Particle Which Is Expandible, Process Of Preparing An Expandible Particle, Or Process Of Expanding A Particle To Form A Cellular Product Patents (Class 521/56)
  • Patent number: 4596833
    Abstract: Substantially non-crosslinked polypropylene foamed particles having a bulk density of from 8 to 100 g/l and a particle diameter of from 1 to 5 mm and containing an organic sodium phosphate represented by the formula: ##STR1##
    Type: Grant
    Filed: October 22, 1985
    Date of Patent: June 24, 1986
    Assignee: Mitsubishi Yuka Badische Co., Ltd.
    Inventors: Hiroshi Endo, Toshio Yagi
  • Patent number: 4588751
    Abstract: Expandable styrene polymer particles which have anti-stratification and anti-lumping properties during expansion are produced by dry blending styrene polymer particles in the presence of 0.01-0.04 parts of alkyl and alkylaryl ethers of polyethoxyethanol mono- and diesters of phosphoric acid per 100 parts of polymer particles. The esters may be added as sole anti-stratification or anti-lumping agent or in addition to known anti-lumping agents.
    Type: Grant
    Filed: October 25, 1985
    Date of Patent: May 13, 1986
    Assignee: Atlantic Richfield Company
    Inventor: Alvin R. Ingram
  • Patent number: 4587270
    Abstract: Preliminarily foamed particles of a non-crosslinked polypropylene resin based on an alpha-olefin/propylene random copolymer having an amount of the heat of crystallization in the range of 5 to 15 cal/g, said preliminarily foamed particles having such a crystal structure that when a DSC curve is drawn by means of a differential scanning calorimeter, by heating 1 to 3 mg of the preliminarily foamed particles to 220.degree. C. at a rate of 10.degree. C./min., a high temperature peak is observed at a higher temperature than the temperature of the peak inherent to the base resin.
    Type: Grant
    Filed: November 21, 1984
    Date of Patent: May 6, 1986
    Assignee: Japan Styrene Paper Corporation
    Inventors: Hideki Kuwabara, Yoshimi Sudo
  • Patent number: 4582859
    Abstract: An improved process for the manufacture of crosslinked copolymer particles from seed particles by imbibing a monomer therein and polymerizing the same under controlled suspension conditions wherein said improvement comprises expanding the seed in staged or sequential steps of feeding lower levels of crosslinking monomers in the early stages and preferably higher levels of crosslinking monomers at later stages of polymerization.
    Type: Grant
    Filed: December 2, 1983
    Date of Patent: April 15, 1986
    Assignee: Rohm and Haas Company
    Inventors: George M. Lein, Jr., Thomas J. Howell, James H. Barrett
  • Patent number: 4582860
    Abstract: Carriers for immobilizing enzymes may be prepared by suspension copolymerizing an oxirane-group-bearing, monovinyl monomer and a major amount of a trivinyl crosslinking monomer having a hydrophilic character, in the presence of a phase separator which does not react with the oxirane group. The resulting carriers, in bead form, have high porosity, high surface area, and pores of diameter sufficient for ready penetration by enzymes and substrates.
    Type: Grant
    Filed: December 15, 1983
    Date of Patent: April 15, 1986
    Assignee: Rohm and Haas Company
    Inventors: Michael P. Bigwood, John O. Naples
  • Patent number: 4579873
    Abstract: A foam structure having a density of less than about 20 lbs/ft.sup.3. The method of forming the same comprising forming a homogeneous melt blend under pressure of a polymer member selected from the group consisting of polyetherimide resin particles, polycarbonate resin particles, a polymer blend of polyphenylene oxide and polystyrene in particle form imbibed with a blowing agent, followed by extrusion of the same into a lower pressure atmosphere. A composition comprising said particles imbided with methylene chloride, chloroform, 1,1,2-trichloroethane or mixtures thereof. A method of thermoforming said foam in sheet form.
