, Ca, Mg, ammonium, mono-, di-, tri- or tetra-C.sub.1 -C.sub.4 alkylammonium, mono-, di- or tri-hydroxyalkylammonium or ammonium that is di- or tri-substituted with a mixture of C.sub.1 -C.sub.4 alkyl and C.sub.1 -C.sub.4 hydroxyalkyl groups;Z is hydrogen, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, CF.sub.3, halogen (F, Cl, Br, I), SO.sub.3 H or SO.sub.

Abstract: For gas phase polymerization reactions in the presence of an unsupported polymerization catalyst, there is provided a process for introducing a liquid catalyst so as to provide a resin particle lean zone such that the average particle size of the resin produced ranges from about 0.01 to about 0.06 inches.

Abstract: A process for discharging a reactor characterized by reducing the volume of a powder without compacting it, including treating the powder in a densification zone including at least one Archimedes' screw arranged in a barrel. The Archimedes' screw may also have both a reduction in pitch and an increase in diameter of the shaft. The densification zone may also contain two co- or counterrotating screws arranged in a barrel and exhibiting a reduction in the pitch of the screws. Densification zones consisting of two co-rotating screws give particularly good results.

Abstract: A photo-curable resin composition suitable as a material for photo-fabricating and capable of producing cured products with excellent mechanical strength and high heat resistance. Further disclosed is a process for molding a resin-based mold which provides superior molding dimensional precision and superb repetition durability. The resin composition contains a monomer component containing (A) 30-70 wt % of a polyfunctional unsaturated monomer having a cyclic structure and (B) 70-30 wt % of a monofunctional unsaturated monomer having a cyclic structure of which the homopolymer has a glass transition temperature (Tg) of 70.degree. C. or higher; (C) a photo-initiator; and (D) an inorganic filler having an average particle diameter or an average fiber length of 1-50 .mu.

Abstract: The present invention relates to a process for continuous gas-phase polymerisation of olefin(s) in a fluidized-bed reactor, comprising drawing off the polymer from the vertical side wall of the reactor into a lock hopper via a draw-off conduit so that all flow of the polymer in the draw-off conduit is produced according to a downward direction forming with a horizontal plane an inclination with an angle A at least equal to the angle of repose .beta. of the polymer and not exceeding 90.degree.. The present invention improves the degree of filling of the lock hopper and reduces the amount of gas drawn off with the polymer.

Abstract: The present invention relates to a process for introducing a solid catalyst into a gas-phase olefin polymerization reactor. It comprises in particular storing the catalyst in the form of a dry powder in a hopper, withdrawing from the hopper a measured amount of the said catalyst, introducing the said amount of the catalyst and a liquid hydrocarbon into a mixing chamber, mixing the said catalyst with the said liquid hydrocarbon so as to form in the said chamber a suspension of the entrained catalyst with the said liquid hydrocarbon, and introducing the said suspension into the said reactor. In a preferred form, the liquid hydrocarbon is continuously introduced into the chamber and forms a continuous stream to which is added the measured amount of the catalyst and which flows into the reactor.

Abstract: A improved process is provided for polymerization of olefin and/or diolefin polymer, using sonic cleaning devices, with optimum design and operation, to eliminate or reduce reactor fouling and/or sheeting.

Abstract: In a process for preparing polystyrene by continuous anionic polymerization of styrene monomer by means of a catalyst based on a metal alkyl preferably in the presence of a solvent at a temperature in the range from 30 to 70.degree. C., the styrene monomer is fed to an essentially isothermally operated circulation reactor configured as a closed tube loop which has, for example, a specific cooling area of at least 50 m.sup.2 per m.sup.3 of reactor volume, with the circulation velocity of the reaction mixture and the residence time being set such that the monomer conversion reaches at least 50% and the polymerization is completed in an essentially backmixing-free tube reactor.

