Verfahren zum Nachschäumen von preexpandierten polyolefinischen Partikeln

PROCEDURE AND DEVICE FOR THE VORSCHAEUMEN OF PLASTICS

PROCEDURE AND DEVICE FOR THE VORSCHAEUMEN OF PLASTICS

PROCEDURE FOR THE PRODUCTION OF FLAME RESISTANT EXPAND-CASH STYRENE POLYMERS.

USE OF VORGESCHAUEMTE PROPYLENE RESIN PARTICLES DURING SHAPING PROCESSES.

Procedure for the production of expanded, synthetic, harzförmiger micro balls

Stares claw clutch

EXPANDING POLYMER BIT-PIECES

EXPANDED POLYOLEFIN PARTICLES

METHOD FOR EXPANDING AND DRYING EXPANDABLE MICROSPHERES

DEVICE FOR EXPANSION OF EXPANDABLE POLYMER BEADS

PROCESS FOR THE PREPARATION OF FOAMABLE POLYOLEFIN PARTICLES

PROCESS FOR THE PRODUCTION OF EXPANDED PARTICLES OF A POLYPROPYLENE RESIN

A process for the production of expanded particles, which comprises providing an aqueous dispersion containing expandable particles which are formed of a polypropylene resin and which contain a blowing agent and an expansion aid and maintained at a temperature higher than the softening point of the resin and under a pressurized condition, and subjecting the dispersion to a lower pressure so that the expandable particles are expanded. The expansion aid is organic or inorganic solids having a particle size of 0.1 to 150 .mu.m and a melting point higher than the temperature at which the expansion of the expandable particles is performed and serves to improve the expansion ratio.

PLASTIC FOAM CUP AND METHOD FOR PRODUCING IT

DIMENSIONALLY ACCURATE EXPANDED FOAM CASTING PATTERN

Procédé pour l'obtention de perles en polystyrène expansé

Procédé pour l'obtention de perles en polystyrène expansé

Automatische Klauenkupplung für Eisenbahnfahrzeuge

Procédé pour l'obtention de perles en polystyrène expansé

[...] DE [...][...] ET iNSTALLATION[...] DE [...] DE [...][...] LA MISE EN [...] DU.

PURIFY-HASTY SUDSY RESIN MATERIAL.

PROCESS AND INSTALLATION FOR THE MANUFACTURE OF EXPANDED PLASTICS

PROCESS FOR MAKING EXPANDED SYNTHETIC RESINOUS MICROSPHERES

Apparatus for pre-expanding and molding thermoplastic polymer particles

Expandable thermoplastic polymer beads are introduced into a tank and are agitated therein in a heated moisture-free condition. The beads are pressurized within the tank with a hot gaseous medium to soften them and are then subjected within the tank to a selected degree of vacuum to expand the beads or particles. The vacuum is removed and atmospheric pressure is re-established in the tank. The expanded hot moisture-free particles are introduced into a mold where they are fused into an integral mass, followed by cooling of the fused mass within the mold to form an outer skin on the mass. The fused mass is ejected from the mold.

EXPANSION OF EXPANDABLE SYNTHETIC RESINOUS MICROSPHERES

Fire retardant particulate expandable styrene polymers

Fine particulate expandable flame retardant styrene polymers having an improved minimum mold dwell time and reduced block shrinkage are prepared by: (a) mixing together styrene monomer or a mixture of styrene and a copolymerizable monomer with an organic halogen compound and an expanding agent in an aqueous dispersion; (b) adding before or during polymerization to the mixture of (a) from 0.0001 to 0.1% by weight of an expoxidation product of an aliphatic hydrocarbon of which the epoxidated aliphatic chain comprises from 6 to 18 C atoms, this epoxidation product being soluble in the monomers; (c) carrying out a polymerization in the aqueous suspension of (a) and (b) using radical forming initiators at temperatures of 80° C.-130° C. to form expandable particles; (d) pre-forming the expandable particles resulting from (c); ageing the pre-formed particles of (d); and (f) molding the pre-formed and aged particles of (e) in a pressure resistant mold.

Process for the production of expanded particles of a polypropylene resin

A process for the production of expanded particles, which comprises providing an aqueous dispersion containing expandable particles which are formed of polypropylene resin and which contain a blowing agent and an expansion aid and maintained at a temperature higher than the softening point of the resin and under a pressurized condition, and subjecting the dispersion to a lower pressure so that the expandable particles are expanded. The expansion aid is organic or inorganic solids having a particle size of 0.1 to 150 µm and a melting point higher than the temperature at which the expansion of the expandable particles is performed and serves to improve the expansion ratio.

WATER EXPANDED POLYSTYRENE PARTICLES

Verfahren und Vorrichtung zum Ausdehnen oder Schaeumen von Kunststoffkuegelchen,-perlen od.dgl.

VORRICHTUNG ZUM SCHAEUMEN VON TREIBMITTELHALTIGEN TEILCHEN AUS THERMOPLASTISCHEM KUNSTSTOFF

GESCHLOSSENER KREISPROZESS ZUR HERSTELLUNG VON EXPANDIERTEM POLYSTYROL-SCHAUMSTOFF.

PROCESS FOR CONTROLLING PEARL DIMENSIONS IN THE PREPARATION OF EXPANDABLE STYRENE POLYMERS BY SUSPENSION POLYMERIZATION

VINYLIDENE CHLORIDE COPOLYMER EXPANDABLE PARTICLES & IN-MOLD FOAM MOLDING BY USE THEREOF

PROCEDURE FOR THE PRODUCTION OF FLAME RESISTANT EXPAND-CASH STYRENE POLYMERS.

ADAPTIVE TAX PROCEDURE FOR THE SUDSY AND SINTERS OF PLASTIC.

PROCEDURE FOR THE BLISTER OF MICROSPHAEREN.

PROCEDURE FOR THE SUDSY AND SINTERS OF PLASTICS.

PROCEDURE FOR THE PRODUCTION BLOWING GRAPHITIC PARTICLE OF ABSTENTIONS OF EXPAND-CASH OF STYRENE POLYMERS

EXPANDABLE RESINOUS PARTICLES

STYRENE POLYMERS CONTAINING BLOWING AGENTS

PROCESS FOR THE PREPARATION OF EXPANDABLE POLYVINYLARENE PARTICLES

Process for the preparation of expandable polyvinylarene particles in which compact polyvinylarene particles are impregnated by an inorganic N2- and/or O2-containing gas at a temperature below 95 .degree.C and at a pressure of 100 to 2,000 kPa gauge.

POROUS POLYMER PARTICLES

Porous polyvinylarene particles having a apparent density do of 600 to 200 kg/m3, which particles contain a nucleating agent and 2.0 % by weight or less, based on the amount of polyvinylarene, of a volatile organic blowing agent. The invention also relates to a process for the preparation of these particles as well as to the use of these particles in the preparation of expanded particles and foamed articles.