    Type: Grant
    Filed: July 19, 1985
    Date of Patent: April 1, 1986
    Assignee: Mobil Oil Corporation
    Inventors: Charles M. Krutchen, Wen-Pao Wu
  • Patent number: 4579710
    Abstract: A foam structure having a density of less than about 20 lbs/ft.sup.3. The method of forming the same comprising forming a homogeneous melt blend under pressure of a polymer member selected from the group consisting of polyetherimide resin particles, polycarbonate resin particles, a polymer blend of polyphenylene oxide and polystyrene in particle form imbibed with a blowing agent, followed by extrusion of the same into a lower pressure atmosphere. A composition comprising said particles imbibed with methylene chloride, chloroform, 1,1,2-trichloroethane or mixtures thereof. A method of thermoforming said foam in sheet form.
    Type: Grant
    Filed: July 19, 1985
    Date of Patent: April 1, 1986
    Assignee: Mobil Oil Corporation
    Inventors: Charles M. Krutchen, Wen-Pao Wu
  • Patent number: 4579872
    Abstract: Expandable beads and the like of thermoplastic organic polymer material, advantageously lightly-crosslinked in preparation, which are imbibed with halocarbon and/or light hydrocarbon (including mixed) blowing agents are advantageously tempered to provide excellent quality, uniformly fine-celled expanded cellular products therefrom by a quick quench from imbibition temperature to below 10 or so .degree. C. within one minute.
    Type: Grant
    Filed: May 6, 1985
    Date of Patent: April 1, 1986
    Assignee: The Dow Chemical Company
    Inventor: David R. Johnson
  • Patent number: 4579878
    Abstract: A foam structure having a density of less than about 20 lbs/ft.sup.3. The method of forming the same comprising forming a homogeneous melt blend under pressure of a polymer member selected from the group consisting of polyetherimide resin particles, polycarbonate resin particles, a polymer blend of polyphenylene oxide and polystyrene in particle form imbibed with a blowing agent, followed by extrusion of the same into a lower pressure atmosphere. A composition comprising said particles imbibed with methylene chloride, chloroform, 1,1,2-trichloroethane or mixtures thereof. A method of thermoforming said foam in sheet form.
    Type: Grant
    Filed: November 9, 1984
    Date of Patent: April 1, 1986
    Assignee: Mobil Oil Company
    Inventors: Charles M. Krutchen, Wen-Pao Wu
  • Patent number: 4576973
    Abstract: The crosslinked, porous copolymer in the form of beads and containing 50 to 99.9% by weight of recurring units of a heterocyclic 5-membered ring compound which contains a polymerizable olefinic group and which has at least one protonizable nitrogen atom in the ring, 0.1 to 50% by weight of units of a crosslinking agent, 0 to 25% by weight of units of a polymerizable organoboron or organosilicon compound and, relative to 100% by weight of the sum of the abovementioned units, 5 to 350% by weight of units of an N-vinylamide of the general formula I CH.sub.2 .dbd.CH--N(R.sup.1)--C(R.sup.2).dbd.O wherein R.sup.1 denotes hydrogen, methyl or ethyl and R.sup.2 denotes hydrogen or C.sub.1 -C.sub.3 -alkyl, or several such N-vinylamides and 0 to 40% by weight of units of another polymerizable compound or several such compounds, is prepared by inverted suspension polymerization and is used, for example, as a sorbent for acid substances from solutions thereof, preferably aqueous solutions.
    Type: Grant
    Filed: June 22, 1984
    Date of Patent: March 18, 1986
    Assignee: Cassella Aktiengesellschaft
    Inventors: Karl-Heinz Keil, Fritz Engelhardt, Ulrich Greiner, Klaus Kuhlein, Reinhold Keller, Merten Schlingmann, Gerhard Hess
  • Patent number: 4569949
    Abstract: Expandable styrene acrylonitrile polymer particles are provided which give good resiliency over an extended period of time.
    Type: Grant
    Filed: June 17, 1985
    Date of Patent: February 11, 1986
    Assignee: The Dow Chemical Company
    Inventor: John W. Brenner
  • Patent number: 4568706
    Abstract: The invention relates to bead polymers based on monomers of the formula ##STR1## in which X is hydrogen or methyl, R denotes an aliphatic hydrocarbon radical having 1 to 12 carbon atoms, and Y denotes OH or NH.sub.2, which have been prepared using a special dispersion stabilizer. They are particularly distinguished by high porosity and are very suitable as carrier materials for biologically active substances.