Abstract: The present invention provides a continuous gas fluidised bed process for the polymerisation of olefin monomer selected from (a) ethylene, (b) propylene, (c) mixtures of ethylene and propylene, and (d) one or more other alpha-olefins mixed with (a), (b) or (c), to produce a polymer in a fluidised bed reactor which process comprises:(a) continuously withdrawing from the reactor a gaseous stream comprising unreacted olefin monomer and having entrained therein catalyst and/or polymer particles;(b) continuously recycling said gaseous stream comprising unreacted olefin monomer through a fluidised bed in said reactor in the presence of a polymerisation catalyst under reactive conditions;(c) cooling by means of heat exchanger(s) at least part of said gaseous stream withdrawn from said reactor to a temperature at which liquid condenses out;(d) separating at least part of the condensed liquid from the gaseous stream; and(e) introducing at least part of the separated liquid directly into the fluidised bed, characterise

Abstract: In gas phase polymerizations and copolymerizations of ethylene, reagents or cofeeds control the molecular weight, expressed as MI (wherein MI is measured according to ASTM D-1238 Condition E), of the resin product. Use of isopentane and electron donating compounds decrease MI; whereas, electron withdrawing compounds increase MI.

Abstract: Novel catalysts are provided for the polymerization of olefins such as ethylene. These catalysts comprise a novel amorphous aluminophosphate comprising, on a microlevel, sheets of aluminophosphate as well as spheres of aluminophosphate plus a chromium compound. These new catalysts are surprisingly active; result in more co-monomer incorporation than prior art catalysts and reduce the amount of low molecular weight material in the product.

Abstract: By utilizing the vapor phase polymerization techniques of the present invention, numerous distinct and highly beneficial advantages are realized. For instance, cis-1,4-polyisoprene rubber and high cis-1,4-polybutadiene rubber having a consistent and controllable molecular weight can be easily and practically prepared without utilizing a solvent. The subject invention more specifically discloses a method for vapor phase polymerizing isoprene into cis-1,4-polyisoprene in a process comprising the steps of:(1) charging into a reaction zone said isoprene and a preformed catalyst system which is made by reacting an organoaluminum compound with titanium tetrachloride, preferably in the presence of at least one ether; wherein the isoprene is maintained in the vapor phase in said reaction zone by a suitable combination of temperature and pressure;(2) allowing said isoprene to polymerize into cis-1,4-polyisoprene in said reaction zone at a temperature within the range of about 0.degree. C. to about 100.degree. C.

Abstract: A process for the gas phase polymerization of olefins. In this process a transition metal-containing solid catalyst component is introduced into a cylindrical section of a vertically disposed reactor in a first stream. A second stream, comprising an organometallic cocatalyst component is simultaneously separately introduced into the said cylindrical section of a vertically disposed reactor at a distance from the point of introduction of the first stream of no more than about 20% of the inside diameter of the tubular reactor.

Abstract: Disclosed is a process for the preparation of a polymer which comprises effecting bulk polymerization of a mixture of at least one monomer, a free radical polymerization initiator, and a stable free radical agent until from about 10 to about 50 weight percent of the monomer has been polymerized; optionally adding additional free radical initiator; optionally adding a colorant; dispersing with a high shear mixer the aforementioned partially polymerized mixture in water containing a stabilizing component selected from the group consisting of non-ionic and ionic water soluble polymeric stabilizers to obtain a suspension of particles with an average diameter of from about 0.1 to about 10 microns; polymerizing the resulting suspension to form said polymer.

Abstract: By utilizing the techniques of this invention, trans-1,4-polybutadiene can be synthesized continuously to a high level of conversion utilizing a low level of a highly active cobalt-based catalyst system. The trans-1,4-polybutadiene made with the cobalt-based catalyst system of this invention also typically has a molecular weight which is acceptable for use in tire applications without the need for employing a molecular weight regulator. It is also not typically necessary to utilize a gel inhibitor, such as carbon disulfide, in the polymerizations of this invention. Since a low level of residual cobalt is present in the trans-1,4-polybutadiene which is made utilizing the catalyst system of this invention, it is much more stable than trans-1,4-polybutadiene made with standard cobalt-based catalyst systems.

Abstract: A process for producing polymer in a gas phase reactor by introducing a stream of monomer and gas into a polymerization zone while providing at least one liquid component in the polymerization zone.

Abstract: The present invention provides a method of producing vinyl chloride polymers, including the steps of subjecting vinyl chloride monomer or a mixture of monomers containing vinyl chloride monomer to suspension polymerization reaction in an aqueous medium within a polymerization vessel equipped with a reflux condenser, and subsequently, after the completion of the polymerization reaction, recovering any unreacted monomer, wherein foam generated on the surface of the liquid phase inside the polymerization vessel is eliminated by discharging a high pressure water having a pressure of 20 kg/cm.sup.2 or more substantially linearly to the surface of the liquid phase. The high pressure water discharging is carried out at the polymerization step, particularly from the time when operation of the reflux condenser begins, and/or at the recovery step.