PROCESS FOR PRE-EXPANDING THERMOPLASTIC RESIN PARTICLES

PURIFICATION, IMPREGNATION AND FOAMING OF POLYMER PARTICLES WITH CARBON DIOXIDE

A process for making high-purity foam moldings without the use of organic blowing agents involves the use of inorganic gases such as carbon dioxide, nitrogen, air and other pneumatogens. The process involves the simultaneous impregnation and purification of the polymers with or without foaming. If foaming is not done in the extractor, the polymeric particles can be foamed in pre-expanders or expanded and molded in downstream equipment.

Process for preparation of foamed polyvinylarene particles

PROCEDE POUR PREPARER DES PARTICULES EXPANSEES DE RESINE DE POLYOLEFINE RETICULEE

Procédé pour préparer des particules expansées de résine de polyoléfine réticulée. Il consiste à faire d'abord expanser des particules d'une résine de polyoléfine réticulée contenant un agent porogène jusqu'à un rapport moyen d'expansion de 3 à 9, puis, après avoir donné de l'aptitude à s'expanser aux particules ainsi préexpansées, à faire expanser ces particules préexpansées jusqu'à un rapport moyen d'expansion de 13 à 37, ce rapport moyen d'expansion etant base sur le volume initial des particules de résine non expansées. Industrie des matières plastiques.

EXPANSION OF THERMOPLASTIC POLYMER BEADS

PROCESS TO EXPAND YOU SIN SMALL OF A POLYMER AMOLECIVEL, AND DEVICE FOR USE IN THE EXPANSION

Expanded cross-linked polyethylene particle, a molded product thereof and the methods thereof

An expansion-molded product made from expanded cross-linked polyethylene particles each of which has an outer skin and inner cellular core, said outer skin each being fused and welded together to form an interfacial membrane whose average thickness is as thick as at least three times that of a cell membrane of the inner cellular core, is prepared by charging a lot of the particles into a mold, heating the particles therein to such an extent that the space among the particles is filled and then aging thus obtained molded product. The expanded particle each has a structure having an outer skin on an inner cellular core, the outer skin being as thick as at least three times cell membrane of the inner cellular core. The expandable particles are prepared by impregnating a foaming agent into the cross-linked polyethylene particles and heating so that the expandable particles are subjected to a step in which the foaming agent existing in the surface thereof is preferentially forced to evaporate ...

Method of expanding heat expandable thermoplastic elements with steam and a horizontal expander with a feed near the bottom for expanding the heat expandable element

The steam expander conveys the expanding heat expandable thermoplastic elements along a horizontal axis using a plurality of paddle frames. The paddle frames serve to agitate and tumble the elements during movement from an inlet to an outlet. At the same time, steam is injected into the housing of the expander to expand the elements. The expanded elements can be drawn off via a vacuum line to an overhead hopper or hoppers.

Manufacture of high-density foamed polymer

A method and apparatus are disclosed for the manufacture of foamed polystyrene particles of moderately great density, such as 3 to 25 lbs. per cubic foot (50 to 400 milligrams per cubic centimeter). Beads are fed by a constant-displacement auger to an expander vessel having the form of, in its lowest part, a cylinder with a vertical axis, and thereabove, of a frustrum of an inverted cone having a base angle of about 83 DEG to 70 DEG . Steam is supplied to the vessel in an appropriate, controlled manner. The vessel also contains stator bars, to break lumps and retard the rotation of the material in the vessel, and rotating bars, to provide the necessary agitation. Desirably, the equipment includes a discharge chute of adjustable location, to facilitate adjustment of the residence time and consequently of the density of the expanded beads being produced. With apparatus according to the invention, it is possible to obtain beads substantially uniformly expanded to a desired density within the ...

METHOD FOR THE EXPRESSION OF EXPANDABLE GRANULES OF THERMOPLASTIC MATERIALS IN PARTICULAR POLYSTYRENE

Method for the expansion of granules of thermoplastic material, particularly polystyrene. The discrete granules are fed into the upper end of a tower or drum and allowed to descend by gravity while under agitation. While so descending they are insufflated with jets of saturated or superheated steam which surrounds each granule and causes it to expand to a final density as low as 4 kg/m3. The granules may be preheated before insufflation with steam, as by entraining them in a stream of heated air which also deposits them into the top of a tower. Or they may be preheated by moving them in a layer between confronting runs of upper and lower foraminous conveyor belts while directing heated air through the layer. When an inclined drum is used the discrete granules are introduced into the elevated end of the rotating drum and agitated while being insufflated with steam dispersed into the drum in a large number of jets distributed in and along its axis of rotation.

Polypropylene resin pre-expanded beads, manufacturing method thereof and expansion-molding method using said beads

Expandable synthetic resinous thermoplastic particles, method for the preparation thereof and the application therefor

Resilient foam particles and moldings are obtained employing a lightly crosslinked polymer such as a styrene polymer with volatile fluid foaming agent that has low permeability through the polymer. Multiple expansion will permit low density particles for molding.

Process of combining an antistatic agent with beads of thermoplastic material

Schaeumendes und bzw. oder teilweise geschaeumtes Mittel aus thermoplastischem,organischem Polymere und Verfahren zur Herstellung desselben

TEILCHEN AUS STATISTISCHEN PROPYLEN-KOPOLYMEREN UND VERFAHREN ZU IHRER HERSTELLUNG.

Process for obtaining pearls of expanded polystyrene

Pearls of expanded polystyrene are made from granules containing a blowing agent by steam treating the granules at atmospheric pressure to expand them, maturing the expanded granules and then steam heating under greater than atmospheric pressure. The pearls may be subjected to a further maturing in air which is preferably slightly heated. The steam heating of the pearls under greater than atmospheric pressure may be repeated more than once, each treatment being separated by a maturing. The process may be carried out continuously or at fixed stations. The pearls obtained have an apparent density of less than 5 kgm./m.3 and can be agglomerated to produce plates or moulded pieces.

Production of porous shaped articles from thermoplastic materials

A process for the production of porous masses and shaped articles from polymeric resins consists in heating finely-grained resin containing an organic volatile liquid, which does not dissolve or only swells the resin and which has a lower boiling point than the softening point of the resin, in homogeneous dispersion, in moulds to temperatures above the boiling point of the liquid, the amount of resin-liquid dispersion being such that on foaming up it completely fills the moulds and exerts an excess pressure on the inner walls of the mould. Already foamed-up resin may be co-employed and the resin-liquid dispersion may be first incompletely foamed by heating. Specified resins are polystyrene (which may be dissolved in monostyrene), polyvinyl pyrrolidone (which may be mixed with monostyrene and subjected to polymerization conditions), and polymethyl methacrylate (containing its monomer), while petroleum ether, pentane, hexane, heptane, cyclopentane, cyclohexane, methanol, methylene chloride ...