    Type: Grant
    Filed: May 25, 1984
    Date of Patent: February 4, 1986
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Siegfried Noetzel, Otto Mauz, Klaus Sauber
  • Patent number: 4563481
    Abstract: Expandable styrene acrylonitrile polymer particles are provided which give good resiliency over an extended period of time.
    Type: Grant
    Filed: July 25, 1984
    Date of Patent: January 7, 1986
    Assignee: The Dow Chemical Company
    Inventor: John W. Brenner
  • Patent number: 4560705
    Abstract: A method of impregnating polystyrene beads with an aliphatic hydrocarbon, rendering it into expandable polystyrene. The method involves the use of an improved impregnating solution or bath. The solution includes water, an expanding agent, the polystyrene beads and soaps which act as anti-agglomeration agents. The beads are maintained in the solution for a selected time period and at a temperature and pressure suitable to permit the expanding agent to impregnate the beads. The beads are then separated from the solution and, after drying, they are ready for use, no further processing being required.
    Type: Grant
    Filed: May 2, 1985
    Date of Patent: December 24, 1985
    Assignee: Texstyrene Plastics, Inc.
    Inventor: James M. Harrison
  • Patent number: 4548956
    Abstract: An expandable polymeric styrene particle is provided from which molded foamed articles can be produced exhibiting reduced flammability characteristics. The expandable polymeric styrene particle contains a blowing agent, a minor amount of pentaerythritol tetrastearate and a minor amount of hexabromocyclododecane. The additives can be incorporated during impregnation with the blowing agent or by blending with the expandable particles after impregnation.
    Type: Grant
    Filed: March 18, 1985
    Date of Patent: October 22, 1985
    Assignee: Cosden Technology, Inc.
    Inventor: Richard A. Schwarz
  • Patent number: 4547527
    Abstract: The absorption of water by styrene/maleic anhydride copolymer particles during the impregnation of the particles in aqueous suspension is greatly reduced by the addition of salt to the impregnation system.This process produces expandable particles of non-equimolar copolymers of styrene and maleic anhydride having considerable less heterogeneity, finer cell structure, greater expandability, less heat sensitivity, less shrinkage, and lower density potential on molding.
    Type: Grant
    Filed: December 10, 1984
    Date of Patent: October 15, 1985
    Assignee: Atlantic Richfield Company
    Inventor: Alvin R. Ingram
  • Patent number: 4540718
    Abstract: 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.
    Type: Grant
    Filed: February 29, 1984
    Date of Patent: September 10, 1985
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Kenichi Senda, Masao Ando, Kyoichi Nakamura, Tatehiko Nishida
  • Patent number: 4539335
    Abstract: Expandable thermoplastic resin particles having excellent heat resistance, solvent resistance, foamability and moldability comprising a copolymer of 10 to 80% by weight of .alpha.-methylstyrene, 5 to 50% by weight of acrylonitrile and 0 to 70% by weight of at least one member selected from the group consisting of styrene, methyl methacrylate, vinyl toluene and t-butylstyrene, and an expanding agent impregnated in the copolymer, prepared easily in high conversions by an aqueous suspension polymerization using particular difunctional organic peroxides, preferably those capable of producing t-butoxy radicals, followed by impregnation of the produced polymer particles with the expanding agent.
    Type: Grant
    Filed: May 4, 1984
    Date of Patent: September 3, 1985
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Kiyoshi Mori, Masao Nakagawa
  • Patent number: 4532264
    Abstract: Excellently properties, thermoplastic compositions well adapted for conversion by conventional melt-processing extrusion and other ordinary fabrication techniques into very good quality, lightly cross-linked, thermocollapse-resistant, closed-cell plastic foam(s) and the like expanded cellular product(s) are comprised of an intimate mixture of:(A) a sparsely hydroxylated, normally-solid olefin polymer, particularly a linear alkenyl aromatic or polyolefin polymer which is frequently at least substantially a styrene polymer which is generally in copolymeric form with appropriate moieties of comonomers adapted to provide the requisite attached hydroxyl units therein and thereon; and(B) a minor proportion of an inter-reactive, cross-linking polyisocyanate constituent.
