Abstract: Compositions for removing contaminants from plastics processing equipment are described herein. The compositions may include a polymeric carrier component, an oxidizing agent, an abrasive and/or a gas agent. Methods of preparing the compositions described herein and methods of removing contaminants from plastics processing equipment are also described.

Abstract: This disclosure relates to systems and processes for cooling polymer product mixtures manufactured at high pressure. The processes of the invention involve cooling and then subsequently reducing the pressure of the product mixture from the reactor. In the systems of the invention, a product cooler is located downstream of the high pressure reactor and upstream of a high pressure let down valve.

Abstract: A process for continuously preparing water-absorbing polymer beads, comprising the drying of a polymer gel on a forced-air belt dryer, the water content of the polymer gel being used to control the forced-air belt dryer during or after the drying.

Abstract: A process for recovering waste latex material from a manufacturing plant, treating the recovered waste latex material, and subsequently utilizing the recovered and treated waste latex material in a manufacturing plant. Waste latex material is recovered and treated to provide a fine, sand-like material that is suitable for reintroduction into a latex adhesive manufacturing process.

Abstract: Method of reducing fouling in an elastomer polymerization process that includes providing a reactor capable of housing an industrial-scale elastomer polymerization reaction, and applying a mechanical force to the reactor so as to create a vibration in at least one wall of the reactor, in which fouling is reduced in the reactor. In one embodiment the reaction is an industrial scale butyl polymerization reaction and the reactor is a butyl polymerization reactor.

Abstract: A process for recovering waste latex material from a manufacturing plant, treating the recovered waste latex material, and subsequently utilizing the recovered and treated waste latex material in a manufacturing plant. Waste latex material is recovered and treated to provide a fine, sand-like material that is suitable for reintroduction into a latex adhesive manufacturing process.

Abstract: The invention relates to a method for mixing a polyester with caustic material including providing a polyester, preferably PET, mixing the polyester with the caustic material; and heating the mixture in temperature stages defined as a function of a reaction sequence of the reaction between the PET and the caustic material.

Abstract: The invention relates to a process for removing fouling on a surface, wherein the surface is contacted with an aqueous solution of a guanidine of formula R1R2N—C(?NH)—NR3R4??(I) wherein R1, R2, R3 and R4 may be the same or different and each of R1, R2, R3 and R4 is hydrogen or hydrocarbyl.

Abstract: A continuous process wherein polymers or polymeric materials can be subjected to multiple sequential processing systems of differing temperatures and process conditions to synergistically enhance the pelletization and crystallization of those polymers and polymeric formulations, dispersions, and solutions. The multiple sequential processing systems include the processes and equipment for mixing/extrusion, pelletization, multiple transportation processes, crystallization, multiple drying processes, and optional post-processing manipulations of pellets formed. Multiple serial and/or parallel crystallization processing systems are disclosed.

Abstract: The present case relates to a process for the purification of lactide from a crude lactide vapor product stream which process comprises a rectification/condensation step leading to a lactide-enriched condensate.

Abstract: This invention relates to a process comprising contacting an polymerization reactor effluent with a fluorinated hydrocarbon and thereafter recovering olefin polymer, where the fluorinated hydrocarbon is present at 5 volume % to 99 volume % based upon the volume of the effluent and the fluorinated hydrocarbon, and where the polymerization is a continuous polymerization of at least 75 mole % of hydrocarbon monomers, based upon the total moles of monomer present in the reactor.

Abstract: This invention relates to a process for maintaining heat transfer capacity of a cycle cooler while polymerizing olefin(s) in the presence of catalyst and a carboxylate metal salt by controlling the amount of carboxylate metal salt present in the reaction system. In particular, the invention relates to maintaining a cycle cooler performance parameter substantially constant while polymerizing olefin(s) in the presence of a carboxylate metal salt and a conventional-type transition metal polymerization catalyst compound, or a metallocene-type polymerization catalyst compound. This invention further relates to a process wherein the cycle cooler performance parameter is a heat transfer capacity of the cycle cooler, a pressure drop across the cooler, or a cooler approach temperature of a cycle cooler.