PROCESS FOR MAKING EXPANDED SYNTHETIC RESINOUS MICROSPHERES

... 1342671 Expanded microspheres DOW CHEMICAL CO 28 May 1971 [28 May 1970] 17953/71 Headings C3C and C3P Expanded synthetic resinous microspheres are obtained by (1) depositing on a moving surface an exposed layer of expandable microspheres (prepared, for example, by suspension (co)polymerization in the presence of a volatile organic expanding agent), the deposition being effected from a dispersion of expandable microspheres in a non-solvent containing a flocculating agent for the expanded microspheres, (2) carrying the exposed layer through a zone in which the moving surface is heated from a location adjacent the surface and opposite from the microspheres, the heating being to a temperature and for a time to dry and expand the microspheres, a flowing gas being simultaneously contacted with the drying and expanding microspheres, and (3) removing the dried expanded microspheres from the moving surface. The flowing gas, e.g. hot air, is preferably brought into concurrent flow contact with the ...

IMPROVEMENTS IN OR RELATING TO FOAMED PLASTICS CUPS

... 1276723 Drinking vessels DART INDUSTRIES Inc. 19 May 1969 [20 May 1968] 25464/69 Heading A4A [Also in Divisions B5 and C3] A foamed plastics cup is formed of fused foamed plastics beads, and has a wall thickness which does not exceed twice the average diameter of the foamed beads. The cup has a lip portion 20 which is approximately twice the thickness 22 of the side wall and has an outwardly facing concave face 20. The plastics beads may be of polystyrene. A method of moulding cups according to the invention includes partially expanding foamed plastics beads and introducing them into a mould and then further expanding them to fill the mould and afterwards cooling the mould and removing the cup therefrom.

Procedure for the production of foamed polystyrene beads

WATER-FOAMED POLYSTYRENE PARTICLES

PROCEDURE FOR THE NACHSCHÄUMEN OF PREEXPANDIERTEN POLYOLEFINI PARTICLES

PROCEDURE FOR THE PRODUCTION OF EXPANDED ONE POLYVINYLARENPARTIKELN

Procedure for the production of foamed polystyrene beads

Polystyrene having high degree of expandability, and formulation having a highly-expandable polymer therein

Process for the preparation of expanded polyvinylarene particles

Porous polymer particles

ANTI-STATIC ARTICLES

Substantially static-free, cellular expanded or foamed thermoplastic cups or containers, and processes for the manufacture of these articles including the manufacture of intermediate materials suitable for use in such manufacture.

MULTI-FOAMING OF THERMOPLASTIC BEADS

A process is disclosed for rapidly molding articles from foamable beads comprising pre-expanding foamable beads containing an excess of a foaming agent with heat under conditions to form pre-expanded beads. The pre-expanded beads may contain sufficient residual amounts of foaming agent or additional foaming agent may be added to the pre-expanded beads and the beads then further expanded by slowly heating the beads to soften and allow the foamed beads to further expand.

PROPYLENE-BASE RANDOM COPOLYMER PARTICLES AND PRODUCTION PROCESS THEREOF

PROPYLENE-BASE RANDOM COPOLYMER PARTICLES AND PRODUCTION PROCESS THEREOF Disclosed herein are propylene-base random copolymer particles suitable for use in the production of pre-foamed particles. The copolymer particles are obtained by heating starting copolymer particles to the crystallization temperature thereof and then quenching them in a medium of (the crystallization temperature 30.degree.C) or lower. Processes for obtaining the copolymer particles are also disclosed. Pre-foamed particles produced using the copolymer particles contain large cells. They can thus provide foamed moldings which are substantially free of shrinkage and have good flexibility.

METHOD OF DIMENSIONALLY STABILIZING POLYSTYRENE PATTERNS AND THE LIKE

Abstract of the Disclosure A method is disclosed of making dimensionally stable, expanded polystyrene foam patterns comprising: (a) expanding a supply of beads comprised of polystrene and a thermally responsive expanding agent, the expansion being accomplished in one or more stages by use of a gaseous heating agent (steam) to define a fused pattern body of the expanded beads, and (b) subjecting the fused pattern body to subatmospheric pressure (in the range of 5-20" of Hg) for a period of about .5-6 hours but no more than sufficient to accelerate and complete the migration of the trapped expanding agent out of the pattern body. The expanding agent can be selected from the group consisting of various forms of pentane or butane.

PROCESS FOR PRODUCTION OF FOAMED ARTICLES IN MOLD OF POLYPROPYLENE RESINS

DIMENSIONALLY ACCURATE EXPANDED FOAM CASTING PATTERN

A method is disclosed for heating pre-expanded foundry pattern molding beads of polystyrene or the like in a stream of hot air to reduce the vapor-forming expansion agent content for the purpose of producing more dimensionally accurate, molded foam bead casting patterns.

MATTER IN POLYOLEFIN EXPANDED RESIN PARTICLES

a. Matiére en particules expansées en résine de polyoléfine. b. Ces particules expansées de résine de polyéthylène réticulé ont une forme sphérique, un diamètre moyen de 1,4 à 5,5 mm, un rapport moyen d'expansion de 18 à 37 et un coefficient de compression de 1,6 x 10**-3 à 4,0 x 10**-3. c. Utile comme matière de filtration et comme matière de remplissage pour des coussins. at. Polyolefin resin expanded particle material. b. These expanded crosslinked polyethylene resin particles have a spherical shape, an average diameter of 1.4 to 5.5 mm, an average expansion ratio of 18 to 37 and a compression coefficient of 1.6 x 10 ** - 3 to 4.0 x 10 ** - 3. vs. Useful as a filtration material and as a filling material for cushions.

METHOD FOR PRODUCING FOAMED PARTICLES OF A POLYMERIC MATERIAL.

Processos para a preparação de partìculas de polivinilareno expandidas e para preparar um artigo espumante

FORFARANDE FOR EXPANDERING AV MIKROSFERER

Porous polymer particles

Porous polyvinylarene particles having a apparent density do of 600 to 200 kg/m3, which particles contain a nucleating agent and 2.0% by weight or less, based on the amount of polyvinylarene, of a volatile organic blowing agent. The invention also relates to a process for the preparation of these particles as well as to the use of these particles in the preparation of expanded particles and foamed articles.

PROCESS FOR THE PREPARATION OF RADIATION-CROSSLINKABLE FOAMABLE POLYOLEFIN PARTICLES

Process for the production of expanded particles of a polypropylene resin

A process for the production of expanded particles, which comprises providing an aqueous dispersion containing expandable particles which are formed of polypropylene resin and which contain a blowing agent and an expansion aid and maintained at a temperature higher than the softening point of the resin and under a pressurized condition, and subjecting the dispersion to a lower pressure so that the expandable particles are expanded. The expansion aid is organic or inorganic solids having a particle size of 0.1 to 150 µm and a melting point higher than the temperature at which the expansion of the expandable particles is performed and serves to improve the expansion ratio.

Pre-expanded particles of propylene resin

A pre-expanded particle of a propylene resin having two melting temperatures as determined by DSC, the heat of fusion for the peak based on the higher melting temperature being 0.5 to 2.3 cal/g. By using the pre-expanded particles of the propylene resin of the invention, foamed articles having excellent surface appearance, small dimentional shrinkage can be easily obtained without the procedure for giving the internal pressure.