    Type: Grant
    Filed: April 27, 1984
    Date of Patent: July 30, 1985
    Assignee: The Dow Chemical Company
    Inventor: Louis C. Rubens
  • Patent number: 4525484
    Abstract: Particulate polystyrene containing blowing agent and having improved expandability is based on polystyrene having a weight-average mean molecular weight of not more than from 130,000 to 180,000 and a molecular weight distribution curve in which the high molecular weight flank drops steeply. The expandable polystyrene particles are produced by polymerizing styrene in aqueous suspension in the presence of blowing agents and of chain transfer agents or styrene oligomers.
    Type: Grant
    Filed: June 21, 1984
    Date of Patent: June 25, 1985
    Assignee: BASF Aktiengesellschaft
    Inventors: Klaus Hahn, Paul Wittmer, Isidoor De Grave, Rupert Schick, Adolf Echte
  • Patent number: 4525486
    Abstract: A process for preparing modified polyolefin particles which comprises dispersing cross-linked polyolefin particles and a polymerizable vinyl monomer capable of dissolving or swelling the cross-linked polyolefin particles in an aqueous medium, impregnating the cross-linked polyolefin particles with the vinyl monomer and polymerizing the vinyl monomer. The obtained modified polyolefin particles can provide a foamed article including uniform and fine cells and having excellent toughness, accuracy of demension, cushioning property, heat resistance and smooth and soft surface.
    Type: Grant
    Filed: October 28, 1983
    Date of Patent: June 25, 1985
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Shigeru Kobayashi, Munehiro Nakamura
  • Patent number: 4525485
    Abstract: 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.
    Type: Grant
    Filed: September 6, 1984
    Date of Patent: June 25, 1985
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Hirofumi Maeda, Kyoichi Nakamura, Hisatoshi Fukui
  • Patent number: 4524154
    Abstract: 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 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 disc
    Type: Grant
    Filed: September 6, 1984
    Date of Patent: June 18, 1985
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Hirofumi Maeda, Kyoichi Nakamura, Toshihiro Hatamoto
  • Patent number: 4522953
    Abstract: Cross-linked homogenous porous polymeric materials are prepared by polymerization of monomers as the continuous phase in a high internal phase emulsion having above a critical limit of surfactant to ensure adequate absorbtivity. The porous materials may be dried and refilled with selected liquids and act as a high capacity reservoir.
    Type: Grant
    Filed: September 24, 1984
    Date of Patent: June 11, 1985
    Assignee: Lever Brothers Company
    Inventors: Donald Barby, Zia Haq
  • Patent number: 4520136
    Abstract: An expandable polymeric styrene particle is provided from which molded foamed articles can be produced exhibiting reduced flammability characteristics. The expandable polymeric styrene particle contains a blowing agent, a minor amount of pentaerythritol tetrastearate and a minor amount of hexabromocyclododecane. The additives can be incorporated during impregnation with the blowing agent or by blending with the expandable particles after impregnation.
    Type: Grant
    Filed: September 24, 1982
    Date of Patent: May 28, 1985
    Assignee: Cosden Technology, Inc.
    Inventor: Richard A. Schwarz
  • Patent number: 4520135
    Abstract: Particulate polystyrene containing blowing agent and having improved expandability is based on polystyrene having a weight-average mean molecular weight of not more than from 130,000 to 180,000 and a molecular weight distribution curve in which the high molecular weight flank drops steeply. The expandable polystyrene particles are produced by polymerizing styrene in aqueous suspension in the presence of blowing agents and of chain transfer agents or styrene oligomers.
    Type: Grant
    Filed: September 13, 1983
    Date of Patent: May 28, 1985
    Assignee: BASF Aktiengesellschaft
    Inventors: Klaus Hahn, Paul Wittmer, Isidoor De Grave, Rupert Schick, Adolf Echte
  • Patent number: 4520071
    Abstract: A spherical porous polyimide powder which is thermally infusible and is insoluble in an organic solvent, comprising spherical porous particles of a weight average particle diameter of 1 to 20 .mu.m comprising an aromatic polyimide having an inherent viscosity measured in sulfuric acid at a concentration of 0.5 g/dl at temperature of 30.+-.0.01.degree. C. of 0.1 to 2.0, wherein a packed bulk density is 100 to 600 g/l and a specific surface area measured by a nitrogen absorption method is 1 m.sup.2 /g or more.
