Abstract: Dicarboxylic acids or esters thereof are recovered from solid phase polyester materials, such as post-consumer products and factory scrap, by subjecting the polyester to at least two hydrolysis stages in at least the first of which the amount of water used is substantially less than needed to effect total conversion of the polyester to the dicarboxylic acid. Also the diol content is controlled in the course of carrying out the hydrolysis. The hydrolysis reactions may be preceded by reaction of the polyester with a diol, the resulting depolymerisation products then being hydrolysed.

Abstract: A method for product recovery method of polyolefins, particularly high-molecular-weight amorphous poly alpha-olefins, wherein the use of water during the method is significantly decreased and wherein the intermediate stage of storing and drying the chunk form of the polyolefin is eliminated. Polyolefins produced in a reactor are heated in a kneader to remove any unreacted monomer(s). The polyolefin material in a liquid form is then transferred directly to an extruder to further remove any unreacted monomer(s) and catalyst(s). Finally, the polyolefin material is pelletized using a pelletizer.

Abstract: A method for removing residual vinyl chloride monomers from an aqueous slurry is disclosed. The method preferably utilizes a tower having a plurality of vertically spaced plates, which define a plurality of chambers, each chamber defined between adjacent plates. The tower features a plate in one of the chambers having a diameter of 1.05 to 5 times larger than the diameter of the plates in chambers above and below the chamber having the large plate. The method is based upon introducing the slurry to a particular location in the tower depending upon the porosity of the polyvinyl chloride in the slurry.

Abstract: Polyester particles in suspension in a liquid can be agglomerated below their melting points and the agglomerated particles are more easily filtered.

Abstract: The invention relates to a process for drying polymeric powders and polymeric agglomerates, in particular thermoplastic aromatic polycarbonate or other thermoplastic polymers such as, for example, acrylonitrile-butadiene-styrene copolymer, in the melt, whereby thermoplastic polymeric powders or polymeric agglomerates containing water or solvent or both are freed from adhering moisture and contained solvent, accompanied by melting, in an apparatus provided with rotating baffles for cleaning the walls of the apparatus and for distribution and transport of the material being dried, by heat input through the walls or through the rotating baffles or both as well as by heat input as a result of shearing action. The process of drying and that of melting for the subsequent granulation are thereby combined.

Abstract: Volatile components are eliminated from polyacrylate melts by distilling off the volatile components by a process in which the volatile components are distilled off under reduced pressure, entraining agents are added to the melts at above 100.degree. C. and the melts are simultaneously circulated.

Abstract: A method for dispersing solid forms of additives in polymers involves adding dispersions or solutions of additive(s) to a solution of polymer in a tubular mixer (preferably in the presence of a stationary mixer). The mixer leads to a steam precipitation step wherein all fluid ingredients in the mixture are volatilized leaving the solid additive and resin in the desired ratio. This results in a uniform dispersion of the additives in the polymer matrix. As a result of the high dispersion, physical properties of a thermoplastic resin, to which the polymer matrix has been added are preserved. In one illustration, PTFE as a drip inhibitor additive, is added to polycarbonate to obtain a highly dispersed PTFE concentrate of improved drip-inhibition without loss of mechanical properties when added to a thermoplastic molding resin.

Abstract: A method of improving the oxidative thermal stability of ethylene polymers is disclosed. The method comprises removing residual unreacted monomer(s), solvent and thermally unstable species from the molten polymer. The resulting polymer is characterized by having an oxidative exotherm of not more than about 50 percent of the original polymer, as measured by differential scanning calorimetry.

Abstract: Polymerization process to obtain elastomeric copolymers or terpolymers based on ethylene for cold flow improver (CFI) having a viscosimetric average molecular weight ranging between 600 and 16,000.a) The process includes polymerizing monomers in suspension in the presence of an alpha-olefin liquid under reaction conditions, in the presence of an amount of solvent from about 5 to 30% by volume of the reactor volume in the presence of a polymerization catalyst able to give the X.sub.2 and/or X.sub.4 parameters, lower less than or equal to 0.02, X.sub.2 and X.sub.4 representing the fraction of uninterrupted methylenic sequences of 2 and 4 methylenic groups between two successive methyl or methylene groups respectively in the polymeric chain, as compared with the uninterrupted total sequences of methylene groups determined by .sup.

