Treating Polymer Derived From A Monomer Containing Only Carbon, Hydrogen, And Halogen Or Only Carbon And Halogen; Or Treating A Polymer Which Has Been Derived From At Least One Hydrocarbon And Which Has Been Subsequently Halogenated Patents (Class 521/46)
  • Patent number: 6306222
    Abstract: A process for cleaning plastic materials is disclosed, in which foreign materials adhered on and internally intruded into the plastic materials are cleaned to recycle the plastic materials. The process for cleaning plastics to recycle them according to the present invention includes the following steps. (1) A first cleaning is carried out on roughly crushed plastics of a size of 2-3 cm by using a solvent within a dumbler. (2) The solvent is discharged out of the dumbler after the first cleaning. (3) A second cleaning is carried out on the plastics by using a solvent within the dumbler after the first cleaning. (4) The solvent is discharged out of the dumbler after the second cleaning. (5) The plastics are dried after the second cleaning by injecting a heated nitrogen gas into the dumbler. (6) The nitrogen gas is discharged out of the dumbler under a reduced pressure, whereby contamination materials adhered on surfaces and internally intruded are cleaned.
    Type: Grant
    Filed: May 30, 2000
    Date of Patent: October 23, 2001
    Assignee: LG-Caltex Oil Corporation
    Inventors: In-Bok Kim, Sung-In Hong, Ik-Soo Kim, Joong-Seok Noh
  • Patent number: 6274637
    Abstract: The invention comprises a process for the recycling and production of plastics, plastics mixtures and plastics materials, using new, reprocessed or used plastics and plastics mixtures or sorted and unsorted plastics wastes, in which a) a carrier material A, which comprises a newly produced plastics material or plastics waste material containing a uniform type-pure plastic or plastics of various types, a material of any or unknown composition X and an additional component Z selected from fatty acids, mixtures containing fatty acid of natural or synthetic origin, fatty acid derivatives which release fatty acid under the process conditions and fatty alcohols are mixed together, A and X together containing, relative to the volume, at least a quantity of plastics such that the non-plastics components are incorporated therein while a homogeneous or partially homogeneous composition is still forming, b) this mixture is conveyed through a conveying device with constant mechanical mixing, kneading or compression, and
    Type: Grant
    Filed: July 29, 1999
    Date of Patent: August 14, 2001
    Assignee: Finacor Anstalt
    Inventor: Günter Schallenberg
  • Patent number: 6174928
    Abstract: A fluorinated oligomer having COOH groups at both end and a &rgr;50° value of 1,000 to 10,000 is produced by swelling a fluorine rubber crosslinking product in an organic solvent, followed by decomposition in the presence of a base and a peroxide. The obtained fluorinated oligomer is soluble in solvent and thus easy to separate from fillers, etc., and can be effectively used as a chain-elongating agent for epoxy resin, isocyanate resin, oxazoline resin, etc.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: January 16, 2001
    Assignee: Nippon Mektron, Limited
    Inventors: Fumiyo Mizuide, Haruyoshi Tatsu, Sergey Vasilievich Sokolov, Michail Vasiliyevich Zhuravlev, Igor Vladimirovich Kokotin, Olga Viktorinovna Blagodatova
  • Patent number: 6160031
    Abstract: A process for decomposing a polymer which is capable of undergoing thermal depolymerization to its monomer or monomers, such as for example poly(methylmethacrylate), and for the recovery of at least one of the monomers, includes the steps of subjecting the polymer in solid, gel, partially molten or molten form to microwave heating for a time and at a temperature sufficient to decompose the polymer to produce the monomer or monomers in gaseous, liquid or solid form, without substantial decomposition of the monomer or monomers, and recovering at least one of the monomer or monomers. The monomer or monomers may then be reused for plymerisation.
    Type: Grant
    Filed: May 19, 1999
    Date of Patent: December 12, 2000
    Assignee: AECI Limited
    Inventors: Ian Douglas Poree, Karol Paula Cameron, Janine Alison Bloem, Fritz Dieter Schlosser, Alison McGowan
  • Patent number: 6114401
    Abstract: A plastic article or plastic container reclamation process if provided in which plastic containers are divided into relatively large pieces, then washed, agitated and separated using an aqueous solvent to remove residual materials. The residual materials such as motor oil are reclaimed for reuse and the aqueous solvent is regenerated for reuse in the process. Residual materials such as dirt, labels and adhesives from the plastic containers is recovered for recycling or passed to waste for disposal or reuse.