    Type: Grant
    Filed: June 4, 1984
    Date of Patent: May 28, 1985
    Assignee: Nitto Electric Industrial Co., Ltd.
    Inventors: Yuzuru Noda, Toshio Nakajima
  • Patent number: 4517314
    Abstract: Fine particulate expandable styrene polymers suitable for the production of molded bodies with improved minimum mold dwell times, containing 0.01 to 2.0% by weight, referred to the polystyrene or the total of the polymerized monomers, of polyoctenamer having I values from about 10 to 400 ml/g and trans octylene contents from about 20 to 90%.
    Type: Grant
    Filed: October 17, 1984
    Date of Patent: May 14, 1985
    Assignee: Chemische Werke Huls AG
    Inventors: Dirk Reese, Josef K. Rigler
  • Patent number: 4513105
    Abstract: Particulate polystyrene containing blowing agent and having improved expandability is based on polystyrene having a weight-average mean molecular weight of not more than from 130,000 to 180,000 and a molecular weight distribution curve in which the high molecular weight flank drops steeply. The expandable polystyrene particles are produced by polymerizing styrene in aqueous suspension in the presence of blowing agents and of chain transfer agents or styrene oligomers.
    Type: Grant
    Filed: June 21, 1984
    Date of Patent: April 23, 1985
    Assignee: BASF Aktiengesellschaft
    Inventors: Klaus Hahn, Paul Wittmer, Isidoor De Grave, Rupert Schick, Adolf Echte
  • Patent number: 4513106
    Abstract: A process for expanding expandable thermoplastic microspheres containing a blowing agent which will be volatilized at heating. A slurry of the unexpanded spheres is fed to a pressure zone together with steam whereby volatilization of the blowing agent occurs in the zone and the expanded microspheres are then allowed to leave the zone at a considerable pressure drop.
    Type: Grant
    Filed: November 22, 1983
    Date of Patent: April 23, 1985
    Assignee: KemaNord AB
    Inventors: Anders Edgren, Jan Soderberg, Bengt Bergstrom
  • Patent number: 4504534
    Abstract: A core material for automobile bumpers which is composed of a molded article of foamed particles of a polypropylene-type resin. The molded article has a density of 0.015 to 0.045 g/cm.sup.3 and a compression stress at 50% compression of at least 1 kg/cm.sup.2. The core material simultaneously has excellent energy absorbing property and dimensional recovery and a low density.
    Type: Grant
    Filed: June 13, 1984
    Date of Patent: March 12, 1985
    Assignees: Japan Styrene Paper Corporation, Nissan Motor Company, Limited
    Inventors: Akira Adachi, Takashi Kubota, Yukio Okada, Kenichi Miyazaki, Taro Hagiwara
  • Patent number: 4504601
    Abstract: A process for producing pre-foamed particles of a polypropylene resin which comprises expanding original pre-foamed particles of a polypropylene resin, said original pre-foamed particles having the following relation2<E.sup.1/3 .times.n.sup.1/2 <45wherein E is the expansion ratio of the original pre-foamed particles, and n is the number of cells per mm.sup.2 of the cross section of the original pre-foamed particles,by (1) imparting expanding ability to the original pre-foamed particles and then heating them with a heated gas to the heat distortion temperature of the base resin of the pre-foamed particles or a higher temperature or (2) heating the original pre-foamed particles with steam to the heat distortion temperature of the base resin of the particles or a higher temperature with or without imparting expanding ability thereto, whereby pre-foamed particles having an expansion ratio higher than the original expansion ratio E are obtained.
    Type: Grant
    Filed: September 29, 1983
    Date of Patent: March 12, 1985
    Assignee: Japan Styrene Paper Corporation
    Inventors: Hideki Kuwabara, Shohei Yoshimura, Toru Yamaguchi, Yoshimi Sudo
  • Patent number: 4497911
    Abstract: Process for the production of fine particulate, expandable styrene polymers by suspension-polymerizing styrene or possibly mixtures of styrene and other monomers having at least 50% by weight of styrene in the presence of expanding agents having low boiling points in incompletely filled reactors. The polymer beads to be charged with expanding agents are vigorously stirred during the addition of the expanding agent(s) in such a manner that these beads undergo the least possible contact in time and space with the gas phase and with each other, and so that the surface of the stirred medium retains a topology as free as possible from a funnel shape during stirring.