Abstract: A process for the solution polymerization of olefins with improved on-stream time is provided. The solution polymerization process of the current invention comprises a method for the on-line removal of foulant material from one or more heat exchangers downstream of a polymerization reactor. Removal of foulant material is accomplished by deliberately applying a positive pressure differential across a heat exchanger. In the process of the current invention, reactor shut down is not required for the purpose of cleaning foulant material from a heat exchanger.

Abstract: The present invention relates to the use of an additive for improving the flowability of fines and their reintroduction into a process for the continuous gas-phase (co-) polymerisation of olefins in a fluidized bed or sub-fluidized bed reactor.

Abstract: A process for deactivating an active catalyst species in an olefin polymer stream exiting a polymerization reactor and neutralizing catalyst residues, as well as reducing corrosion, plugging or fouling of olefin production and recovery equipment and imparting antioxidative properties to an olefin polymer comprising adding a catalyst deactivator and an alkaline earth metal salt of a phosphoric- or phosphonic acid to an olefin polymer stream exiting a polymerization reactor, each in a quantity at least sufficient to deactivate active catalytic species in the polymer stream and neutralize catalyst residues, respectively, and subsequently recovering the resulting polymer product.

Abstract: This invention relates to a process comprising contacting an polymerization reactor effluent with a fluorinated hydrocarbon and thereafter recovering olefin polymer, where the fluorinated hydrocarbon is present at 5 volume % to 99 volume % based upon the volume of the effluent and the fluorinated hydrocarbon, and where the polymerization is a continuous polymerization of at least 75 mole % of hydrocarbon monomers, based upon the total moles of monomer present in the reactor.

Abstract: Disclosed is a method for reducing fouling in an apparatus and process for separating polyolefin from a slurry in a slurry polymerization reactor system comprising contacting in a reactor at a pressure of at least 2000 kPa a catalyst composition and ?-olefin monomers to form a polyolefin reaction mixture; transferring the polyolefin reaction mixture to a high pressure separator, wherein the pressure in the high pressure separator is within the range of from 200 to 2500 kPa; and contacting the polyolefin reaction mixture with an organic amine prior to its entering the high pressure separator.

Abstract: A specific nonionic surfactant is added to a component mainly comprising hydrocarbons before passing through a heat exchanger in a petrochemical plant or a polyolefin production plant, whereby fouling of the heat exchanger can be efficiently prevented, that is, the performance of the heat exchanger can be prevented from being deteriorated, and long-term operation is feasible without sacrificing the speed of production. The nonionic surfactant is preferably a polyoxyalkylene compound represented by the general formula [I] below, more preferably a compound represented by the general formula [II] below. R1—O—[CH2—CH(R3)—O]k—R2[I] wherein R1, R2 and R3 are selected from a hydrogen atom, a C1 to C20 alkyl group, a C6 to C20 aryl group and a C1 to C20 acyl group, and may be the same or different from each other. HO—(CH2CH2O)m—[CH2CH(CH3)O]n—(CH2CH2O)pH[II] wherein m, n and p each represent the average number of repeating units, and m is in the range of 1 to 20, n is 2 to 50 and p is 1 to 20.

Abstract: This invention provides a method for producing a polymer alloy, a polymer alloy as well as a molded article, a transparent molded article and an optical film, which is obtainable by using the polymer alloy. The invention is a method for producing a polymer alloy, which comprises at least: a step 1 of mixing two or more resins incompatible with each other at ambient temperature and pressure with a solvent being in a liquid or gas state at ambient temperature and pressure; a step 2 of heating and applying pressure to said solvent into a high-temperature and high-pressure fluid or a supercritical fluid and mixing the solvent in this state; and, a step 3 of cooling the mixture obtained in said step 2 rapidly to the glass transition temperature or less without releasing the pressure of the mixture.