    Type: Grant
    Filed: March 21, 1994
    Date of Patent: September 5, 2000
    Inventor: Billie Odell Doonan
  • Patent number: 6087406
    Abstract: Compositions and techniques useful to effectively recycle crosslinked (i.e., vulcanized or cured) fluoroelastomers are disclosed. The invention utilizes an additive system that includes a cure-enhancing additive, a crosslinking agent, and an accelerator.
    Type: Grant
    Filed: May 12, 1997
    Date of Patent: July 11, 2000
    Assignee: Dyneon LLC
    Inventors: Allan T. Worm, Erik D. Hare, Paul N. Nelson
  • Patent number: 6084003
    Abstract: Paint sludge is mixed with a polyether or polyester polyol. Optionally, lignin in the range of 0.25 to 70% by weight may be mixed with polyol. The paint sludge-polyol mixture is mixed with an isocyanate for curing the material into a mass. Alternatively, the lignin-polyol-paint sludge mixture is mixed with an isocyanate for curing the material into a mass. The lignin improves the flame resistance and moisture resistance of the mass. A catalyst may be added to the mixture to improve the rate of reaction.
    Type: Grant
    Filed: April 5, 1999
    Date of Patent: July 4, 2000
    Inventor: Kenneth R. Kurple
  • Patent number: 5895790
    Abstract: The present invention economically recovers wide range polymer blends and waste thermoset material. A first method of thermosetting a wide range polymer blend forms a homogenous and adaptable first method material. This material has a melt index of zero and a relatively predictable density. Very high levels of fibrous non-polymers may be added to the first method material.
    Type: Grant
    Filed: December 14, 1995
    Date of Patent: April 20, 1999
    Inventor: Elmer Good
  • Patent number: 5824745
    Abstract: Post consumer recyclable plastics are combined with a ethylene-octene copolymer and a polyamide to prepare a resin composition that can be used in conventional molding processes to fabricate new and useful plastic articles of manufacture.
    Type: Grant
    Filed: February 28, 1997
    Date of Patent: October 20, 1998
    Inventor: William F. Brown
  • Patent number: 5824709
    Abstract: A waste plastic containing a polymer such as polystyrene polypropylene or ABS resin is dissolved in a solvent to form a solution of the waste plastic at an elevated temperature. The solution is filtered to remove labels or other adhered foreign debris. The filtrate is heated to a temperature of 200.degree.-300.degree. C. under a pressure of 1-75 torrs to remove the solvent by evaporation, and the resulting plastic melt is extruded into pellet whereby the waste plastic is recovered. On the other hand, the solvent separated by the vacuum-evaporation is condensed by a water-, brine- and/or refrigerant-cooled condensers, refined by a vacuum-evaporated and recycled to use it as a solvent for the incoming subsequent waste plastic. The pelleted styrene recycle product is free of debris such as labels and accordingly has a good color. Moreover, this recycle product has a good transparency when the waste plastic is transparent.
    Type: Grant
    Filed: July 2, 1996
    Date of Patent: October 20, 1998
    Inventor: Motoshi Suka
  • Patent number: 5770633
    Abstract: Filler-containing, cross-linked, vulcanized fluorine rubber waste is regenerated by treatment with at least one of CH.sub.3 SO.sub.3 H, ClSO.sub.3 H, CF.sub.3 SO.sub.3 H and fuming sulfuric acid, followed by dissoluting into a solvent and separating solvent-insoluble filler therefrom, whereby revulcanizable fluorine rubber is recovered from the fluorine rubber waste, almost irrespective of types of cross-linking systems used for formation of cross-linked, vulcanized fluorine rubber.
    Type: Grant
    Filed: July 17, 1996
    Date of Patent: June 23, 1998
    Assignee: Nippon Mektron, Limited
    Inventors: Akihiro Naraki, Fumiyo Mizuide, Haruyoshi Tatsu
  • Patent number: 5651994
    Abstract: An elastic paving material includes a mixture of 90-50% by weight of fibrous rubber chips each having a length of 3-30 mm and a diameter of 0.3-3 mm, and 10-50% by weight of crushed pieces of golf balls having a particle size of 3-50 mesh. A curable liquid binder is added so as to bond the fibrous rubber chips and the crushed pieces of golf balls. Another elastic paving material includes only pieces of golf balls having a particle size of 3-50 mesh, and a curable liquid binder is added thereto so as to bond the pieces of golf balls. The crushed pieces of golf balls have a color different from that of the fibrous rubber chips, consist of particles having various colors, or are colored in advance.