    Type: Grant
    Filed: July 8, 1982
    Date of Patent: February 5, 1985
    Assignee: Chemische Werke Huls AG
    Inventors: Josef K. Rigler, Karl Trukenbrod, Franz-Michael Bollenrath
  • Patent number: 4497912
    Abstract: Fine particulate expandable styrene polymers suitable for the production of molded bodies with improved minimum mold dwell times, containing 0.01 to 2.0% by weight, referred to the polystyrene or the total of the polymerized monomers, of polyoctenamer having I values from about 10 to 400 ml/g and trans octylene contents from about 20 to 90%.
    Type: Grant
    Filed: June 18, 1984
    Date of Patent: February 5, 1985
    Assignee: Chemische Werke Huls AG
    Inventors: Dirk Reese, Josef K. Rigler
  • Patent number: 4471077
    Abstract: Microporous polylactide powders having an intrinsic isotropic structure being spherical in a shape and containing interconnecting hollow spaces or openings i.e., micropores are obtained by the steps of heating a polylactide in xylene until substantially complete solution is reached; cooling the resultant clear solution; and separating off the xylene.The microporous powder form powders can have active substances such as a medicament introduced therein i.e. unto the pores and the resultant powder can be used for controllably dispensing the medicament i.e., as a prolonged release form.
    Type: Grant
    Filed: May 16, 1983
    Date of Patent: September 11, 1984
    Assignee: Akzo NV
    Inventor: Wolfgang Lange
  • Patent number: 4464489
    Abstract: Spherical porous polyimide powder having an average particle diameter of 1 to 20 .mu.m which is infusible and insoluble in organic solvents is produced by polymerizing an aromatic tetracarboxylic acid dianhydride and an aromatic polyisocyanate in an organic solvent at a temperature of 100.degree. to 200.degree. C. and in the presence of a tertiary amine catalyst to form polyimide particles in the form of slurry, filtering or centrifuging said polyimide particles, and washing the resulting polyimide particles with an organic solvent.
    Type: Grant
    Filed: December 12, 1983
    Date of Patent: August 7, 1984
    Assignee: Nitto Electric Industrial Co., Ltd.
    Inventors: Yuzuru Noda, Toshio Nakajima
  • Patent number: 4464484
    Abstract: 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.
    Type: Grant
    Filed: December 13, 1983
    Date of Patent: August 7, 1984
    Assignee: Japan Styrene Paper Corporation
    Inventors: Shohei Yoshimura, Hideki Kuwabara
  • Patent number: 4461876
    Abstract: A polymeric reagent for the isolation and protection of carbonyl compounds comprising a polymer having a functional group of the formula --ONH.sub.2 covalently attached to the polymer where the functional group is capable of reacting with a carbonyl group of a carbonyl compound when a solution containing the carbonyl compound contacts the polymeric reagent is disclosed along with methods of using this reagent.
    Type: Grant
    Filed: September 9, 1982
    Date of Patent: July 24, 1984
    Assignee: Columbia University
    Inventors: Seymour Lieberman, Veeramac V. K. Prasad, Patricia A. Warne
  • Patent number: 4461848
    Abstract: An improved process for the manufacture of vesiculated beads has been developed which can be used for the production of semi-gloss or satin finished paints. The process involves mixing an oil-phase containing a cross-linkable polyester resin in solution with a monomer co-polymerizable with the resin and an aqueous phase containing an emulsifying agent under conditions such that globules of the oil-phase are formed having a diameter of less than 1.5 microns. The emulsion containing the globules also contains a base and the amount of the emulsifying agent is from 3 to 16 grams per 100 ml of the oil-phase and the volume fraction has a value of 0.2 to 0.4 and X as defined is from 4 to 8. Preferably the beads are pigmented with titanium dioxide pigment.
    Type: Grant
    Filed: October 29, 1982
    Date of Patent: July 24, 1984
    Assignee: Tioxide Group Plc.