Abstract: The invention relates to a washing process for cleaning polymers containing N or amine, ammonium or spirobicyclic ammonium groups, comprising cationic groups containing N, in addition to suitable counterions, whereby the gelled-out polymers are obtained through polymerization and cross-linking by a) adding a base which is partially or fully deprotonated, b) the partially or fully deprotonated polymers are washed, then c) optionally, are reprotonated in an organic solvent or in an organic solvent/water mixture by adding an acid, whereupon d) optionally, they are washed in an organic solvent or an organic solvent/water mixture in order to shrink the gels and optionally, e) in connection with step c) or d), the steps a)-c) or -d) are repeated.

Abstract: A toner extruder method for the preparation of a toner resin extrudate from a resin is provided. The method includes conveying a base resin to an aperture in a housing of a toner extruder, the housing surrounding a conveyor, providing a lead-in gap at a feed port end of the conveyor, inhibiting adhesion of melted resin to walls of the aperture, adding chemical initiator to a toner extruder, mixing the base resin and the chemical initiator within the extruder to form the mixed resin, and conveying the mixed resin within the extruder to an extruding die. Inhibiting adhesion can include repelling melted base resin into a flow of base resin, inhibiting heat transfer from the extruder to the base resin at the aperture by, for example, spacing at least one of the housing and the conveyor from the resin at the aperture.

Abstract: The present invention provides: a water-absorbing composition such that portions containing the water-absorbing composition in a high concentration exhibit excessive-liquid permeation buffering effects in absorbent articles comprising the water-absorbing composition and hydrophilic fibers; and a use of this water-absorbing composition. The water-absorbing composition comprises a water-absorbent resin and an excessive-liquid permeation buffer, wherein the water-absorbent resin is a product by a process including the step of further crosslinking the surface vicinity of a crosslinked polymer, and this water-absorbing composition is characterized by having a liquid permeation buffering index of not less than 0.

Abstract: This invention is an improvement upon the known process for polymerization of polytrimethylene terephthalate by esterification of terephthalic acid or dimethyl terephthalate with 1,3-propane diol, precondensation of the esterification product to produce a precondensation product, and polycondensation of the precondensation product to produce polytrimethylene terephthalate and, optionally, solid stating of this product to produce higher intrinsic viscosity polytrimethylene terephthalate. The cyclic dimer of terephthalic acid and 1,3-propane diol is produced as a byproduct of the above process and the improvement comprises (a) recovering the cyclic dimer from the polymerization, (b) reacting from 0.5 to 25 percent by weight of the cyclic dimer in 1,3-propane diol in the presence of from 0.1 to 10 percent by weight of the cyclic dimer of a basic catalyst for five minutes to 24 hours at 50 to 210° C.

Abstract: A continuous process for preparing polyester prepolymer comprising the steps of esterifying a diacid with a diol, reacting the esterified product with additional diol, and passing the product downward through a countercurrent column reactor while inert gas flows upward through the column reactor. The resulting prepolymer product has fewer acid end groups than the esterified material.

Abstract: The present invention provides a melt process for the manufacture of thermoplastic solvent-free polycarbonates with the use of a continuously operated tubular reactor for monophenol vaporization.

Abstract: Amino resins that contain more free formaldehyde than is desirable for health and/or pollution reasons can be treated with a mixture of diketo reagents (or their nitrogen analogs) and other compounds containing amino moieties to reduce the free formaldehyde content while not diminishing, and in some cases even enhancing, the ability of the resins to function according to their normal uses. The invention is especially useful for melamine-formaldehyde resin dispersions useful to detackify paint.

Abstract: An integrated process for the manufacture of lactide from a solution of lactic acid in de-ionized water comprising the sequential steps:A. Dehydrating the aqueous lactic acid in at least two stages to effect condensation polymerization of the lactic acid and the formation of oligomers in which the average number of monomer units is 8-25, the dehydration stages being conducted in equipment fabricated from low ferrous materials;B. Thermally cracking the oligomers in the presence of depolymerization catalyst to form lactide vapor of which the average residence time within the cracking zone is less than 15 seconds;C. Condensing the lactide vapor and fractionally distilling the condensate to remove concentrated lactide as a liquid sidestream; andD. Subjecting the concentrated lactide sidestream to melt crystallization to separate purified lactide having an Acidity Potential less than 6.

