Patents Assigned to Polysar Limited
  • Patent number: 5336719
    Abstract: Tough transparent thermoplastics blends may be prepared by blending 10 to 99 weight percent of a block copolymer; 0.1 to 1 weight percent of particulate rubber having a particle size from 0.1 to 10 microns; and the balance a clear glassy polymer. These clear polymers are useful in a number of application, particularly for those applications requiring quite high toughness and transparency such as packaging, containers or protective covering.
    Type: Grant
    Filed: April 26, 1993
    Date of Patent: August 9, 1994
    Assignee: Polysar Limited
    Inventors: Ronald J. Thompson, James Lunt, John C. Lamont, John C. Kwok
  • Patent number: 5252664
    Abstract: Tough transparent thermoplastics blends may be prepared by blending 10 to 99 weight percent of a block copolymer; 0.1 to 1 weight percent of particulate rubber having a particle size from 0.1 to 10 microns; and the balance a clear glassy polymer. These clear polymers are useful in a number of applications, particularly for those applications requiring quite high toughness and transparency such as packaging, containers or protective covering.
    Type: Grant
    Filed: June 27, 1991
    Date of Patent: October 12, 1993
    Assignee: Polysar Limited
    Inventors: Ronald J. Thompson, James Lunt, John C. Lamont, John C. Kwok
  • Patent number: 5244965
    Abstract: The present invention provides a process to remove phosphine residues from a hydrogenated polymer solution.
    Type: Grant
    Filed: June 14, 1989
    Date of Patent: September 14, 1993
    Assignee: Polysar Limited
    Inventors: Akhtar Osman, William G. Bradford
  • Patent number: 5194528
    Abstract: The dimer content in alpha, beta- ethylenically unsaturated ketones may be reduced by treating the ketone with a peroxide of the formula ##STR1## wherein R.sub.4 is a C.sub.1-6 branched or straight chain alkyl radical or a C.sub.6-10 aromatic radical and n is 1 or 2. The treated ketone has a faster rate of polymerization with other ethylenically unsaturated monomers.
    Type: Grant
    Filed: June 20, 1989
    Date of Patent: March 16, 1993
    Assignee: Polysar Limited
    Inventors: Brian H. A. Smith, Melvin K. Allison
  • Patent number: 5079296
    Abstract: Tough transparent thermoplastics blends may be prepared by blending 10 to 99 weight percent of a block copolymer; 0.1 to 1 weight percent of particulate rubber having a particle size from 0.1 to 10 microns; and the balance a clear glassy polymer. These clear polymers are useful in a number of applications, particularly for those applications requiring quite high toughness and transparency such as packaging, containers or protective covering.
    Type: Grant
    Filed: July 21, 1989
    Date of Patent: January 7, 1992
    Assignee: Polysar Limited
    Inventors: Ronald J. Thompson, James Lunt, John C. Lamont, John C. Kwok
  • Patent number: 5051299
    Abstract: The present invention relates to fiber-reinforced belts, such as timing belts or conveyor belts, which are manufactured from a hydrogenated nitrile rubber having oxazoline functionality. Thus, the hydrogenated nitrile rubber contains less than 10 mole percent carbon-carbon double bond unsaturation and a functional group which may be identified using infrared spectroscopy by a characteristic peak between 1552 cm.sup.-1 and 1668 cm.sup.-1. The present belts are further characterized by having excellent adhesion between the fiber reinforcement and the oxazoline functionalized hydrogenated nitrile rubber.
    Type: Grant
    Filed: October 13, 1989
    Date of Patent: September 24, 1991
    Assignee: Polysar Limited
    Inventor: Trevor A. Brown
  • Patent number: 5045603
    Abstract: A chlorinated ethylene-alpha olefin-nonconjugated diolefin terpolymer having a chlorine content of from about 0.5 to 14 percent by weight characterized by superior viscosity stability on storage or exposure to elevated temperatures is obtained by chlorinating an ethylene-alpha olefin-nonconjugated diolefin terpolymer wherein said nonconjugated diolefin is an acyclic nonconjugated diolefin characterized in that one olefinic bond is monosubstituted and terminal and the other olefinic bond is trisubstituted. A vulcanizable rubber composition comprising said chlorinated ethylene-alpha olefin-nonconjugated diolefin terpolymer and cure active agents is also provided.