    Inventors: Edmund J. Lawson, Charles G. Waterfield
  • Patent number: 4459373
    Abstract: The invention relates to pre-expanded plastic beads based on poly-para-methylstyrene with the following properties:(a) the bead size lies between 0.2 and 3 cm,(b) the thermal stability, measured in accordance with DIN 53,424 is above 110.degree. C., and(c) the bulk density is below 35 g/l.The corresponding expandable plastic beads are prepared through the polymerization of para-methylstyrene in an aqueous suspension with the addition of volatile organic blowing agents during or after polymerization, whereby polymerization occurs in the presence of molecular-weight-regulating substances. Typical molecular-weight-regulating substances are organic chain transfer agents with a transfer constant K between 0.1 and 50, said agents being added in amounts ranging from 0.1 percent by weight to 1 percent by weight when a yield ranging from 20 to 95 percent is reached. Oligomers of the styrene or para-methylstyrene in quantities from 0.1 percent by weight to 10 percent by weight may also be employed.
    Type: Grant
    Filed: September 13, 1983
    Date of Patent: July 10, 1984
    Assignee: BASF Aktiengesellschaft
    Inventors: Klaus Hahn, Isidoor De Grave, Rupert Schick
  • Patent number: 4458057
    Abstract: There is disclosed a process for making vinyl polymer particles that are spherical, highly porous and of uniform size and substantially no polymer buildup on the reactor surfaces. A dispersion or emulsion is first formed with high agitation comprised of an aqueous medium containing a water-insoluble suspending or dispersing agent, the monomer or monomers to be polymerized, a monomer-soluble free radical yielding catalyst, and a surfactant or surfactant system. The dispersion is neutralized with an alkali and then polymerized with stirring to a conversion of about 10% to about 30% and then continuing the reaction to completion with increased stirring, the stirring in both instances being no greater than that used in making the dispersion or emulsion. The dispersing agent employed comprises an unneutralized crosslinked interpolymer of one or more carboxylic acid monomers with a polyunsaturated compound having a plurality of terminally unsaturated polymerizable groups.
    Type: Grant
    Filed: October 27, 1982
    Date of Patent: July 3, 1984
    Assignee: The BF Goodrich Company
    Inventor: Pijus K. Basu
  • Patent number: 4454198
    Abstract: Porous, powdery polypropylene is disclosed, obtained by providing a hot solution of polypropylene in pentaerythrol ester as solvent, slowly cooling said solution down to approximately room temperature to provide a solidified mass with or without affecting mechanical size reduction of said solidified mass, and extracting said solidified mass with an extractant in which pentaerythrol is soluble, with or without subsequently removing said solvent to a high degree.
    Type: Grant
    Filed: February 7, 1983
    Date of Patent: June 12, 1984
    Assignee: Akzo nv
    Inventors: Walter Fickel, Gerhard Ries
  • Patent number: 4448901
    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 mm.sup.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.
    Type: Grant
    Filed: May 13, 1983
    Date of Patent: May 15, 1984
    Assignee: Kanegafuchi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Kenichi Senda, Masao Ando, Kyoichi Nakamura, Kiyoshi Mori, Tatehiko Nishida
  • Patent number: 4442232
    Abstract: Expandable styrene-maleic anhydride copolymer particles which comprises a copolymer resin obtained by reaction of a styrene-maleic anhydride copolymer with a hydroxy compound and further impregnated with a volatile blowing agent.
    Type: Grant
    Filed: November 12, 1980
    Date of Patent: April 10, 1984
    Assignee: Sekisui Plastic Co., Ltd.
    Inventors: Mutsuhiko Kajimura, Tetsuji Maeda
  • Patent number: 4439547
    Abstract: Expandable vinyl aromatic polymers are produced, which exhibit anti-lumping properties and fast-cool properties upon formation of foamed articles therefrom, by polymerizing a vinyl aromatic monomer, in which is dissolved 0.5-4.0 percent, based on the monomer, of a graded diblock rubbery copolymer of 2-50 percent of polymerized vinyl aromatic monomer and 50-98 percent conjugated diene, the polymerization forming vinyl aromatic polymer containing the graded diblock rubbery copolymer, and impregnating the polymer so produced, with a blowing agent.