HERSTELLUNGSVERFAHREN EINES EXPANSIONSFORMTEILES AUS POLYPROPYLENHARZ.

Expanded particulate material of polyolefin resin

Improvements in the manufacture of porous articles from polymeric resins

Porous shaped articles are produced from a polymeric resin by introducing into an enclosing mould a finely divided resin containing a volatile organic solvent having a boiling point lower than the softening point of the resin and heating to above the softening point to expand the resin and fill the mould which permits the escape of gases, but retains the resin, the solvent-containing resin being obtained by incomplete evaporation of the solvent from the solvent-resin solution. Specified resins are chlorinated polystyrene and poly-N-vinyl carbazole, preferably having a k-value of at least 30. Specified solvents are benzene, toluene, p-xylene, methylene chloride and cyclononane for the carbazole and methylene chloride, chloroform, carbon tetrafluoride and ethylene chloride for the chlorinated polystyrene. Pre-expanded particles of a solvent-containing resin may be used. The process details are the same as those described in the parent Specification.

Expanding resin particles

The invention relates to a process of expanding styrene beads which comprises expanding said beads in the presence of a surfactant having a HLB value of 3 to 18 and showing a surface resistance less than 1014 OMEGA /cm. By the process, blocking of beads is prevented, antistatic effect can be given to the shaped article and saving of steam used in the course of expanding is achieved.

PROCEDURE FOR COMBINING ANTISTATIC MEANS WITH THERMOPLASTIC BEADS.

CLOSED CYCLIC PROCESS FOR THE PRODUCTION OF EXPANDED POLYSTYRENE FOAM MATERIAL.

PROCEDURE FOR THE PRODUCTION OF EXPAND-CASH POLY (VINYLAREN) PARTICLES

Procedure for the production of cellular plastic beads from polystyrene

VERFAHREN UND VORRICHTUNG ZUM VORSCHAEUMEN VON KUNSTSTOFFEN

Expanded polyolefin particles

Expanded particles of polyolefin resin and process for producing same

The mixture of water and the polyolefin resin particles impregnated with a volatile blowing agent are released from the interior of the pressure-resistant container under a constant temperature and constant pressure preferably keeping the partial pressure of the blowing agent constant, through at least one orifice having an area of 0.07 to 300 mm 2 , into a low-pressure zone. This invention gives various advantages when applied to the practical process resulting in expanded particles with superior properties which are free of blocking and remarkably uniform in the degree of expansion, and are useful for molding.

Process of combining an antistatic agent with beads of thermoplastic material

Expanded cellular or foamed thermoplastic cups and containers commonly are readily statically charged and this causes problems, particularly in drink dispensing means. <??>Articles of such material can be made substantially static free by use of a selected surface active agent or emulsifier which may be applied to the surface of the article or to the beads of thermoplastic material from which the article is made. <??>In a process of combining anti-static agent and thermoplastic material, an anti-static agent, which may be liquid or solid, is misted, atomised or vapourised for coating beads of a thermoplastic material, the beads at the coating stage being unexpanded or pre-expanded.

Process for the production of expanded particles of a polypropylene resin

A process for the production of expanded particles, which comprises providing an aqueous dispersion containing expandable particles which are formed of a polypropylene resin and which contain a blowing agent and an expansion aid and maintained at a temperature higher than the softening point of the resin and under a pressurized condition, and subjecting the dispersion to a lower pressure so that the expandable particles are expanded. The expansion aid is organic or inorganic solids having a particle size of 0.1 to 150 μm and a melting point higher than the temperature at which the expansion of the expandable particles is performed and serves to improve the expansion ratio.

Process for producing expanded particles of a polyolefin resin

Expanded particles of polyolefin resin and process for producing same

ABSTRACT The mixture of water and the polyolefin resin particles impregnated with a volatile blowing agent are released from the interior of the pressure-resistant container under a constant temperature and constant pressure preferably keeping the partial pressure of the blowing agent constant, through at least one orifice having an area of 0.07 to 300 mm2, into a low-pressure zone. This invention gives various advantages when applied to the practical process resulting in expanded particles with superior properties which are free of blocking and remarkably uniform in the degree of expansion , and are useful for molding.

Pre-expanding process and apparatus for the same

A process for preparing pre-expanded particles of a thermoplastic resin which comprises; heating under an elevated pressure an aqueous dispersion comprising thermoplastic resin particles containing a volatile foaming agent and an aqueous medium in a pressure vessel; releasing the dispersion from the pressure vessel into a space within a sealed low-pressure vessel wherein the pressure is lower than that in the pressure vessel, whereby expanding the thermoplastic resin particles to give pre-expanded particles; and simultaneously recovering the foaming agent volatilized from the thermoplastic resin particles by discharging the foaming agent out of the space in the low-pressure vessel with controlling the pressure in the low-pressure vessel to substantially a given pressure. According to the process, the release of the volatile foaming agent into the air is prevented.

Process for the production of expanded particles of a polymeric material

A process is disclosed for the production of expanded particles of polymeric material wherein unexpanded particles of the material are contacted with a nitrogen-containing inorganic gas under a first pressure condition to impregnate the particles with the gas. The gas impregnated particles are heated to a temperature higher than the softening point of the material, and dispersed into a liquid medium. The resulting dispersion is subjected to a lower pressure to expand the particles. The expanded particles may be used as prefoamed particles for the molding of foamed articles.

Patent JPH0546852B2

Method for pre-expanding thermoplastic resin particles

Pre-expanded particles of propylene resin

Abstract of the Disclosure A pre-expanded particle of a propylene resin having two melting temperatures as determined by DSC, the heat of fusion for the peak based on the higher melting temperature being 0.5 to 2.3 cal/g. By using the pre-expanded particles of the propylene resin of the invention, foamed articles having excellent surface appearance, small dimentional shrinkage can be easily obtained without the procedure for giving the internal pressure .

Pre-expansion method of polyolefin resin particles

Patent FR2400423B1

Expanded cross-linked polyethylene particle, a molded product thereof and the methods thereof

Abstract An expansion-molded product made from expanded cross-linked polyethylene particles each of which has an outer skin and inner cellular core, said outer skin each being fused and welded together to form an interfacial membrane whose average thickness is as thick as at least three times that of a cell membrane of the inner cellular core, is prepared by charging a lot of the particles into a mold, heating the particles therein to such an extent that the apace among the particles is filled and then aging thus obtained molded product. The expanded particle each has a structure having am outer skin on an inner cellular core, the outer skin being as thick as at least three times cell membrane of the inner cellular core. The expandable particles are prepared by impregnating a foaming agent into the cross-linked poly-ethylene particles and heating so that the expandable par-ticles are subjected to a step in which the foaming agent existing in the surface thereof is preferentially forced to evaporate.