Abstract: A process for preparing a silicon carbide foam by impregnating a polyurethane foam with a suspension of silicon powder in an organic resin, heating progressively to polymerize the resin, heating further to carbonize the polyurethane foam and resin, and finally further heating to carburize the silicon contained in the resin suspension by means of carbon obtained from the carbonization of the foam and resin. The foam obtained is characterized by high macroporosity and a mesoporosity which is variable according to the carburizing temperature.

Abstract: Inhibition of popcorn polymer growth by treatment with heat. Heat can be applied to extant popcorn polymer, particularly in the absence of organic material from which the popcorn polymer is formed. A chemical inhibitor of popcorn polymerization can be used in conjunction with the heat treatment.

Abstract: A process for the production of polycarbonates is disclosed. Accordingly, oligocarbonate in the melt is passed through a heated tube and inert gas is simultaneously introduced by injecting to the melt.

Abstract: A polymer scale preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising an alkaline solution containing a condensation product of (A) an aliphatic diamine compound and (B) an aromatic tetracarboxylic acid anhydride. This agent is used for forming a coating on the inner wall, etc. of a polymerization vessel. Such a vessel is effective in preventing polymer scale deposition, not only on the areas in the liquid phase but also near the interface between the liquid phase and the gas phase in the vessel, and useful in producing a polymer that shows very few fish eyes and good whiteness when formed into sheets or the like.

Abstract: Waxes and polymeric waxes can graft with a coupling agent by employing a radical process. The resulted grafted waxes can be applied:1. For Coating and bonding with surfaces of materials to be applied as water-proofing antirust and reinforcing fillers.2. As enhancing coupling agent to bond with plastics, rubber and asphalt.3. As adhesive materials.

Abstract: A method for metered supply of a delivered material to the next step, which method is characterized by regulating the thickness of the material on a conveyor before the material in the process of transfer on the conveyor from the incoming end thereof to the outgoing end thereof reaches the outgoing end, removing portions of a prescribed amount one at a time from the upper side part of the material by means of a scraping member adapted to cut into the upper side part of the material causing the removed portions of the upper side part of the material to be discharged past the outgoing end of the conveyor by means of the scraping member and, at the same time, causing the lower side part of the material discharged into by the scraping member to be discharged past the outgoing end by means of the conveyor, and an apparatus therefor.

Abstract: The invention includes a process for facilitating the handling of tacky polymers (specifically amorphous polypropylene and amorphous ethylene propylene copolymers) during their polymerization comprising:a. preparing a mixture of a tacky polymeric material and a carrying phase for said polymeric material at a temperature and pressure sufficient to maintain said carrying phase as a liquid;b. flashing said mixture to a flash pressure low enough to effect vaporization of said carrying phase, as well as autorefrigeration of said polymeric material to its non-tacky, easy-handling temperature range; andc. separating the thus autorefrigerated polymeric product from its carrying phase wherein said carrying phase will dissolve sufficient polymer to form a liquid mixture.The invention also includes an apparatus for carrying out this process.

Abstract: The invention disclosed herein is a single-pass, horizontal heat exchanger, of the shell and tube type, which is designed for preheating of a viscous material, such as the reactor effluent of a polyethylene solution. The heat exchanger is made in three sections, each of which can be heated independently with a heating fluid, so that a temperature profile can be easily maintained along the entire length of the exchanger. Also, each section can be removed from the exchanger unit independently of the other sections, for cleaning, if the section becomes plugged.