    Type: Grant
    Filed: May 16, 1983
    Date of Patent: March 27, 1984
    Assignee: Atlantic Richfield Company
    Inventor: Adolph V. DiGiulio
  • Patent number: 4439490
    Abstract: An improved expandable polymeric styrene particle is provided containing a blowing agent, a minor amount of pentaerythritol tetrastearate, overcoated with a minor amount of glyceryl monostearate. The improved particle results in a significantly reduced final mold cooling cycle in producing the finished molded article. Pentaerythritol tetrastearate is preferably incorporated during impregnation with the blowing agent and glyceryl monostearate overcoated by blending with the expandable particles after impregnation.
    Type: Grant
    Filed: October 24, 1983
    Date of Patent: March 27, 1984
    Assignee: Cosden Technology, Inc.
    Inventor: Richard A. Schwarz
  • Patent number: 4438222
    Abstract: This invention produces heat resistant expandable plastic particles by the method of emulsion polymerization, containing .alpha.-alkylstyrene 15-55 weight %, another polymerizable monomer 85-45 weight %, and a readily volatile blowing agent 3-15 weight % as chief ingredients, and offers the expandable plastic molded articles with high heat resistance and high dimensional stability produced by prefoaming the expandable polymerizate particles with heating at a pressure of more than 0.1 kg/cm.sup.2 G followed by heat-molding in a metallic mold.
    Type: Grant
    Filed: January 14, 1983
    Date of Patent: March 20, 1984
    Assignee: Kanegafuchi Chemical Industry Co., Ltd.
    Inventors: Masao Nakagawa, Tatehiko Nishida
  • Patent number: 4436840
    Abstract: In a process for producing pre-foamed particles of a polyolefin resin which comprises impregnating a volatile blowing agent into particles of a polyolefin resin while dispersing the resin particles and the blowing agent in a dispersing medium under heat in a closed vessel, opening one end of the vessel and releasing the resin particles and the dispersing medium simultaneously into an atmosphere kept at a lower pressure than the inside pressure of the vessel; the improvement wherein the pressure of the inside of the vessel after opening its one end is maintained at a substantially constant pressure which is at least 0.7 times the vapor pressure of the blowing agent before opening the end of the vessel.
    Type: Grant
    Filed: September 21, 1982
    Date of Patent: March 13, 1984
    Assignee: Japan Styrene Paper Corporation
    Inventors: Hiroyuki Akiyama, Sumio Shimada, Kuninori Hirosawa, Hideki Kuwabara
  • Patent number: 4435524
    Abstract: Process for making porous, substantially spherical particles having high bulk density of vinyl polymers or resins by the use of the suspension polymerization technique. In the polymerization there is employed a water-insoluble dispersant comprised of a substantially unneutralized crosslinked interpolymer of one or more carboxylic acid monomers with a polyunsaturated compound having a plurality of terminally unsaturated polymerizable groups and a surfactant system comprising at least one surfactant selected from the group consisting of a polyethylene oxide containing surfactant and a non-polyethylene oxide containing surfactant. Excellent results are obtained when both a polyethylene oxide and a non-polyethylene oxide containing surfactant are used in the process of the invention. Rapid stirring or high agitation is used while employing a monomer-soluble free radical yielding polymerization catalyst.
    Type: Grant
    Filed: November 18, 1982
    Date of Patent: March 6, 1984
    Assignee: The B. F. Goodrich Company
    Inventor: Kornelius Dinbergs
  • Patent number: RE31756
    Abstract: Methods of making modified polyimide/polyimide-amide foams and the resulting compositions. An N-substituted aliphatic imide is prepared by reacting a suitable aromatic dianhydride with a suitable oxoimine. A polyimide forming material is prepared by dissolving the N-substituted aliphatic imide in an esterifying solvent, then adding a suitable aromatic diamine. This material is dried to a powder or film. A foam is produced by heating the material to reaction temperature for a period sufficient to produce a stable foam. The material melts, then spontaneously expands into a foam which becomes self supporting and cures to a resilient flexible foam. Depending upon heating conditions, a polyimide, polyimide-amide or mixture thereof may be produced, resulting in foams having varying physical properties.
    Type: Grant
    Filed: December 27, 1983
    Date of Patent: December 4, 1984
    Inventors: John Gagliani, John V. Long