Patents by Inventor Ronald A. Zelonka

Ronald A. Zelonka 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).

  • Patent number: 4777229
    Abstract: A solution polymerization process for the preparation of high molecular weight polymers selected from the group consisting of homopolymers of ethylene and copolymers of ethylene and butene-1 is disclosed. The process comprises feeding monomer(s), coordination catalyst and inert hydrocarbon solvent to a reactor, polymerizing the monomers at a temperature of up to 320.degree. C. and a pressure of less than 25 MPa, and deactivating the catalyst in the solution so obtained. The catalyst is deactivated by sequentially admixing therewith a minor amount of dimethyl carbonate followed by a solution of a salt of an alkaline earth metal or zinc and an aliphatic monocarboxylic acid dissolved in hydrocarbon solvent. The hydrocarbon solvent and other volatile matter are then separated from the resultant solution and a composition comprising the high molecular weight polymer is recovered. The amount of dimethyl carbonate is not more than 2.5 moles, per mole of halogen plus alkyl radicals in the coordination catalyst.
    Type: Grant
    Filed: September 14, 1987
    Date of Patent: October 11, 1988
    Assignee: Du Pont Canada Inc.
    Inventors: Vaclav G. Zboril, Ronald A. Zelonka
  • Patent number: 4678834
    Abstract: A polyolefin blend comprising, in physical admixture, a major portion of particles of a polyethylene and a minor portion of particles of a composition of a thermoplastic second polymer, is disclosed. The polyethylene is selected from the group consisting of homopolymers of ethylene and copolymers of ethylene and at least one C.sub.4 -C.sub.10 higher alpha-olefin, and the second polymer is a normally solid thermoplastic polymer having a melting point of less than 185.degree. C. and a shear viscosity that is not more than that of the polyethylene when measured at 200.degree. C. and a shear rate of 400 sec.sup.-1 with the proviso that the second polymer is not a homopolymer or copolymer derived solely from hydrocarbon alpha-olefins having 2-10 carbon atoms. Examples of second polymers are (a) homopolymers and copolymers of unsaturated hydrocarbons in which at least one monomer is other than a C.sub.2 -C.sub.10 alpha-olefin, e.g.
    Type: Grant
    Filed: July 18, 1985
    Date of Patent: July 7, 1987
    Assignee: Du Pont Canada Inc.
    Inventors: Daniel W. Boivin, Ronald A. Zelonka
  • Patent number: 4612155
    Abstract: A continuous process for the grafting of ethylenically unsaturated monomers onto homopolymers of ethylene and copolymers of ethylene and C.sub.4 -C.sub.10 higher alpha-olefins is disclosed. The process involves feeding to an extruder an admixture comprising (i) a major portion of the above polymer of ethylene, (ii) the monomer, (iii) 25-500 ppm of an organic peroxide and (iv) a minor portion of a normally solid thermoplastic polymer having a melting point of less than 185.degree. C. and a shear viscosity at 200.degree. C. and a shear rate of 400 sec.sup.-1 that is not more than 50% of that of the polymer of ethylene. The organic peroxide is in the form of a composition with the thermoplastic polymer. The admixture is mixed in a first zone at a temperature above the melting point of the polymers for at least ten seconds but for less than 25% decomposition of the peroxide and then in a second zone for a period that is at least four times the half-life of the peroxide.
    Type: Grant
    Filed: July 18, 1985
    Date of Patent: September 16, 1986
    Assignee: Du Pont Canada Inc.
    Inventors: Chun S. Wong, Ronald A. Zelonka
  • Patent number: 4341907
    Abstract: A process is disclosed for the catalytic oxidation of a cycloparaffin, e.g., cyclohexane, to partial oxidation products thereof, especially for the production of mixtures of cycloalkanols and cycloalkanones. In the process, molecular oxygen, usually in the presence of an inert gas, is introduced into the cycloparaffin at elevated pressure and a temperature of 130.degree.-180.degree. C., in the presence of an oxidation catalyst comprising a heavy metal compound along with an N-heterocyclic compound. The heavy metal of the heavy metal compound may be cobalt, vanadium, manganese, copper, iron or nickel. The heavy metal compound may have ligands of alkanoate, dialkylphosphate, dicycloalkylphosphate or alkylcycloalkylphosphate. The N-heterocyclic compound may be dipyridyl, pyrimidine, pyrazine, pyridine and pyridine substituted with --CN, --R, and/or --OR where R is alkyl. A preferred catalyst is cobalt bis[di(2-ethylhexyl)phosphate] in combination with pyridine.
    Type: Grant
    Filed: January 30, 1981
    Date of Patent: July 27, 1982
    Assignee: Du Pont Canada Inc.
    Inventor: Ronald A. Zelonka