Abstract: In a gas phase olefin polymerization, an olefin is continuously fed to a fluid bed reactor in which a metallocene catalyst is present. At least one compound selected from water, alcohols and ketones is added in a specified amount simultaneously with the feeding of the olefin. Thus, an olefin polymer having a satisfactory drop second count index as defined by the below indicated formula is produced: ##EQU1## wherein t.sub.0 and t respectively represent a flow time measured in the flow test according to ASTM D-1775 of the olefin polymer obtained when none of the water, alcohols and ketones is incorporated in the reactor, and when at least one compound of water, alcohols and ketones is incorporated in the reactor. The flowability of the polymer formed in the reactor is excellent, so that blocking, bridging and the like do not occur during the gas phase polymerization. Thus, it is feasible to stably produce a (co)polymer having excellent particle properties in high yield for a prolonged period of time.

Abstract: The invention relates to continuous gas fluidized bed polymerization of olefins, especially ethylene, propylene, or mixtures of these with other alpha olefins, wherein the monomer-containing recycle gas employed to fluidize the bed is cooled to condense out at least some liquid hydrocarbon. The condensed liquid, which can be a monomer or an inert liquid, is separated from the recycle gas and is fed directly to the bed to produce cooling by latent heat of evaporation. The liquid feeding to the bed can be through gas-induced atomizer nozzles (FIG. 2), or through liquid-only nozzles. The process provides substantially improved productivity of gas fluidized bed polymerization of olefins.

Abstract: A colorable resin particle having an outer shell of a non-sticky polymer and an inner core of a sticky polymer produced in a gas phase fluidized bed reactor at or above the sticking temperature of the sticky polymer using a non-sticky prepolymerized catalyst and processes for producing the colorable resin and the non-sticky prepolymerized catalyst.

Abstract: The present invention relates to a continuous process for the polymerization of olefin(s) utilizing a metallocene catalyst or catalyst system in a continuous slurry or gas phase polymerization process for polymerizing monomer(s). The invention is more particularly drawn to a gas phase polymerization process for polymerizing one or more olefin(s), alone or in combination, in the presence of a metallocene catalyst system in a fluidized bed reactor, preferably operating in a condensed mode.

Abstract: The present invention provides a process and apparatus for feeding powders such as fine, cohesive, or powdery particulate materials from a low pressure system to a high pressure system. There is provided in a preferred embodiment a process and apparatus of pressurizing and feeding carbon black fluff to a polymerization reactor, particularly a gas phase fluidized polymerization reactor to provide for a close-coupling of a carbon black reactor to a polymerization reactor.

Abstract: The polymerization of tetrafluoroethylene in aqueous suspension can be carried out with high conversion if the medium is thoroughly mixed using an axially conveying stirrer element in such a manner that a cone forms at least as far as the vicinity of the stirrer element. In the region of this stirrer element there are expediently arranged baffles which extend only over a part of the filling height of the reactor.

Abstract: In a process for the continuous preparation of polymers from reaction components, in particular of copolymers of styrene and acrylonitrile, by mass or solution polymerization, the reaction components are passed through a circulation reactor which has at least one tube reactor in which is arranged at least one static mixing element through which a liquid heat-transfer medium flows. The static mixing element has multiply curved pipelines.

Abstract: A process for the production of elastomeric polypropylene is disclosed. The process entails contacting the propylene monomer neat or in an unreactive hydrocarbon solvent, with a catalyst in a recirculated, stirred reactor at a temperature of about 60.degree. to 80.degree. C. thereby producing elastomeric polypropylene. The reactor contents are in the slurry/solution phase and are essentially free of catalyst poisons. The reactor is capable of recirculating contents that are very viscous such that the reactor contents are well mixed while a portion of the contents of the reactor containing propylene, any solvent, and elastomeric polypropylene are continually removed by the use of a high viscosity pump to recover the elastomeric polypropylene.

Abstract: Process for the gas-phase polymerization of ethylene and ethylene mixtures with .alpha.-olefins CH.sub.2 .dbd.CHR in the presence of a high activity catalyst comprising a titanium compound containing at least one Ti-halogen bond, supported on magnesium dichloride in active form said process comprising the steps of: (a) contacting the catalyst component; (b) prepolymerizing ethylene or ethylene mixtures with .alpha.-olefins in order to produce a polymer amount of from approximately 5 g per g of solid component, up to an amount corresponding to about 10% of the final catalyst yield; (c) polymerizing ethylene or ethylene mixtures with .alpha.-olefins in the gas-phase, in the presence of the prepolymer-catalyst system obtained in (b), while maintaining in the gas phase a molar concentration concentration of the alkane comprised between 20 and 90% with respect to the total gases.