Abstract: The invention relates to a method for purifying liquid polysiloxane containing impurities as a low-molecular-weight fraction, by evaporating the low-molecular-weight fraction, in which method a liquid stream of impure liquid material in the form of a bundle of a multiplicity of streams or jets is brought into contact with a flowing gas phase, after which the gas stream, which contains the impurities, is removed and purified liquid material is collected; a device for performing this method and also the use of purified liquid material.

Abstract: Saturated or superheated steam, or an inert gas, or a combination thereof is introduced into a gas phase above a molten acrylonitrile polymer in a vessel having a stirrer, while the polymer has a temperature of at least 120.degree. C. and a pressure at least equal to its autogenous pressure. Any unreacted acrylonitrile monomer, or both any such monomer and any acrylonitrile monomer or water used as a plasticizer are removed by evaporation from the vessel.

Abstract: A process for coagulation finishing (co)polymer by using polyvinyl alcohol as dispersant during said coagulation. In particular, low viscosity block copolymers, comprising at least one block of predominantly conjugated diene and at least one block of predominantly monovinyl aromatic monomer, can be successfully finished. The polyvinylalcohol is characterized by a weight average molecular weight of from 200 to 200,000 and by an average degree of hydrolysis of from 25 to 98%.

Abstract: In a method for the depolymerization and reprocessing of material which consists of polyamide 6 waste and/or oligomer-containing polyamide 6 waste and/or oligomer-containing lactam residues and/or oligomer-containing lactam by hydrolysis in a pressure reactor with the addition of water, the material is melted and the melt is conducted continuously at predetermined temperature through the pressure reactor the inside pressure of which is controlled by the dosaged feeding of water or steam.

Abstract: The invention relates to a process for the treatment of contaminated ethylene glycol resulting during a polycondensation process for the production of polyester. In the course of this polycondensation process contaminated ethylene glycol is continuously predistilled, subjected as a distillation residue to secondary distillation, condensed and then returned to the polycondensation process as decontaminated ethylene glycol, so that an in-line recovery is achieved, which makes superfluous an external distillation installation for the treatment of contaminated ethylene glycol.

Abstract: Microporous crumbs of a hydrogenated block copolymer, produced by the process comprising feeding a solution of a hydrogenated block copolymer in a hydrocarbon solvent at a concentration of said hydrogenated block copolymer within a range from 5% to 60% by weight into hot water while maintaining the temperature of said solution at 40.degree. C.-150.degree. C., and then steam stripping at a temperature higher than the boiling point of the hydrocarbon solvent or higher than the azeotropic point of the hydrocarbon solvent and water when they form an azeotropic mixture and lower than 150.degree. C.

Abstract: A method for dispersing solid forms of additives in polymers involves adding dispersions or solutions of additive(s) to a solution of polymer in a tubular mixer (preferably in the presence of a stationary mixer). The mixer leads to a steam precipitation step wherein all fluid ingredients in the mixture are volatilized leaving the solid additive and resin in the desired ratio. This results in a uniform dispersion of the additives in the polymer matrix. As a result of the high dispersion, physical properties of a thermoplastic resin, to which the polymer matrix has been added are preserved. In one illustration, PTFE as a drip inhibitor additive, is added to polycarbonate to obtain a highly dispersed PTFE concentrate of improved drip-inhibition without loss of mechanical properties when added to a thermoplastic molding resin.

Abstract: A process for achieving a significant reduction in the volatile organic compound content (VOC) of an aqueous polymerization system includes the steps of contacting the aqueous polymerization system with an organic solvent and allowing said organic solvent to be absorbed into polymer particles of said aqueous polymerization system, contacting said aqueous polymerization system and organic solvent with a gas or vapor at temperature and pressure conditions which cause mass transfer of the volatile organic compounds from said latex into said gas or vapor phase, and separating said gas or vapor from said aqueous polymerization system. The solvent is generally absorbed into the polymer particles of the latex and serves as a stripping aid, especially with respect to higher molecular weight compounds which tend to remain trapped in the polymer particles during conventional stripping processes.

Abstract: A method for reducing residual unsaturated monomer content of an aqueous dispersion of a saturated polymer. The method involves contacting the aqueous dispersion with ozone resulting in ozonolysis of unsaturated monomers. The method is simple, economical and can be used with existing production facilities.

