Patents by Inventor Evalds Lasis

Evalds Lasis has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Low benzene butadiene polymerization
    Patent number: 4242478
    Abstract: A process is provided for the polymerization of butadiene-1,3 to yield a high cis-1,4-polybutadiene in which the diluent for the polymerization is a mixture of cyclohexane and either or both of benzene and butene-1, wherein the amount of benzene is markedly reduced in comparison with that generally used. The polybutadiene may be used in the manufacture of tires and in impact polystyrene.
    Type: Grant
    Filed: April 12, 1979
    Date of Patent: December 30, 1980
    Assignee: Polysar Limited
    Inventor: Evalds Lasis
  • Aldehyde modified polymers
    Patent number: 4168369
    Abstract: Synthetic elastomer compositions of high green strength comprise the reaction product of a rubbery polymer of a conjugated alkadiene having a small number of aldehyde groups attached to and randomly distributed along the polymer chain, and a polyamine having at least two non-tertiary amine groups. An example is a copolymer of styrene, butadiene and cinnamaldehyde (0.5 parts by weight) reacted with p-phenylene diamine, in an amount of 1 mole diamine per mole of cinnamaldehyde.
    Type: Grant
    Filed: June 28, 1974
    Date of Patent: September 18, 1979
    Assignee: Polysar Limited
    Inventors: Evalds Lasis, Ernest J. Buckler
  • Amine modified polymers reacted with halogen compounds
    Patent number: 4070340
    Abstract: Synthetic rubber compositions of improved green strength are prepared by incorporating in a synthetic rubber polymer, such as NBR or SBR, a small number of tertiary amine groups, and reacting this polymer with a halogen compound of general formula X--CH.sub.2 --R--CH.sub.2 --Y where X and Y represent chlorine, bromine or iodine, and R represents an aromatic group, and where X and Y are capable of forming quaternary ammonium salts with the tertiary amine groups on the polymer.
    Type: Grant
    Filed: March 26, 1976
    Date of Patent: January 24, 1978
    Assignee: Polysar Limited
    Inventors: Evalds Lasis, Ernest Jack Buckler
  • Amine modified polymers
    Patent number: 3969330
    Abstract: Synthetic rubber compositions of improved green strength are prepared by incorporating in a synthetic rubber polymer, such as NBR or SBR, a small number of tertiary amine groups, and reacting this polymer with a halogen compound containing two or more halogen atoms capable of forming quarternary ammonium salts with the tertiary amine groups on the polymer. 1,4-dibromobutene-2 is a suitable halogen compound. The tertiary amine groups can be incorporated by copolymerizing dimethylaminoethyl acrylate with the rubbery copolymer forming monomers.
    Type: Grant
    Filed: September 30, 1974
    Date of Patent: July 13, 1976
    Assignee: Polysar Limited
    Inventors: Evalds Lasis, Ernest Jack Buckler