    Type: Grant
    Filed: July 24, 1996
    Date of Patent: July 29, 1997
    Assignee: Bridgestone Sports Co., Ltd.
    Inventors: Yoshimichi Hara, Masayuki Otake, Takayuki Niikura
  • Patent number: 5554657
    Abstract: The invention described herein provides a process for recycling a mixed polymer recycle stream containing polyester polymers, particularly polyethylene terephthalate (PET) typically in the form of carbonated soft drink or other containers. This novel process includes the steps of: (1) contacting the mixed polymer recycle stream with a solvent which selectively dissolves the PET. (2) separating the selective solvent containing PET from the residual mixed polymer, (3) cooling the selective solvent to precipitate the PET, and (4) removing the selective solvent from the precipitated PET. It is preferable that the mixed polymer recycle stream be prepared for recycling by conventional steps, such as water washing. In a preferred embodiment, the mixed polymer recycle stream is chemically washed subsequent to water washing and prior to contact with the selective solvent. The PET recovered is preferably combined with "virgin" PET and further processed to increase its molecular weight.
    Type: Grant
    Filed: May 8, 1995
    Date of Patent: September 10, 1996
    Assignee: Shell Oil Company
    Inventors: Thomas F. Brownscombe, Howard L. Fong, Zaida Diaz, Hoe H. Chuah, Raymond L. June, Kevin L. Rollick, Thomas C. Semple, Mark R. Tompkin
  • Patent number: 5548028
    Abstract: Blends of previously-vulcanized fluoroelastomer with fluorine-free elastomer can be cured to have unexpectedly excellent physical properties.
    Type: Grant
    Filed: February 24, 1995
    Date of Patent: August 20, 1996
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: David L. Tabb
  • Patent number: 5475036
    Abstract: A process for reusing a plastic article having a plastic body and a coating layer is discloses which includes the following steps: peeling the coating layer, formed on the plastic body, away from the plastic body by using a high pressure water jet stream; and pulverizing the plastic body for reuse. Hot water may be also used. Instead of the water, it is possible to use high pressure steam.
    Type: Grant
    Filed: January 25, 1993
    Date of Patent: December 12, 1995
    Assignees: The Japan Steel Works, Ltd., Mitsui Toatsu Chemicals, Inc.
    Inventors: Hiroshi Hosoyama, Michiaki Yamamoto, Keigo Suehiro
  • Patent number: 5464877
    Abstract: A method for recovering a synthetic waste material contaminated with other materials, particularly waste optical disks, wherein the loose, uncrushed waste is chemically treated by impregnating said other materials with a chemical solution which attacks these materials but is substantially neutral for the synthetic material, and mechanically treated by tumbling said waste in a sealed rotary drum to dislodge the contaminated and chemically attacked materials from said synthetic material.
    Type: Grant
    Filed: March 24, 1994
    Date of Patent: November 7, 1995
    Assignee: Helverep S.A.
    Inventor: Francois-Marie Franci
  • Patent number: 5438078
    Abstract: The present invention is a method for depolymerizing organic vulcanized rubber which contains at least one organic component. In broadest terms, the method of the present invention comprises the steps of: (a) obtaining a portion of organic vulcanized rubber to be recycled; (b) treating the portion of rubber with an effective amount of:(1) a solution of at least one organic hypochlorite; and(2) at least one organic solvent; for sufficient time and at sufficient temperature whereby substantially all of the portion of the rubber is degraded to an extent so as to be dispersed in the organic solvent, whereby the organic component(s) is/are extracted therefrom.The organic vulcanized rubber (such as rubber from used tires and/or other waste sources) may be from a single source or from various sources, and those from various sources may even be comingled for treatment by the present method.
    Type: Grant
    Filed: January 18, 1994
    Date of Patent: August 1, 1995
    Assignee: Ohio University
    Inventors: Jared A. Butcher, Jr., Huw Kidwell
  • Patent number: 5385950
    Abstract: A process for the separation of different polymers, by subjecting a molten polymer mixture containing two or more polymers to a gravity field greater than the Earth's gravity field. The process is useful in the recovery of scrap or waste polymers.