Abstract: The present invention relates to a process and apparatus for the gas-phase polymerization of olefins in a fluidized-bed reactor maintained at a temperature T1. A gaseous reaction mixture comprising the olefins to be polymerized passes through the reactor and is recycled to the reactor by means of a recycling line comprising successively a first heat transfer means, a compressor and a second heat transfer means. The present invention consists in introducing a readily volatile liquid hydrocarbon into the inlet of the first heat transfer means or into the recycling line, upstream and in the vicinity of the first heat transfer means. The first heat transfer means cools the gaseous reaction mixture to a temperature T2, below T1, while volatilizing the readily volatile hydrocarbon and without condensing a constituent of the gaseous reaction mixture. The second heat transfer means cools the gaseous reaction mixture to a temperature T3, below T2, for maintaining the fluidized-bed at the desired temperature T1.

Abstract: A process for the continuous production of linear thermoplastic polyesters comprises the following steps:(a) passing a transesterification or esterification product of an aliphatic or aromatic dicarboxylic acid having a molecular weight of <300 or an ester-forming derivative thereof with an aliphatic or cycloaliphatic diol having a molecular weight of <250 which may additionally contain a poly(alkylene oxide) glycol having a molecular weight of 400 to 4000 at from 250.degree. to 360.degree. C. under a pressure of 0.5 to 20 mmHg downward in the course of a residence time of from 3 to 10 minutes through an essentially upright tubular precondensation zone equipped with internal fitments having a free surface area of from 0.3 to 1.5 m.sup.2 /l to form a precondensate and a vaporous diol having a molecular weight <250,(b) separating into a precondensate and vaporous diol and(c) further condensing the precondensate in the bottom phase at from 240.degree. to 290.degree. C. under a pressure of from 0.

Abstract: A chemical cleaning method for removing scales and other substances deposited on the interior of a polymerization reactor used in emulsion polymerization or suspension polymerization. This method comprises chemically cleaning the interior using an aqueous solution or dispersion of an alkali agent and a surfactant. According to this method of cleaning, scales deposited on the interior of a polymerization reactor, in particular, scales deposited during polymerization on the inside surface, an agitator and baffle-plates of the reactor are completely removed.

Abstract: In the process of producing hydroxylated polybutadiene from a diene monomer in the presence of hydrogen peroxide and a solvent, wherein the solvent is recovered by distillation for reuse; after separation of the hydroxylated polybutadiene from mixture containing such solvent and reaction impurities, the improvement comprising subjecting said mixture to the action of an alkali metal hydroxide or a hydrazine prior to distillation.

Abstract: Compositions comprising thermoplastic polymers having added thereto small amounts of a hydroxymethyl-substituted carboxylic acid are usefully employed to remove accumulated polymeric residues from polymer processing equipment.

Abstract: Compositions of salts of water-soluble, carboxyl-containing polymers and surface active agents, deposited on polymerization reactor surfaces exposed to polymerization mixtures, substantially reduce or eliminate undesirable polymer build-up on reactor surfaces during aqueous polymerization of vinylidene monomers, even when the amount of carboxyl-containing polymers deposited on the reactor surfaces is very small.

Abstract: A method for removing polymer scales adhering to the inner surface of a polymerization vessel, which comprises polymerizing vinyl chloride monomer in an aqueous medium, discharging the resulting vinyl chloride polymer together with the aqueous medium from the polymerization vessel, thereafter placing in the vessel both a reaction product resulting from the reaction of an amine and acrylic acid or its derivative and an organic liquid which can dissolve or swell the polyvinyl polymer, and washing the inner surface of the vessel with the organic liquid solution of the reaction product.

Abstract: Method of adding water and a hydroxide of an alkali metal or alkaline earth metal to a washing solvent such as an alkylamide and/or alkylsulfoxide when washing and removing high molecular substances stuck on the interior of a production apparatus or molding machine for an aromatic vinyl-acrylonitrile copolymer. A method for regenerating and recovering the washing solvent used for the above-mentioned washing and removal by means of an evaporator and distillation tower.