Abstract: A low cost method for preparing foamed or aerated asphalt-rubber paving compositions is provided wherein a flowable mixture including respective quantities of asphalt and finally divided reclaimed rubber particles is first directed into a rocket-type reactor along with steam and/or water, thereby subjecting the mixture to conditions of elevated temperature, pressure and shear. Thereafter, the initially reacted mixture is passed into a pressurized, secondary reaction vessel system in order to complete the gelation reaction in a period of, e.g., 7-15 minutes. The preferred apparatus (10) includes a rocket-type primary reactor (12) presenting a confined reaction zone (20); asphalt-rubber and water/steam conduits (42, 48) communicate with the zone (20). The output (24) of the primary reactor (12) feeds directly into a pressurized tank (66) forming a part of the downstream secondary reaction and recovery system (14), where the gelation reaction is completed.

Abstract: A process for the production of a polycarbonate powder comprising introducing an organic solvent solution of polycarbonate and steam into a mixing nozzle and obtaining the polycarbonate powder from a mixture ejected from the mixing nozzle, wherein the organic solvent solution contains 3 to 45% by weight of the polycarbonate, and the ratio of the weight of steam/the weight of an organic solvent in the organic solvent solution is 1/10 to 1/5.

Abstract: A method for producing a vinyl chloride resin, which comprises spray drying a vinyl chloride polymer latex by means of a double fluid nozzle, wherein steam or a gas mixture of steam and an inert gas is used as spray gas.

Abstract: Aqueous emulsions, at least 80% of which have been polymerized, are treated by a process which comprises the separate steps of: a) initially treating the emulsion with a sufficient amount of a free radical generator in an amount and for a time sufficient to reduce the residual monomer content to from about 1500 to about 6000 part per million, and b) subsequently subjecting the emulsion to steam stripping under vacuum, without significantly degrading or destabilizing the emulsion, to thereby reduce the residual monomer content to from about 5 to about 500 parts per million.

Abstract: A process for removing volatile constituents from a polymer dispersion or solution by stripping with a carrier gas is disclosed. The carrier gas being, in the case of a polymer solution, the vapor of the solvent used for the polymer solution as an inert gas saturated with said vapor. In the case of a polymer dispersion, the vapor of the dispersing medium used for the polymer dispersion or an inert gas saturated with said vapor. In both processes certain amount of the carrier gas is passed through the polymer dispersion or solution, the volatile constituents taken up the carrier gas on passage through the polymer dispersion or solution are then removed from the carrier gas in such a manner that the energy content of the carrier gas remains essentially unchanged. The carrier gas thus obtained is then reused for further removal of volatile constituents from the same polymer dispersion or solution by stripping.

Abstract: An improved process is provided for the recovery of a polymer from a solution thereof in a process wherein the polymer solution is contacted with hot water and steam to yield a slurry in water of polymer particles and a vapor stream comprising water vapor and the solvent, the slurry in water of polymer particles is passed to means to grossly separate the polymer particles and the water and the polymer particles are dried, wherein the water contains small particles of polymer and a portion thereof is mixed with the original polymer solution and the remaining portion is passed to the vessel wherein the polymer solution is first contacted with hot water and steam.

Abstract: A process for the continuous processing of vinyl polymer latices to produce thermoplastically processible vinyl polymer powder by coagulating a stream of a vinyl polymer latex by the addition of a stream of a coagulant with intensive mixing and shearing in a cascade of vessels at an average residence time per vessel of 10 to 60 minutes and at temperatures from 50 to 120.degree. C., volatile auxiliary substances and residual monomers in the polymer being optionally removed by steam distillation and part of the serum separated from the vinyl polymer being added to the stream of coagulant.

Abstract: A process for cleaning thermoplasts is described. The thermoplast to be cleaned is introduced between the discs of a plast compactor and substantially freed from unwanted residues from the polymerization process by the force and rise in temperature produced by the movement of rotation.

Abstract: This invention concerns a method for precipitating polymers from a liquid using at least one precipitant fluid, including a feed line, a nozzle plate having at least one outlet orifice for a polymer containing fluid with the outlet orifice communicating with the feed line, at least one nozzle for at least one precipitant fluid, the axis of which is arranged approximately perpendicularly to the axis of the outlet orifice, a precipitation chamber positioned on the side of the nozzle plate wherein at least one nozzle for at least one precipitant fluid is located, a discharge line for discharging a mixture which contains the precipitated polymer and a degassing chamber which is connected to the discharge line.