Process for producing expanded particles of a polyolefin resin

A process for the preparation of expanded particles in which a mixture of water and of polyolefin resin particles, impregnated with a volatile blowing agent, is released from the interior of a pressure-resistant container under a constant temperature and constant pressure, preferably keeping the partial pressure of the blowing agent constant, through at least one orifice having an area of 0.07 to 300 mm 2 , into a low-pressure zone. This invention gives various advantages when applied industrially, giving expanded particles with superior properties which are free of blocking, showing a remarkably uniform degree of expansion, and being useful for molding.

Pre-expanded polyolefin particle

Method of preparing expandable polystyrene

A process for the expansion of an expandable, polymeric, bead material by exposing the bead material to steam at an elevated temperature, to effect the expansion of the bead material into a polymeric bead material form, while tumbling the bead material during expansion to prevent fusion, the improvement which comprises: employing as a lubricant for the bead material a lubricant material which, on exposure to the steam and prior to the end of the expansion of the bead material, is changed in lubricant characteristics, to provide an expanded, polymeric foam bead material having a reduced surface lubricity.

Polymeric articles having antistatic properties and methods for their manufacture

An article comprised of a polymeric material bearing a coating. The coating comprises a residual layer formed by applying and allowing to dry a mixture containing from about 7.5 to about 23.5 weight percent of a humidity sensitive antistatic surfactant compound and from about 10 to about 30 weight percent of a water soluble ink. The article possesses an electrostatic potential of from about -5 to about +5 kilovolts as measured at one inch from the coating. A process for producing a formed article which is relatively free from the effects of static electricity. The process includes the steps of topically applying a mixture comprising a humidity sensitive antistatic surfactant compound to a stock comprising a foamed polymeric material, conditioning the foam stock in a humidity-controlled environment effective to reduce electrostatic potential of the stock to between from about -5 to about +5 kilovolts, and thereafter forming the article from the conditioned foam stock. The polymeric material may comprise polystyrene and the water soluble ink may comprise a mixing white ink. The humidity sensitive surfactant is preferably comprised of a mixture of sodium alkyl sulfonates consisting essentially of sulfonates having the molecular formulas C 10-18 H 21-39 SO 3 Na.

Process for production of foamed molded articles of polypropylene resin

내용 없음. No content.

Process for the preparation of expanded polyvinylarene particles

600 내지 200 kg/m 3 범위의 겉보기 밀도 d o 로 예비-팽창된 폴리비닐아렌 입자가 무기 기체로 함침되고, 이렇게 수득되는 함침 입자가 d o 보다 적어도 3배 감소한 겉보기 밀도로 팽창되는 팽창 폴리비닐아렌 입자의 제조방법. 겉보기 밀도, 폴리비닐아렌, 팽창, 함침

Method for producing pre-expanded polypropylene resin molded product

Process and apparatus for forming lightweight inorganic aggregate

A method and apparatus for expanding particles of a lightweight aggregate material are disclosed. The apparatus comprises a housing having an upper chamber separated from a lower chamber by a partition having a plurality of openings. Hot air is introduced into the lower chamber and flows through the partition to fluidize particles introduced into the upper chamber. Means are provided for independently regulating the velocity of air through separate sections of the partition. Particles are introduced at the inlet end of the upper chamber. The particles are fluidized and transported toward the outlet end of the upper chamber by the air flow. The temperature of the air flow causes the particles to expand and become lighter. The velocity of the air flow through separate sections of the partition is adjusted to maintain uniform fluidization of the particle bed in the upper chamber.

Method and apparatus for expanding loose fill material, such as expandable polystrene pellets

A compact, self-contained apparatus and method for expanding loose fill foam material for packaging includes an eductor having a fan, a venturi chamber, and a wire mesh cage arrangement for automatically feeding expandable loose fill material to a hopper. The loose fill material is then uniformly fed through the hopper by air pressure in conjunction with gravity to an expansion chamber. The expansion chamber includes a stepped conveyance platform disposed over a stepped steam chamber, and a track arrangement for simultaneously conveying and tumbling the loose fill material across each conveyance platform step. A condensing unit disposed above the expansion chamber removes excess moisture from the expansion chamber and provides warm dry air to a discharge housing from which the expanded loose fill material is discharged from the expansion chamber.

Porous polymer particles

입자가 기핵제 및 폴리비닐아렌의 양을 기준으로, 휘발성 유기 발포제 2.0 중량% 이하를 함유하는, 겉보기 밀도 d o 600 내지 200 kg/m 3 을 가지는 다공성 폴리비닐아렌 입자. 본 발명은 또한 이러한 입자의 제조방법 및 팽창 입자 및 발포체의 제조에서 이들 입자의 용도에 관한 것이다. 팽창, 폴리비닐아렌, 겉보기 밀도, 발포체

Method for producing expandable styrene polymers containing exfoliated graphite particles

The invention relates to a method for the production of expandable styrene polymers containing graphite particles by polymerizing styrene in an aqueous suspension in the presence of defoliated graphite particles with a density of less than 1.5 g/cm3.

Method of manufacturing graphite particle-containing expanding polystyrene

FIELD: polymer materials. SUBSTANCE: styrene or its mixture with comonomers are subjected to polymerization in aqueous suspension in presence of foaming agent and swollen graphite compound. EFFECT: simplified technology and improved heat-retention and antistatic properties of polystyrene foamed plastics. 6 cl, 2 ex УЗзЗб$ ССС ПЧ сэ (19) (11) (13) КО (51) МПК? 2 223 984 С2 С 08 4 9/20, С 08 Е 25/04, С 08 К 3/04 РОССИЙСКОЕ — АГЕНТСТВО ПО ПАТЕНТАМ И ТОВАРНЫМ ЗНАКАМ 12 ОПИСАНИЕ ИЗОБРЕТЕНИЯ К ПАТЕНТУ РОССИЙСКОЙ ФЕДЕРАЦИИ (21), (22) Заявка: 2001105911/04 , 12.07.1999 (72) Изобретатель: ГЛЮК Гуискард (ОЕ) (24) Дата начала действия патента: 12.07.1999 (73) Патентообладатель: БАСФ АКЦИЕНГЕЗЕЛЬШАФТ (ОЕ) (30) Приоритет: 27.07.1998 ОЕ 198 33 664.0 (74) Патентный поверенный: (43) Дата публикации заявки: 27.10.2003 Квашнин Валерий Павлович (46) Дата публикации: 20.02.2004 (56) Ссылки: ВЕ 19517774 АЛ, 21.11.1996. ЕР 0245779 АЛ, 19.11.1987. М/О 9851734 А\Л, 19.11.1998. РЕ 29616362 11, 19.12.1996. КУ 2096427 С1, 20.11.1997. (85) Дата перевода заявки РСТ на национальную фазу: 27.02.2001 (86) Заявка РСТ: ЕР 99/04867 (12.07.1999) (87) Публикация РСТ: У\о —00/06635 (10.02.2000) (98) Адрес для переписки: 103064, Москва, ул. Казакова, 16, НИИР Канцелярия "Патентные поверенные Квашнин, Сапельников и партнеры", пат.пов. —В.П.Квашнину (54) СПОСОБ ПОЛУЧЕНИЯ СОДЕРЖАЩЕГО ЧАСТИЦЫ ГРАФИТА РАСШИРЯЮЩЕГОСЯ ПОЛИСТИРОЛА (57) Технической задачей является разработка Изобретение относится к способу упрощенного способа получения получения расширяющегося полистирола, расширяющегося полистирола, содержащего содержащего вспученное соединение вспученное соединение графита, а также графита, и пенопласта на его основе. Способ улучшение теплоизоляционных и заключается в полимеризации стирола или антистатических СВОЙСТВ пенопластов, его смеси с сомономерами в водной получаемых на основе этого полистирола. 3 суспензии в присутствии вспенивающего с. из з.п. ф-лы. агента и вспученного соединения графита. 2223984 С2 ...