Abstract: Disclosed is a process for producing a methacrylate polymer, wherein a monomer feed composed of methyl methacrylate or a mixture of at least 70 weight % of methyl methacrylate and not more than 30 weight % of one or more vinyl monomers copolymerizable with methyl methacrylate is continuously bulk polymerized in a substantially perfect mixing state to give a polymer composition having a polymer content of 40-70% by weight in a continuous manner, which comprises carrying out the bulk polymerization in the reactor which is filled up with the polymer composition leaving substantially no gas phase therein and which is maintained in a thermally insulated state allowing substantially no exchange of heat with the external environment at a polymerization temperature of 120.degree.-180.degree. C.

Abstract: A process for the continuous preparation of polymers from reaction components, in particular of copolymers of styrene and acrylonitrile, by bulk or solution polymerization, where the reaction components are passed through the tubes of a recycle reactor, the recycle reactor has at least one tube bundle reactor with straight tubes around which a liquid heat-transfer medium flows, and each tube bundle reactor consists of at least two shell and tube heat exchangers which are connected together by at least one intermediate mixing section. Moreover the volume of the shell and tube heat exchangers is at least 50% of the total volume of the arrangement. The intermediate mixing sections consist of tubes with static mixing elements, around which tubes a heat-transfer medium flows.

Abstract: The present invention provides a suspension polymerization method for producing a polymerized particle having cavities in the particle.

Abstract: Anionically (co)polymerizable vinyl or diene compounds are polymerized in solution and in a reaction zone in the form of a flow tube, using an organometallic initiator, by a continuous process in which the reaction takes place essentially without heat exchange with the environment, the residence time is less than 5 minutes and the reaction zone contains no moving parts.

Abstract: The present invention relates to a gas phase process for the polymerization of olefins utilizing a metallocene catalyst system to produce polymers having a low density and a relatively high molecular weight. More particularly, the gas phase process of the invention is directed forward the production of very low density polymers, for example rubbers, elastomers and plastomers.

Abstract: The present invention relates to a continuous process for the polymerization of olefin(s) utilizing a metallocene catalyst or catalyst system in a continuous slurry or gas phase polymerization process. The invention is more particularly drawn to a gas phase polymerization process for polymerizing one or more olefin(s) in the presence of a metallocene catalyst system in a fluidized bed reactor in the absence of or with a low mount of a scavenger.

Abstract: For gas phase polymerization reactions in the presence of an unsupported polymerization catalyst, there is provided a process for introducing a liquid catalyst so as to provide a resin particle lean zone such that the average particle size of the resin produced ranges from about 0.01 to about 0.06 inches.

Abstract: An immobilized Lewis Acid catalyst system for the carbocationic polymerization of olefin monomer is provided. The catalyst comprises a porous polymer support having catalytically active Lewis Acid residue bonded to the surface of the support including the pore surfaces.

Abstract: The present invention relates to an agitator for suspension polymerization having a more improved structure in effect in contrast to the earlier agitator. The present invention also relates to an improved suspension polymerization method of vinyl chloride using a polymerization reactor equipped with that agitator, by which vinyl chloride resin having excellent quality can be prepared with a diminution of the number of fish eyes which cause many problems such as deterioration of the processed article, low productivity, etc.

Abstract: Agitator blades formed by connecting a plurality of frame members are provided in a cylindrical or conical container to realize the agitator blade structure without rotary shaft. Therefore, less liquids being treated adhere onto the rotary shaft or the agitator blades and less residue of the liquids is formed, making it possible to obtain a final high viscosity polymer using the same agitator vessel preventing the quality from being deteriorated.

Abstract: This invention relates to a process for transitioning between incompatible polymerization catalyst systems. Particularly, the invention relates to a process for transitioning from an olefin polymerization reaction utilizing a traditional Ziegler-Natta catalyst system to a metallocene-olefin polymerization reaction.