    Type: Grant
    Filed: May 27, 1993
    Date of Patent: January 31, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Walter Mahler
  • Patent number: 5366998
    Abstract: A novel composition for use in reducing and recovering metals, such as silver, and for use in stripping adhesive polymer layers from various polymer bases, such as polyester, and processes for using same are provided. The composition and variations thereof can be useful in separating an adhesive polymeric layer from the film for recovery of either. The composition comprises a reducing sugar/alkaline solution that is particularly useful for recovering silver from polyester photographic film where a silver halide light-sensitive emulsion layer is adhered to the polyester film by a polymeric adhesive resin, such as resins containing copolymers of polyvinylidene chloride and polyvinyl chloride. Processes for separation and recovery are also disclosed and claimed.
    Type: Grant
    Filed: March 22, 1993
    Date of Patent: November 22, 1994
    Assignee: Partek, Inc.
    Inventor: John A. Schwartz, Jr.
  • Patent number: 5286424
    Abstract: Recycling polyolefin material, e.g. biaxially oriented polypropylene film, coated with a chlorine-containing polymer, such as polyvinylidene chloride homopolymer and/or copolymer, and having a primer therebetween. First, a caustic solution is formulated containing from about 0.1 wt. % to about 50 wt. % caustic, and from about 0.05 wt. % to about 1.0 wt. % of a wetting agent. The formulated caustic solution is heated to a temperature from about 25.degree. C. to about 140.degree. C. The polyolefin material is soaked in the heated caustic solution until the material is separable from the chlorine-containing polymer. After separating the polyolefin material from the chlorine-containing polymer, the material is reprocessed into desired product by extrusion, molding or other product forming process.
    Type: Grant
    Filed: November 9, 1992
    Date of Patent: February 15, 1994
    Assignee: Mobil Oil Corporation
    Inventors: Tien-Kuei Su, Kenneth L. Lilly, Jr.
  • Patent number: 5272186
    Abstract: A process is disclosed for the concentration of aqueous fluoropolymer dispersion. Polyacrylic acid (or its salts) or an acrylic polymer of high acid content (or its salts) of average molecular weight between 50,000 and 500,000 is used as a concentrating agent and is added to the fluoropolymer dispersion.
    Type: Grant
    Filed: May 1, 1992
    Date of Patent: December 21, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Clay W. Jones
  • Patent number: 5232954
    Abstract: This invention relates to a process for recovering an ester-soluble thermoplastic resin comprising the steps of (1) crushing a shaped thermoplastic resin, (2) contacting the crushed thermoplastic resin with an ester to form a mixture, and (3) recovering the thermoplastic resin from the mixture by removing the ester or precipitating the thermoplastic resin. This invention also relates to a process for removing ester-insoluble impurities from the thermoplastic resin. The process uses non-halogenated and hydrocarbon free solvents to recover thermoplastic resins. This invention provides a means to recover shaped thermoplastic resin without adversely affecting the thermoplastic resin, such as its molecular weight.
    Type: Grant
    Filed: May 12, 1992
    Date of Patent: August 3, 1993
    Inventor: Donald F. Peters
  • Patent number: 5198471
    Abstract: A method for separating polymers from a physically commingled solid mixture containing a plurality of polymers comprises dissolving a first one of the polymers in a solvent at a first lower temperature to form a first preferably single phase solution and a remaining solid component. The solid component contains additional polymers which are not soluable to the solvent at the first temperature but which may be soluble at higher temperatures. The method includes subsequently heating the solvent to dissolve additional polymer from the solid component to form subsequent solutions. The polymers are then separated from their respective solution either using flash evaporation techniques when more than one polymer has been dissolved at a single temperature, or conventional techniques for extracting a polymer from a solvent in a solution.
    Type: Grant
    Filed: September 11, 1989
    Date of Patent: March 30, 1993
    Assignee: Rensselaer Polytechnic Institute
    Inventors: E. Bruce Nauman, Jerry C. Lynch
  • Patent number: 5162383
    Abstract: Pure polymer, such as polyester used in photographic film and in plastic walls of drink bottles or polycarbonate used in high-quality plastic beverage bottles, is separated from thin saran, metal, and other coating layers of a multi-layer film or sheet when the film sheet is wet, as from silver recovery and like processes. The coating layer is typically 1/2% or less of the total sheet or film thickness. The abrasion process in one form comprises rotating and mixing a volume of wet plastic chips of said film or sheet with about three to five volumes of hot (160 to 300 degrees F) small, hard abrasive particles such as quartzite aggregate, glass cullet, or the like, for a time sufficient to dry the chips and also to abrade the thin coating layer from the film or sheet. The abrasive particles and the coating dust are separated from the pure polymer by screens or air classifiers. The resulting polymer chips are clean and dry and are immediately available for pelletizing and reuse.