    Type: Grant
    Filed: July 19, 1990
    Date of Patent: September 3, 1991
    Assignee: Polysar Limited
    Inventors: Stephen C. Davis, Janet B. Fulton, Peter P. M. Hoang
  • Patent number: 5043392
    Abstract: Functionalized thermoplastics such as styrene-maleic anhydride copolymers polystyrene or maleated polyolefins may be thoughened with halogenated rubbers which are copolymers of isoprene and isobutylene provided a dialkyl or dihydroxyalkyl amino alkanol is present as a compatibilizer. The toughened thermoplastics have about a two fold increase in IZOD impact resistance.
    Type: Grant
    Filed: January 22, 1990
    Date of Patent: August 27, 1991
    Assignee: Polysar Limited
    Inventors: James Lunt, Susan A. M. May, Patricia A. Leivo
  • Patent number: 5026744
    Abstract: A nontacky, shock absorbing rubber composition suitable for replacing the natural clay used in horseshoe pits to absorb the energy of a thrown horseshoe, said composition comprising butyl rubber, crosslinked butyl rubber, cellulose fibre, particulate filler and plasticizer.
    Type: Grant
    Filed: January 17, 1989
    Date of Patent: June 25, 1991
    Assignee: Polysar Limited
    Inventor: Keith A. Callander
  • Patent number: 5026794
    Abstract: This invention provides an adduct of an epoxy resin and a hydroxy free acrylate resin. The novel adduct contains vinyl unsaturation and hence may be copolymerized with an ethylenically unsaturated monomer to provide a tough thermoset resin.
    Type: Grant
    Filed: May 23, 1989
    Date of Patent: June 25, 1991
    Assignee: Polysar Limited
    Inventors: Kam W. Ho, Patrick W. Lam
  • Patent number: 4990456
    Abstract: The rubber content in a low gel rubber modified asphalt may be accurately and rapidly determined using gel permeation chromatography in which one or more columns comprise glass particles having a size from 80/120 mesh to 200/400 mesh and a pore size from 75 to 120A. The analysis may be automated and is faster and more accurate than currently used procedures.
    Type: Grant
    Filed: October 31, 1988
    Date of Patent: February 5, 1991
    Assignee: Polysar Limited
    Inventors: Dennis A. Loucks, Frederick P. Seguin
  • Patent number: 4985540
    Abstract: A process is provided for removing rhodium-containing catalyst residue from a solution of hydrogenated nitrile rubber. The process utilizes an ion exchange resin which must be both macroreticular and modified with a selected amine, thiol, carbodithioate, thiourea and/or dithiocarbamate functional group. The process is capable of removing rhodium from viscous rubber solutions containing less than 10 ppm rhodium. In a preferred embodiment, the process is undertaken in an ion-exchange column.
    Type: Grant
    Filed: November 20, 1989
    Date of Patent: January 15, 1991
    Assignee: Polysar Limited
    Inventors: William G. Bradford, Gilles J. Arsenault, Alexander J. Marshall
  • Patent number: 4983528
    Abstract: A method is provided for quantitatively determining the amount of unsaturation in butyl and EPDM rubbers using a gel permeation chromatograph in combination with an ultraviolet detector. Placement of a differential refractive index detector in series with said ultraviolet detector provides a method for the simultaneous measurement of the amount of unsaturation, the molecular weight distribution and the amount of antioxidant in said rubbers.
    Type: Grant
    Filed: June 6, 1989
    Date of Patent: January 8, 1991
    Assignee: Polysar Limited
    Inventor: Dennis A. Loucks
  • Patent number: 4980406
    Abstract: The present invention relates to thermosetting polyacrylate compositions having surprising impact strength and glass transition temperature properties.The compositions are prepared with a selected acrylate monomer, a copolymerizable unsaturated monomer, and a selected nitrile rubber and are cured with a free radical curing agent.The compositions are suitable for use in molding compounds.