Abstract: A conductive substrate and electrostatic recording media which incorporates such a conductive substrate are disclosed. The disclosed conductive substrate and recording media are applicable to electrostatic recording processes, electrophotographic printing processes and the like, and demonstrate excellent resistance to damage by water and other environmental factors. The conductive substrate of the present invention includes a substrate layer with at least one surface thereof having a conductive layer formed thereover. The above mentioned conductive layer has as a principle component an acryl type copolymer formed from polymerizable vinyl monomer of the type shown in chemical structural diagram 1 below in an amount of 10 to 45% by weight of the acryl type copolymer, and at least one other type of polymerizable vinyl monomer, ##STR1## such that in chemical structural diagram 1, R.sub.1 represents a hydrogen atom or a methyl group, R.sub.2 represents an alkylene group, R.sub.3, R.sub.4 and R.sub.

Abstract: Residual ethylene oxide is removed from poly(ethylene oxide) by the steps of adding to particles of high molecular weight poly(ethylene oxide) a finely divided solid particulate material which is capable of coating the poly(ethylene oxide) particles and impeding their agglomeration under conditions of heating, heating the particles of poly(ethylene oxide) at a temperature of at least 40.degree. C. and preferably which is near their crystalline melting point, and maintaining the temperature for a sufficient time to reduce the ethylene oxide in the particles of poly(ethylene oxide) to ten ppm or less. In one embodiment, the poly(ethylene oxide) is heated by holding the particles in a heated enclosure; in another, it is heated as a slurry in a liquid medium; in yet another, it is heated by warm gas in a gaseously-fluidized bed; and in a fourth, it is heated by microwave radiation.

Abstract: Polycarbonate granules are produced by adding a solution of polycarbonate in an organic solvent to a suspension composed of water, an anti-solvent for polycarbonate and polycarbonate powder with stirring while evaporating and removing the organic solvent for polycarbonate added to the suspension. The procedure may be effected in the presence of a stabilizing agent for polycarbonate. The resulting polycarbonate granules are easy in handling, and free from fine powder, have high bulk density, large particle size and uniform quality, and can be directly molded.

Abstract: A process for substantially removing and recovering unreacted diene monomer from ethylene propylene diene monomer resin produced in a fluidized bed reactor by purging the resin with steam in a purging zone, the resin being introduced in the purging zone at a temperature above the temperature of the steam in the purging zone.

Abstract: A device for precipitating polymers from a liquid by at least one precipitant fluid includes a feed line, a nozzle plate having at least one outlet orifice for a polymer containing fluid with the outlet orifice communicating with the feed line, at least one nozzle for at least one precipitant fluid, the axis of which is arranged approximately perpendicularly to the axis of the outlet orifice, a precipitation chamber positioned on the side of the nozzle plate wherein at least one nozzle for at least one precipitant fluid is located, a discharge line for discharging a mixture which contains the precipitated polymer and a degassing chamber which is connected to the discharge line.

Abstract: The water absorption capacity of crosslinked, water-swellable polymers is improved by a process in which a water-containing, finely divided polymer gel having a solids content of from 20 to 65% by weight is treated with steam at not less than 50.degree. C., the solids content of the water-containing polymer gel increasing by not more than 30% by weight, and the polymer gel is then dried in a conventional manner.

Abstract: The 2-functional component of substituted phenol-aldehyde novolac resins is reduced. Epoxy novolac resins prepared from the novolac resin containing reduced quantities of 2-functional product exhibit increased Tg values when cured.

Abstract: The 2-functional component of substituted phenol-aldehyde novolac resins is reduced. Epoxy novolac resins prepared from the novolac resin containing reduced quantities of 2-functional product exhibit increased Tg values when cured.

Abstract: Low odor polyphenylene ether resin is produced by mixing a polyphenylene ether resin having an odoriferous content in water and bringing the mixture to a boil to distill a portion or all of the water.

Abstract: Phenol-aldehyde novolac resins having reduced quantities of 2-functional material are prepared by removing all or part of the 2-functional material from this product resulting from reacting phenol with an aldehyde. Epoxy novolac resins prepared from the novolac resin containing less 2-functional product exhibit increased Tg values when cured.

Abstract: This invention provides an improved process for producing a superabsorbent polymer with reduced residual monomer content which comprises partially drying a crosslinked, partially neutralized polymer gel, then raising the temperature of the gel using microwaves or RF radiation in the absence of circulating air and thereafter completing the drying.