    Type: Grant
    Filed: August 21, 1991
    Date of Patent: November 10, 1992
    Inventor: James D. Schoenhard
  • Patent number: 5061735
    Abstract: Thermoplastic materials are separated and recovered, according to the present invention, utilizing a process wherein a mixture of the thermoplastic material to be recovered and one or more contaminants are simultaneously heated and agitated. The mixture is heated to the temperature at which the thermoplastic will adhere to itself, but at which the contaminant has not become tacky. Impacting thermoplastic particles agglomerate, while the contaminant particles do not adhere to other contaminant particles or to the thermoplastic particles. The resulting mixture is passed through a series of screens of increasing mesh size to separate the larger thermoplastic particles from the smaller contaminant particles.
    Type: Grant
    Filed: August 15, 1990
    Date of Patent: October 29, 1991
    Assignee: Plastic Recovery Systems, Inc.
    Inventor: Michael P. Zielinski
  • Patent number: 5023317
    Abstract: The invention is a chemical process for complete destruction and safe disposition of hazardous organic chemicals carbonaceous chemicals. The invention also comprises the process for production of an inert polymer formed essentially of Carbon and Sulfur, and also comprises the new inert polymer, itself and articles made of the new polymer. This new polymer has many of the properties of refractory materials and is an inert non-inflammable cross-linked polymer that is relatively insoluble in all generally known solvents. In the process of the invention, a carbonaceous chemical and Sulfur is heated, in an atmosphere of Nitrogen at 500.degree. to 1500.degree. C. Waste gases including sulfur and sulfides are condensed, scrubbed and the sulfur recycled. The solids residue when analyzed by a mass spectrometer contains less than one (1) part per million (1 ppm) of unreacted organic chemical.
    Type: Grant
    Filed: March 21, 1990
    Date of Patent: June 11, 1991
    Assignee: Sultech, Inc.
    Inventor: Harold W. Adams
  • Patent number: 4921936
    Abstract: The invention is a chemical process for complete destruction and safe disposition of hazardous organic carbonaceous chemicals. The invention also comprises the process for production of an inert polymer formed essentially of Carbon and Sulfur, and also comprises the new inert polymer, itself and articles made of the new polymer. This new polymer has many of the properties of refractory materials and is an inert non-inflammable cross-linked polymer that is relatively insoluble in all generally known solvents. In the process of the invention, a carbonaceous chemical and Sulfur is heated, in an atmosphere of Nitrogen at 500.degree. to 1500.degree. C. Waste gases including sulfur and sulfides are condensed, scrubbed and the sulfur recycled. The solids residue when analyzed by a mass spectrometer contains less than one (1) part per million (1 ppm) of unreacted organic chemical.
    Type: Grant
    Filed: April 1, 1986
    Date of Patent: May 1, 1990
    Assignee: Sultech, Inc.
    Inventor: Harold W. Adams
  • Patent number: 4870110
    Abstract: Polyethylene terephthalate scrap material containing on its surface a chlorine-containing polymer such as, for example, polyvinylidene chloride or polyvinyl chloride, can be recovered and reused by melt-blending it with a polymer from a defined class of ethylene copolymers containing an epoxy group, and melt processing the blend in the same manner as virgin polyethylene terephthalate. The recovered and reprocessed polymer material has good physical properties and barrier properties.
    Type: Grant
    Filed: January 26, 1989
    Date of Patent: September 26, 1989
    Assignee: E. I. DuPont de Nemours and Company
    Inventors: Vinodkumar Mehra, Pallatheri M. Subramanian
  • Patent number: 4824512
    Abstract: Rubber based adhesives containing liquid stereospecific polybutadiene rubber, one or more hardeners or hardener systems, fillers and optionally primers, which contain one or more chemically irreversibly depolymerized solid rubbers of natural or synthetic origin in quantities of from 1.5 to 5% by weight, based on the sum of the constituents, to a process for the production of these low-viscosity rubber-based adhesives by chemically irreversible depolymerization of one or more solid rubbers of natural or synthetic origin, and to the use of these low-viscosity rubber-based adhesives in the bonding of metal components in automotive manufacturing.
    Type: Grant
    Filed: July 24, 1987
    Date of Patent: April 25, 1989
    Assignee: Henkel Kommanditgesellschaft auf Aktien
    Inventor: Hans-Peter Kohlstadt
  • Patent number: 4799954
    Abstract: A process for the recovery of silver from exposed or unexposed photographic film using a caustic alkali solution at elevated temperatures with high shear.