Abstract: The method for controlling a polymerization rate, in a continuous radical polymerization of mainly styrene monomer using a complete mixing type reactor, without substantially changing an average molecular weight of a polymer formed, comprising the steps of: (a) keeping a polymerization temperature substantially constant at t(.degree.C.), (b) setting a feeding rate of the styrene monomer to A times larger rate than that in a polymerization conducted in the absence of a radical polymerization initiator, and (c) controlling an amount of the radical polymerization initiator added in the range of from (0.1/n).times.10.sup.-3 to (2.0/n).times.10.sup.-3 mol per 1 liter of the monomer, n being a number of radical generating functional groups present in one molecule of the radical polymerization initiator, such that a polymer concentration x satisfy the mathematical expression: x.gtoreq.0.3t+6.multidot.

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: By utilizing the vapor phase polymerization techniques of the present invention, numerous distinct and highly beneficial advantages are realized. For instance, cis-1,4-polyisoprene rubber and high cis-1,4-polybutadiene rubber having a consistent and controllable molecular weight can be easily and practically prepared without utilizing a solvent. The subject invention more specifically discloses a method for vapor phase polymerizing isoprene into cis-1,4-polyisoprene in a process comprising the steps of:(1) charging into a reaction zone said isoprene and a preformed catalyst system which is made by reacting an organoaluminum compound with titanium tetrachloride, preferably in the presence of at least one ether; wherein the isoprene is maintained in the vapor phase in said reaction zone by a suitable combination of temperature and pressure;(2) allowing said isoprene to polymerize into cis-1,4-polyisoprene at a temperature within the range of about 35.degree. C. to about 70.degree. C.

Abstract: Described herein is a continuous process for polymerizing 1-alkenes. In this process, which operates free of any hydrogen control feed, the resultant polymer has an inherent viscosity that is closely centered around a predetermined targeted value. If desired, the targeted value can be changed while the process is being performed. The process is carried out in a reactor that allows for essentially plug flow of material passing therethrough. Additionally, the temperature profile of the reactor is controllable.

Abstract: The present invention provides a method for the polymerization of free-radically polymerizable vinyl monomers in a batch reactor under essential adiabatic conditions.

Abstract: The present invention relates to a process for continuous gas-phase polymerization of olefin(s) in a fluidized and/or mechanically stirred bed reactor, comprising a stage of drawing off the polymer out of the reactor, wherein a portion of the bed is transferred into a lock hopper and is then isolated from the reactor in the lock hopper for a period of 5 to 120 seconds so that a substantial amount of the olefin(s) in the said portion polymerizes, before the polymer thus isolated in the said portion is discharged out of the lock hopper. The process advantageously reduces the amount of the gas drawn off with the polymer to be recycled into the reactor and improves the degassing of the polymer by the heat of the polymerization reaction during the isolation period in the lock hopper (FIG. 1).

Abstract: The invention relates to a fluidized-bed reactor for polymerization of olefins, said reactor comprising an upper section of the reactor acting as a polymerization space in which olefin monomers are polymerized in a fluidized bed formed by polymerizing particles and a lower section of the reactor acting as a mixing space through which circulating gas removed from the top of the polymerization space is passed to the fluidized bed contained in the lower part of the polymerization space through a horizontal gas distributor plate in order to maintain the fluidized state of the bed, in which arrangement the circulating gas is passed to the lower section of the reactor via one or more inlet nozzles and the bottom section of the reactor is additionally provided with means for directing the circulating gas.

Abstract: A process for controlling the particle growth of a polymer in a gas phase polymerization reaction by using an inert particulate material and an unsupported liquid polymerization catalyst.

Abstract: A fluidized bed polymerization process in which a central mixing element sweeps the interior of the bed. The mixing element contains agitator arm which pass adjacent to the reactor walls and a have a perforated surface. Gas is directed to the central mixing shaft and distributed to the agitator arms.

Abstract: A polymerization method used, particularly, in suspension polymerization of vinyl chloride, comprising a polymerization vessel (1) having a substantially cylindrical inner space, said inner space of said polymerization vessel being provided with a plurality of baffles (5) comprising vertically extending pipes, and a vertically continuously extending coil (6), and a refrigerant being passed through said baffles and said coil. High-cooling performance can be obtained, a high-speed reaction in a large-sized polymerization vessel becomes possible, and a stable polymerization reaction can be carried out. A high-quality and uniform polymer that has few fish eyes and has a high bulk specific gravity can be obtained.

Abstract: The present invention provides a suspension polymerization method for producing a polymerized particle having cavities in the particle.