Abstract: A photographic support consisting essentially of a substrate and a resin layer provided on the image forming side of the substrate, said resin layer comprising a specific titanium dioxide pigment and others. This photographic support is excellent in that it has a high brightness and a high apparent whiteness and stability of the apparent whiteness is good; printed image of high sharpness can be formed thereon: and occurrence of die lip stain at production is quite little and thus it has good surface property.

Abstract: Ethylene/.alpha.-olefin copolymers are prepared by catalytic dry-phase copolymerization of the monomers in a stirred or fluidized polymerization zone, transfer of the resulting mixture of solid copolymer and unconverted gaseous monomer into a let-down zone and separation of the mixture, after pressure reduction, into a gaseous phase and a solid phase, by a continuous process in which the solid phase is continuously flushed beforehand with gaseous ethylene and then flushed with a mixture of nitrogen and steam. The ethylene copolymers are very substantially free of residual monomers and odor and flavor substances.

Abstract: A method for producing an aqueous C.sub.2 -C.sub.8 olefin/maleic anhydride copolymer suspension is disclosed. The aqueous copolymer suspension is particularly suitable for use in applications such as fiber spinning syrups in which a copolymer in dry powder form is not needed.

Abstract: A method for purifying polyethyleneterephthalate reins by contacting the resins with an atmosphere containing carbon dioxide under supercritical conditions.

Abstract: Disclosed herein is a particulate polymer prepared by the agglomeration of polymer particles contained in a polymer latex. The particulate polymer is composed of primary particles having particle sizes of at least 20 .mu.m and/or secondary particles formed by the agglomeration of at least some of the primary particles and is in the form of a compact mass substantially free of voids. The particulate polymer is prepared by coagulating the polymer latex in the presence of a coagulant and an organic liquid having low solubility in water. The particulate polymer has a high bulk specific gravity and contains few fine particles. It is thus easy to handle and allows the consumption of energy to be reduced in the drying step.

Abstract: The present invention provides an antistatic composition comprising a binder, a cyclic phosphazene, and a salt that complexes with the cyclic phosphazene. The cyclic phosphazene has the general formula ##STR1## wherein x is 3 or 4.

Abstract: The 2-functional component of substituted phenol-aldehyde novolac resins is reduced. Epoxy novolac resins prepared from the novolac resin containing reduced quantities of 2-functional product exhibit increased Tg values when cured.

Abstract: A process for separating low molecular weight compounds from a crude polycaproamide melt comprises heat treating the melt in vacuo with superheated steam, in an extruder having a plurality of degassing zones, under precise conditions of temperature, pressure and configuration, such that the occurrence of side reactions and dehydration of the melt are substantially eliminated, the molecular weight of the polymer during the heat treatment in vacuo, during transport and subsequent processing remains substantially unchanged, a residual content of low molecular weight compounds of .ltoreq.1.8% is achieved, and the operating flexibility of the process is increased.

Abstract: A method for removing a tertiary halide from an olefin hydrocarbon stream which comprises contacting the hydrocarbon stream with activated alumina at a temperature of about -40.degree. to about 120.degree. C.

Abstract: A method for the production of a hydrophilic polymer having a small residual monomer content from a hydrated gel polymer, which method comprises drying said hydrated gel polymer by contact thereof with a gas containing at least steam and having a dew point in the range of 50.degree. to 100.degree. C. at a temperature in the range of 80.degree. C. to 250.degree. C., and a hydrophilic polymer obtained therefrom.

Abstract: Increased efficiency coagulation and washing of latex particles is achieved by coagulating the latex to form particle flocks by application of a combination of mechanical and thermal energy, with up to about 85% of the applied energy being thermal energy. The flocks are thereafter washed by passage in counter-current relationship with wash water. The invention is particularly useful in the coagulation of fluorocarbon latices generated by polymerization, particularly emulsion polymerization.

Abstract: A process to produce a free flowing fine polymer powder is provided. The process comprises the steps of: providing a polymer cement comprising a polymer either melt or dissolved in a solvent to form a polymer cement; dispersing an antiblocking agent within a stream consisting of steam to form atomization steam; atomizing the polymer cement; contacting the atomized polymer cement with the atomization steam; and recovering polymeric particles. Polymeric particles so prepared have an average particle size of between 100 and 1000 microns. In a preferred embodiment, the polymers produced are rubbery polymers which are free flowing.