Vinylidene chloride type resin expandable particles, foam particles, in-mold foam molding by use thereof and process for producing them

The present invention discloses a vinylidene chloride resin type in-mold foam molding having a broad cross-sectional area and a free shape, which is useful as thermal insulating plate materials or as anti-shock molded vessels, and also to foam particles or expandable particles which are convenient for the preparation thereof. The present invention is also related to a series of advantageous foaming techniques for completion of such a molding. The above foam molding can be prepared by contacting fine particles of a non-crystalline vinylidene chloride type resin obtained generally by suspension polymerization with a volatile organic blowing agent thereby impregnating the resins with the blowing agent to form expandable resin particles, which are in turn subjected to expansion as such, or after forming into pre-expanded foam particles including expandable gas therein, by filling in a mold cavity which can be closed but not sealed, under heating to form a molding through a mutual fusion between the expanded particles.

An expanded cross-linked polyethylene particle and methods to produce molded products thereof

Improvements to processes for obtaining expanded polystyrene beads

ANTI-AGGLOMERATION COATING FOR POLYSTYRENE BEADS

L'invention concerne l'industrie des polymères cellulaires. Procédé d'imprégnation de perles de polystyrène par un agent de gonflement dans un système aqueux contenant un complexe d'aluminium et de collagène de poids moléculaire élevé, d'au moins 60 000, ledit complexe agissant comme agent de suspension des perles dans le milieu aqueux et formant sur les perles, après leur égouttage, un dépôt conférant un effet anti-agglomérant aux particules pré-expansées dérivées desdites perles. Application à la fabrication d'articles en polystyrène mousse, par moulage à chaud des particules pré-expansées pourvues du revêtement du complexe. The invention relates to the cellular polymer industry. A method of impregnating polystyrene beads with a swelling agent in an aqueous system containing a complex of aluminum and high molecular weight collagen, of at least 60,000, said complex acting as an agent for suspending the beads in the medium aqueous and forming on the beads, after draining them, a deposit conferring an anti-caking effect on the pre-expanded particles derived from said beads. Application to the manufacture of articles in foam polystyrene, by hot molding of the pre-expanded particles provided with the coating of the complex.

Manufacture of molded articles from expandible styrene polymer

ABSTRACT OF THE DISCLOSURE: Expandible particles of styrene polymers are pre-pared by a process in which the polymerization of styrene, or of mixtures of styrene and monomers copolymerizable with it, and/or treatment of the expantible particles prior to expansion thereof, are (is) carried out in the presence of dimers or trimers of unsaturated fatty acids or their esters with C1 - C18 alcohols.

VINYLIDENE CHLORIDE-TYPE EXPANDABLE PARTICLES, FOAM PARTICLES, MOLDED FOAM PRODUCT AND PROCESSES FOR PREPARING THE SAME

PARTICULES EXPANSABLES EN CHLORURE DE VINYLIDENE. ELLES COMPRENNENT DES PARTICULES EN RESINE DE TYPE CHLORURE DE VINYLIDENE SENSIBLEMENT NON CRISTALLINES, AVEC UNE DIMENSION MOYENNE DE PARTICULES COMPRISE ENTRE 0,05 ET 5MM, QUI SONT LISSES SUR LES SURFACES DES PARTICULES, SANS INTERSTICES, ET QUI SONT IMPREGNEES D'UN AGENT POROGENE ORGANIQUE QUI EST VOLATIL. INDUSTRIE DES MATIERES PLASTIQUES. EXPANDABLE VINYLIDENE CHLORIDE PARTICLES. THEY INCLUDE SENSITIVELY NON-CRYSTALLINE VINYLIDENE CHLORIDE-TYPE RESIN PARTICLES, WITH AN AVERAGE PARTICLE SIZE BETWEEN 0.05 AND 5MM, WHICH ARE SMOOTH ON THE SURFACES OF THE PARTICLES, WITHOUT INTERSTICES, AND WHICH ARE IMPREGENTED ORGANIC THAT IS VOLATILE. PLASTICS INDUSTRY.

Process for the production of porous moldings from thermoplastics

Fixed-jaw railway car coupler

EXPANDABLE VINYLIDENE CHLORIDE RESIN EXPANDABLE PARTICLES, FOAMED PARTICLES, FOAM MOLDED PRODUCT AND PROCESSES FOR THEIR PREPARATION

Improvements to processes for the treatment of expandable polymer particles

Patent FR2255319B1

Patent FR2368513B2

Process for producing prefoamed polymer particles

Prefoamed polymer particles having excellent moldability are produced by a process comprising a step (impregnating step) of impregnating carbon dioxide or carbon dioxide and a volatile blowing agent in polymer particles, a step (dispersing step) of dispersing the polymer particles into a dispersion medium in a sealed vessel, a step (heating step) of heating the polymer particles to a temperature higher than the softening point of said polymer particles, and a step (releasing step) of opening one end of said vessel and simultaneously releasing the polymer particles and dispersion medium from inside the vessel to an atmosphere held at a pressure lower than that of the vessel. In this process, the impregnating step, dispersing step and heating step need not be altogether effected separately. These steps can be performed simultaneously in one and the same vessel.

PROCEDURE AND EQUIPMENT FOR THE EXPANSION OF POLYMER MATERIAL IN SMALL PIECES

Process for production of expansion-molded articles of linear low density polyethylene resins

Process for the preparation of expandable polyvinylarene particles

RAILWAY CLUTCH OF THE TYPE WITH A FIXED CLAW, WITH DEVICE TO MAINTAIN THE CONNECTED CONDITION DESPITE IMPACT.

Patent JPS6230219B2

Pre-expanded particle of polyolefine and process for preparing the same

A pre-expanded particle suitable for foaming in a mold comprising polyolefin which has a characteristic property that an inclination of slope line obtained on a graph when logarithmic values of melt tension of the polyolefin are plotted as ordinate and reciprocals of absolute temperature at which the melt tension is measured are plotted as abscissa is less than 1,500 is provided. A foamed article produced from the pre-expanded particles has an excellent appearance, a flat surface and good mechanical strength, and is useful for wrapping material, insulating material, a container or a fender of cars. A process for preparing the above-mentioned pre-expanded particles is also disclosed.