    Type: Grant
    Filed: March 8, 1988
    Date of Patent: January 24, 1989
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Jerome Hochberg
  • Patent number: 4777192
    Abstract: A method and apparatus for radiation degradation processing of polytetrafluoroethylene makes use of a simultaneous irradiation, agitation and cooling. The apparatus is designed to make efficient use of radiation in the processing.
    Type: Grant
    Filed: July 22, 1983
    Date of Patent: October 11, 1988
    Assignee: Shamrock Chemicals Corporation
    Inventors: William B. Neuberg, Robert Luniewski
  • Patent number: 4643861
    Abstract: Disclosed herein is a process for treating scrap thermoplastic film which has been treated with a saran coating. When the scrap film is cut into a convenient size, it is densified in the presence of a treatment medium which comprises a mixture of lime and an alkyl carboxylate and molded into pellet form. These pellets may then be employed in conventional extrusion and molding equipment without any degradation of the equipment which was normally seen when untreated saran-coated, scrap films were attempted to be molded or extruded.
    Type: Grant
    Filed: July 2, 1985
    Date of Patent: February 17, 1987
    Inventor: Joseph F. Hager
  • Patent number: 4614752
    Abstract: A process and apparatus for removing the non-metallic components from composite bodies of metal and rubber and/or plastic, which occur as waste. The composite bodies are heated in a preheating zone and then dipped into a heated solvent or exposed to the vapors of said solvent.
    Type: Grant
    Filed: June 19, 1985
    Date of Patent: September 30, 1986
    Assignee: Fuchs Recycling GmbH & Co.
    Inventors: Gerhard Fuchs, Roland R. Hertenstein, Hans G. Quick
  • Patent number: 4612057
    Abstract: A method for the recovery of silver from photographic film having a polyester base and a macromolecular organic polymer coating to which is adhered a light sensitive silver emulsion layer. The process includes mixing small film pieces in a hot aqueous liquid having a solids concentration level of at least 25 percent by volume. The mixture is subjected to conditions of high shear to remove the silver emulsion. The liquid containing the silver emulsion is then separated from the film pieces and the silver is recovered from the liquid.
    Type: Grant
    Filed: January 22, 1985
    Date of Patent: September 16, 1986
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Kenneth R. Buser, Thomas A. Rettig
  • Patent number: 4602046
    Abstract: A method for the recovery of plastic material such as polyester from scrap material such as photographic film having a polyester base and at least one layer of a macromolecular organic polymer. The process includes mixing small pieces of the scrap material in a solution having a scrap solids concentration level of at least 25 percent by volume. The mixture is subjected to conditions of high shear to remove and comminute the polymer layer to particles of a maximum size particle dimension substantially smaller than the minimum size in the longest dimension of the scrap pieces. The polymer particles are then separated from the remaining pure polyester.
    Type: Grant
    Filed: January 22, 1985
    Date of Patent: July 22, 1986
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Kenneth R. Buser, Thomas A. Rettig
  • Patent number: 4585801
    Abstract: Used or contaminated pieces of fluoropolymer membrane or sheet materials are salvaged for re-use by particulating the materials into powders, granules, or fibers, or otherwise reforming it, treating the particulated material, as desired, to cleanse or modify the material, and utilizing the material in subsequent applications.
    Type: Grant
    Filed: March 29, 1982
    Date of Patent: April 29, 1986
    Assignee: The Dow Chemical Company
    Inventors: Harry S. Burney, Jr., Donald W. Calvin
  • Patent number: 4517312
    Abstract: A process for regenerating a resin, comprises the steps of dissolving a waste resin in an organic solvent to provide a resin solution, mixing the resin solution with a liquid of normal temperature, the liquid being immiscible with the solvent, scarcely dissolving the resin, and having a specific gravity smaller than that of the solvent and larger than that of the resin, thereby separating the resin from a mixture of the resin solution and the liquid, and recovering the resin. The liquid may have a temperature higher than the boiling point of the solvent. In this case, the solvent evaporation takes place together with the resin separation. The evaporated solvent is cooled later for recovery of the solvent.
    Type: Grant
    Filed: December 19, 1983
    Date of Patent: May 14, 1985
    Assignee: Toyo Rubber Chemical Industry Co., Ltd.
    Inventors: Sadao Kumasaka, Satomi Tada, Shigeo Horikoshi, Tamaki Kamanaka, Hiroshi Taniguchi