    Type: Grant
    Filed: July 22, 1988
    Date of Patent: December 25, 1990
    Assignee: Polysar Limited
    Inventor: Patrick W. Lam
  • Patent number: 4959420
    Abstract: A chlorinated ethylene-alpha olefin-nonconjugated diolefin terpolymer having a chlorine content of from about 0.5 to 14 percent by weight characterized by superior viscosity stability on storage or exposure to elevated temperatures is obtained by chlorinating an ethylene-alpha olefin-nonconjugated diolefin terpolymer wherein said nonconjugated diolefin is an acyclic nonconjugated diolefin characterized in that one olefinic bond is monosubstituted and terminal and the other olefinic bond is trisubstituted. A vulcanizable rubber composition comprising said chlorinated ethylene-alpha olefin-nonconjugated diolefin terpolymer and cure active agents is also provided.
    Type: Grant
    Filed: November 1, 1989
    Date of Patent: September 25, 1990
    Assignee: Polysar Limited
    Inventors: Stephen C. Davis, Janet B. Fulton, Peter P. M. Hoang
  • Patent number: 4956398
    Abstract: The present invention provides a silica filled composition which contains vinyl chloride polymer and a nitrile rubber. The silica is characterized by being coated with a polymer which is prepared by the free radical emulsion polymerization of acrylate monomer. The compositions of the present invention have a good balance of physical properties and outstanding resistance to crack growth and hence are suitable for the manufacture of mechanical goods.
    Type: Grant
    Filed: June 7, 1989
    Date of Patent: September 11, 1990
    Assignee: Polysar Limited
    Inventors: Abdul L. Ayub, Herbert F. Schwarz
  • Patent number: 4944926
    Abstract: The present invention provides a method to treat a rhodium containing solution which is derived from the catalytic hydrogenation of nitrile rubber.An additive selected from thiourea, polysaccharide and carbon black is used to cause a rhodium-containing precipitate. The precipitate is then separated from the solution by, for example, filtration or centrifugation.
    Type: Grant
    Filed: August 1, 1988
    Date of Patent: July 31, 1990
    Assignee: Polysar Limited
    Inventors: Akhtar Osman, William G. Bradford
  • Patent number: 4943616
    Abstract: A polymerization process is provided for producing a terminally functional polymer which comprises introducing a monomer charge, a Lewis acid and an organic peroxy compound into a suitable reaction vessel and polymerizing the monomer charge at a temperature of from about 0.degree. to about -80.degree. C. to form the terminally functional polymer, wherein the monomer charge comprises isobutylene and the organic peroxy compound is charged in an amount of from about 10.sup.-4 to about 10.sup.-1 moles per mole of the isobutylene. In a preferred embodiment, the monomer charge additionally comprises vinylidene aromatic or diolefin monomers. In another preferred embodiment the monomer charge comprises the sequential addition of isobutylene and vinylidene aromatic or diolefin monomers. In a further preferred embodiment said reaction vessel is additionally charged with an electron door having an electron door number of from about 22 to about 50 the amount of said electron door being from about 10.sup.-4 to about 10.
    Type: Grant
    Filed: December 4, 1989
    Date of Patent: July 24, 1990
    Assignee: Polysar Limited
    Inventors: Munmaya K. Mishra, Akhtar Osman
  • Patent number: 4942920
    Abstract: The present invention relates to a convenient process to detect leaks in a partially disassembled floating head-type heat exchanger. The heat exchanger is partially disassembled by removing the floating head end shell cover. A lightweight, flexible membrane having low gas permeability is then attached to the exchanger so as to cover the floating head gap. Gas is then introduced into the shell side of the exchanger.Leaks may be detected by observing the end face of the floating head tube sheet for an indication of the gas using a soap solution and observing the formation of soap bubbles.
    Type: Grant
    Filed: April 27, 1989
    Date of Patent: July 24, 1990
    Assignee: Polysar Limited
    Inventors: Raymond J. Chalifoux, John Kozachuk
  • Patent number: 4925715
    Abstract: The present invention relates to a tension wound roll of tape. The tape does not contain a separate adhesive layer but will bond to itself after being elongated by at least 50 percent and wrapped in overlapping layers. The tape of the invention will not self fuse when in roll form. The present tape is prepared from a minor proportion of a thermoplastic polymer and a major proportion of elastomeric polymer, and further contains a minor amount of an anti-blocking agent. The tape may be used in a wide variety of applications, for example, to repair leaks in hoses or pipes.
    Type: Grant
    Filed: June 7, 1989
    Date of Patent: May 15, 1990
    Assignee: Polysar Limited
    Inventor: Kyosaku Sato