FOERFARANDE FOER FRAMSTAELLNING AV EXPANSIONSFORMADE PRODUKTER AV LINEAERA LD-POLYETENER I EN FORM.

Anti-static material and process

USE OF PREVIEWED PROPYLENE RESIN PARTICLES IN MOLDING PROCESSES.

Device for expansion of expandable polymer beads

An apparatus is provided wherein large low-density interlocking particles are made by expanding thermoplastic polymer beads containing a normally liquid organic blowing agent. The beads are expanded by heating to the temperature of expansion with steam in a rotating tube. Gentle agitation is provided by a combination of the tumbling action of the rotating tube and the action of the steam rising through the expanding beads. The resultant uniformly expanded particles are not crushed or shredded. The particles are suitable for use in loose-fill packaging of shock-sensitive materials.

METHOD FOR PRODUCING FOAMED MOLDED OBJECTS FROM POLYPROPYLENE RESIN.

Process for the production of foam bodies from linear low density polyethylene.

Expandable synthetic resinous thermoplastic particles,method for the preparation thereof and the application therefor

Patent FR2197934A1

EXPANSION FORM

METHOD FOR PRODUCING EXPANDABLE POLY (VINYLARENE) PARTICLES

Manufacturing process of pre-expanded polyolefin resin particles.

Process for production of expansion-molded article in a mold of linear low density polyethylene resins

ABSTRACT The present invention provides a process for production of expansion-molded articles of linear low density polyethylene resin which comprises compressing pre-expanded linear low density polyethylene resin beads having two melting points when measured by differential scanning calorimetry, the lower melting point and the higher melting point being designated TML and TMH respectively, at a temperature between the two melting points, the peak fusion area at TML being designated AL and the peak fusion area at TMH being designated AH, and satisfying: 5% ? AH/AL ? 80% under gaseous pressure, filling a mold with said compressed beads, said mold being capable of being closed but not sealable, then venting the mold and, heating and fusing with steam in such a state that the compressive rate of the pre-expanded beads immediately before heating with steam compared to the original pre-expanded beads is maintained at 5 to 60%, thereby to produce the molded article in the shape of the mold. These molded articles of linear low density polyethylene have a minimized dimensional shrinkage rate (good dimensional accuracy) and excellent fusion rate and surface appearance and can be produced at a high rate.

Method of expanding particle of expandable lightweight aggregate material

(57)【要約】本公報は電子出願前の出願データであるた め要約のデータは記録されません。

Patent FR2112374B1

Method for partially expanding plastic beads in a rotating pan

METHOD FOR THE PRODUCTION OF EXPANDED POLYVINYLENE PARTICLES

Process for molding expandable thermoplastic material

Molded articles are made from expandable thermoplastic resin material by pre-expanding the thermoplastic material in particulate or bead form containing as the principal expanding agent a liquid hydrocarbon by contact with steam until the desired degree of expansion is obtained, heating the beads in a stream of substantially dry, hot gas at a temperature above the boiling point of the hydrocarbon but below the fusion temperatures of the thermoplastic material while agitating the beads to prevent agglomeration upon softening until substantially all of the moisture is removed from the surfaces of the pre-expanded beads, and molding the article from the heated pre-expanded beads by placing them in a closed mold and heating them to a temperature above their fusion temperature, the temperature of the thermoplastic material being continuously maintained above the boiling point of the expanding agent from the time the beads are pre-expanded until they are molded into the shaped article.

Device for foaming blowing agent-containing particles made of thermoplastic material

Porous polymer particles

Porøse polyvinylarenpartikler med en tilsynelatende densitet dpå 600 til 200 kg/m, og som inneholder et kjernedannende middel og 2,0 vekt% eller mindre, basert på mengden av polyvinylaren, av et flyktig organisk esemiddel. Oppfinnelsen angår også en prosess for fremstilling av disse partiklene, samt anvendelse av disse partiklene i fremstillingen av ekspanderte partikler og skummede gjenstander.

METHOD FOR THE PRODUCTION OF EXPANDABLE STYRENE POLYMERISTS CONTAINING EXPANDABLE GRAPHITE PARTICLES

Process for preparation of expandable polyvinylarene particles

一种制备可发泡性聚乙烯基芳烃粒子的方法，其中在低于95℃的温度和在表压为100～2000千帕的条件下用无机的含N 2 和/或O 2 的气体来浸渍紧密的聚乙烯基芳烃粒子。

Closed circuit process for the production of expanded polystyrene foam

A closed circuit process for the production of expanded polystyrene foam is described, comprising the steps of: (a) pre-expanding raw polystyrene beads containing a blowing agent in a pre-expansion vessel; (b) storing the beads in one or more closed storage containers to allow the expanded beads to return to substantially atmospheric pressure; (c) molding the expanded beads to a desired configuration in a closed mold with steam; and (d) removing the thus-formed article from the mold and placing such in an aging room, wherein at each stage the blowing agent released from the beads is recovered, separated from any residual steam by means of a condensing system, and introduced into the burner of a steam generator, thereby serving as fuel for the process.

Improvements in the procedures for the obtaining of expansioned polystirene pearls. (Machine-translation by Google Translate, not legally binding)

Improvements in the processes for obtaining expanded polystyrene beads, characterized in that they consist of pre-expanding the granules containing a bloating agent at atmospheric pressure by subjecting them to a steam treatment and then, after conditioning, in autoclaving. by steam (Machine-translation by Google Translate, not legally binding)

Process for the preparation of expanded polyvinylarene particles

Sposób wytwarzania spienionych, porowatych cz astek poliwinyloarenowych, zgodnie z wyna- lazkiem charakteryzuje si e tym, ze obejmuje etapy a) wst epnego spieniania niespienionych cz astek poliwinyloarenowych, które zosta ly nasycone srodkiem porotwórczym do g esto sci pozornej d o w za- kresie 600-200 kg/m 3 , do utworzenia porów w tych cz astkach, przy czym pory maj a tak a wielkosc, ze nadci snienie gazu nieorganicznego, który mo ze zosta c wprowadzony do porów tych cz astek, wynosi 200-1000 kPa, nasycania nieorganicznym gazem porów wst epnie spienionych cz astek, przy czym cz astki poliwinyloarenowe nasyca si e gazem nieorganicznym przez ekspozycj e ich na gaz w tempera- turze w zakresie od 0 do 95°C tak, ze w porach cz astek porowatych uzyskuje si e nadci snienie 100 do 1500 kPa, oraz c) spieniania cz astek z etapu b) do utworzenia spienionych cz astek poliwinyloare- nowych do g esto sci pozornej co najmniej trzy razy ni zszej ni z d o , przy czym nasycone cz astki spienia sie przez ekspozycj e ich na dzia lanie pary o temperaturze 100 do 168°C przy nadci snieniu w zakresie od 0 do 600 kPa. Przedmiotem wynalazku jest tak ze zastosowanie spienionych, porowatych cz astek poliwinyloarenowych, wytworzonych omawianym sposobem, do wytwarzania wyrobu piankowego. PL PL PL PL

Process for pre-expanding thermoplastic resin particles

Abstract of the Disclosure 1. In a process for pre-expanding thermoplastic resin particles which comprises releasing into a low pressure zone a mixture of water and thermoplastic resin particles containing a volatile blowing agent, the mixture being maintained at an elevated temperature under pressure in a pressure vessel, the improvement which comprises releasing the mixture through a plurality of orifice plates in series to the direction of releasing the mixture. According to the process of the present invention, the average cell diameter of the obtained pre-expanded particles is larger than that of the pre-expanded particles obtained by means of conventional methods. Therefore, the molded articles prepared from the pre-expanded particles according to the present invention are small in shrinkage and excellent in surface appearance, and are utilizable for use of shock absorbing, wrapping materials or structural materials such as impact-absorbing materials for cars (for example, a car bumper), which requires excellent dimentional precision and heat insulating builting materials.