Abstract: A machine for solid phase polymerization comprises: a system for supplying particles of a synthetic polymer; a reaction system for effecting solid phase polymerization of the particles, fed from the supplying system, under a vacuum and heated condition; and a system for discharging the solid phase polymerized particles. The supplying system includes a pre-treatment apparatus comprising: a pre-crystallizer of a vertical agitator type; and a beater of a horizontal type. The reaction system includes a horizontal reaction vessel having a horizontal rotary shaft with a helically formed screw vane. The screw vane has a multiplicity of small through-apertures, and scrapers extend axially extending between adjacent screw vane portions. Intermediate pots having specially designed vacuum breakers are disposed at locations between the reaction system and the supplying system and between the reaction system and the discharging system.

Abstract: This invention relates to a polymerization reaction vessel having a coating on the inner surfaces thereof resulting from applying thereto a coating composition containing, as a primary ingredient, the reaction product or oligomers of (1) an alkyl or halogen substituted phenol, such as p-chlorophenol and the like, (2) a condensing agent, such as formaldehyde, and the like, and (3) a polyhydric phenol, such as resorcinol, and the like, dissolved in water or an aqueous alkaline solution. When polymerizing olefinic monomers, such as vinyl halides, vinylidene halides, and vinylidene monomers, having at least one terminal ##STR1## and mixtures thereof, polymer buildup on the inner surfaces of the reaction vessel is substantially eliminated. Further, multiple charges or batches of polymer can be made in said internally coated reaction vessel without opening the same between charges thus preventing the escape of unreacted monomer(s) to the surrounding atmosphere.

Abstract: The process of the preparation of production quantities of lens devices fabricated from synthetic resinous substances, normally referred to as "plastic lenses." The process utilizes a molding formulation which enables reusable mold cavities to be utilized, the formulation providing a proper balance between a number of processing parameters or variables, one of the primary parameters being the maintenance of a proper adherence or release capability between the surface of the lens being fabricated and the surface of the mold cavity. Specifically, it has been found that certain silanes when incorporated in the molding formulation controls the parameters so as to provide for controllable release of the lens product from the mold.

Abstract: A process for preventing deposits when venting steam containing entrained polymer from high pressure reactors used for preparing nylon from dicarboxylic acid and diamine. The hot steam generated during condensation polymerization of the reactants is vented through a pressure-control valve at a rate which maintains a desired pressure in the reactor. Deposit of polymer in the valve or vent pipe after release of pressure is prevented by injecting water into the low pressure side of the valve or into the subsequent vent pipe. At least sufficient water is used to saturate the vented steam and to wet the walls of the vent pipe.

Abstract: Polyphenylene ethers produced by an oxidative coupling of a phenol in the presence of an oxygen-containing gas and a metal-amine complex catalyst are freed of catalyst and stabilized against molecular weight loss. Removal of the metal component and molecular weight loss control are effected by contacting the solution with a compound capable of selectively complexing with the metal in combination with a dihydric phenol and a mild reducing agent. The process is less expensive than prior art procedures because less dihydric phenol is needed, and the metallic residue content of the polyphenylene ether is reduced to very low levels.

Abstract: Vinyl chloride monomers or a monomeric mixture composed mainly of vinyl chloride is bulk-polymerized in a polymerization vessel. The inner walls and other surfaces of said vessel, coming into contact with the monomer or monomers, are coated with one or more specifically selected inorganic or organic compounds having a solubility greater than 0.5 g in 100 g of water at 25.degree. C and a boiling point higher than 60.degree. C. This bulk polymerization method serves to greatly reduce the deposition of polymer scale on the vessel walls and other surfaces. In addition the polymer scale deposited can be readily separated and removed by merely washing with water or gas under pressure. The present method provides high quality polymers.

Abstract: In the aqueous polymerization of vinyl chloride and vinylidene chloride polymers and copolymers, the polymer build up normally experienced in many areas of commercial polymerization reactors is reduced, or when such polymer build up does occur it is more readily removed, when these trouble areas in polymerization reactors are coated with a latex-modified portland cement composition, the polymer in said latex containing carboxyl groups and the polymer having a Tg .degree. C. of less than about 40.degree. C., preferably less than about 25.degree. C.