Process and apparatus for the manufacture of expanded plastics materials

The present invention provides an apparatus for the manufacture of pre-expanded particles, which comprises in combination a heat-insulated resonating cavity, with a high-frequency electromagnetic source of energy, a ferrite circulater, a wave guide, an Archimedes screw for the introduction of the plastics material to be pre-expanded, a pump for regulating the feed of polar liquid and a device for extracting the pre-expanded particles. The present invention provides also a process for the pre-expansion of particles of plastic material using said apparatus.

Expandable synthetic resinous thermoplastic particles, method for the preparation thereof and the application therefor

Resilient foam particles and moldings are obtained em­ ploying a lightly crosslinked polymer such as a styrene pol­ ymer with volatile fluid foaming agent that has low permeability through the polymer. Multiple expansion will permit low density particles for molding.

Process for the production of flame-retardant, porous, cell-like molded bodies

Process for production of foamed molded articles of polypropylene resin

Apparatus for thermoplastic resins pre-expanding process

A process and apparatus for preparing pre-expanded particles of a thermoplastic resin which comprises; heating under an elevated pressure an aqueous dispersion comprising thermoplastic resin particles containing a volatile foaming agent and an aqueous medium in a pressure vessel; releasing the dispersion from the pressure vessel into a space within a sealed low-pressure vessel wherein the pressure is lower than that in the pressure vessel and the space is sealed with an aqueous medium which exists in the lower portion of the vessel and communicates with the outside of the vessel, whereby expanding the thermoplastic resin particles to give pre-expanded particles; and sinking the resulting pre-expanded particles under the aqueous medium by means of a rotary impeller provided in the pressure vessel so that the pre-expanded particles are taken out of the low-pressure vessel through the aqueous medium towards the outside of the vessel, while recovering the foaming agent volatilized from the thermoplastic resin particles by discharging the foaming agent out of the space in the low-pressure vessel with controlling the pressure in the low-pressure vessel to substantially a given pressure. According to the process, the release of the volatile foaming agent in the air is prevented, the productivity is increased and extraneous matters on the pre-expanded particles are removed.

Polypropylene resin pre-expanded beads, manufacturing method thereof andexpansion-molding method using said beads

ABSTRACT OF THE DISCLOSURE The present invention provides polypropylene resin pre-expanded beads formed by shrinking polypropylene resin pre-expanded beads originally having a bulk density of not higher than 0.0930 g/cc to give them a bulk volume ratio of 10 - 75 % at the normal temperature and the normal pressure, a manufacturing method thereof and an expansion-molding method with the aforementioned pre-expanded beads. According to this invention, it is possible to greatly reduce storing and transporting costs per unit weight of pre-expanded beads.

Process for preparing expandable styrene polymers containing graphite particles

eÜen se t²k zp sobu p° pravy expandovateln²ch styrenov²ch polymer , obsahuj c ch stice grafitu, polymerac styrenu ve vodn suspenzi v p° tomnosti stic expandovan ho expandovateln ho grafitu o hustot menÜ ne 1,5 g/cm.sup.3.n..\

Process for the preparation of expandable polyvinylarene particles

Process for the preparation of expandable polyvinylarene particles in which compact polyvinylarene particles are impregnated by an inorganic N2- and/or O2-containing gas at a temperature below 95 °C and at a pressure of 100 to 2,000 kPa gauge.

Expanded particulate material of polyolefin resin

Expanded particles of a crosslinked polyolefin resin, each particle with uniformly spherical shape, having an average diameter of 1.4 to 5.5 mm, an average expansion ratio of 18 to 37 and specific compression coefficient of 1.6 × 10 -3 to 4.0 × 10 -3 , are found to be produced by two-step foaming operations. They are useful for various purposes such as filtrating material, fillers in stuffed specimens and, especially for preparation of molded articles having constricted portions, giving excellent moldings having smooth surface without failure at corner or edge portions.

Apparatus and process for making particles from pre- expanded plastic materials

DE DIVULGATION L'installation conforme à l'invention pour la fabrication de particules de matières plastiques préexpansées comprend une cavité résonnante associée à une source d'énergie électromagnétique hyperfréquence, un circulateur à ferrites, un guide d'ondes, une vis d'Archiméde d'introduction de la matière plastique à préexpanser, une pompe doseuse de liquid polaire et un dispositif d'extraction des particules préexpansées. Les particules de matières plastiques contenant un agent de gonflement, mélangées avec un liquide polaire, sont introduites en continu dans la cavité résonnante où le liquide polaire est vaporisé sur les particules, provoquant leur expansion, leur séchage étant réalisé par introduction d'air chaud pulsé. Le procédé et l'installation conformes à l'invention, se distinguent de l'Art antérieur en ce qu'ils permettent d'obtenir des particules de matières plastiques préexpansées totalement exemptes d'eau, séchées au cours même de l'operation de préexpansion et suppriment ainsi la nécessité d'un processus de séchage consécutif à l'opération de préexpansion. Le procédé et l'installation conformes à l'invention permettent de réduire la durée du traitement et son prix de revient, et de réaliser le traitement de préexpansion en continu, et permettent en outre, une réduction considérable du temps de murissement des particules expansées, avant l'opération de moulage, et l'obtention d'objets en matières plastiques expansées d'une finition parfaite.

Non-clumping foamable thermoplastic polymer granules and method of making

Method and apparatus for producing beads from expanded or foamed thermoplastic material

Thermoplastic granule, method of producing the same and foamed molded body produced by such granules

A thermoplastic plastic granule having an expansion agent uniformly distributed within a plastic polymer-matrix and, containing additionally a cell-forming agent in a finely and uniformly distributed manner. Such thermoplastic granules are used for producing foamed molded bodies in a mold.

FOERFARANDE FOER STYRNING AV PAERLSTORLEKEN VID FRAMSTAELLNING AV EXPANDERBARA STYRENPOLYMERISAT GENOM SUSPENSIONSPOLYMERISATION.

Process for the preparation of expandable styrene polymers containing graphite particles

METHOD FOR PRODUCING FOAMED POLYPROPYLENE RESIN PARTICLES.

Patent NO135308L