Patents by Inventor Peter Loewrigkeit

Peter Loewrigkeit 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: 4644030
    Abstract: Method of making a stable aqueous dispersion of polymeric material comprising:(A) producing an NCO-terminated polyurethane prepolymer in the presence of inert liquid polymerizable ethylenically unsaturated monomer material,(B) dispersing the product from A in water,(C) chain-extending the prepolymer in the resulting aqueous dispersion, and(D) subjecting the aqueous dispersion from C to vinyl addition polymerization conditions to polymerize said monomer material in situ, the weight ratio of chain extended polyurethane to said monomer material being about 9:1 to about 1:9., the resulting aqueous dispersions, and their use for making films, sheets and other products.
    Type: Grant
    Filed: February 1, 1985
    Date of Patent: February 17, 1987
    Assignee: Witco Corporation
    Inventors: Peter Loewrigkeit, Kenneth A. Van Dyk
  • Patent number: 4521460
    Abstract: A stable aqueous dispersion of a room temperature curing polymer effective for forming films resistant to water and organic solvents, said polymer being a water-dispersible vinyl addition polymer containing a sufficient proportion of pendant N-methylolhydrazide groups to cause the polymer to cure in situ on a substrate when said dispersion is applied to the substrate and dried at ambient temperature. The polymer preferably sufficient pendant carboxylic salt groups to render the polymer water-dispersible or water soluble.
    Type: Grant
    Filed: June 10, 1983
    Date of Patent: June 4, 1985
    Inventors: Shmuel Dabi, Peter Loewrigkeit, Kenneth A. Van Dyk
  • Patent number: 4447571
    Abstract: A process for providing water based anionic polyurethanes having improved thermal oxidation color stability. Water dispersed amine salts of anionic prepolymers prepared from the reaction of polyhydroxy compounds and dihydroxy carboxylic acids with diisocyanates are chain-extended with hydrazine or hydrazide and thereafter optionally with a diamine, when cured at temperatures in excess of 150.degree. C., form polyurethane products having substantially no discoloration and good mechanical properties. Alternately, the hydrazide may be employed as an additive rather than as a chain-extender. The process is particularly useful when employing cross-linking agents which react only at high temperatures.
    Type: Grant
    Filed: October 15, 1981
    Date of Patent: May 8, 1984
    Assignee: Witco Chemical Corporation
    Inventors: Shmuel Dabi, Peter Loewrigkeit
  • Patent number: 4404258
    Abstract: A polyurethane coated polyvinyl chloride or co-polymer which resists discoloration is provided by coating the substrate surface with an aqueous dispersed polyurethane treated with a mono-acid halide, mono-acid anhydride, carbethoxy cyclic imide or monoisocyanate. The coated composite even when subjected to temperatures in excess of 100 degrees C. for extended periods resists discoloration and remains thermo-color stable with extended use.
    Type: Grant
    Filed: March 26, 1982
    Date of Patent: September 13, 1983
    Assignee: Witco Chemical Corporation
    Inventors: Peter Loewrigkeit, Shmuel Dabi
  • Patent number: 4335029
    Abstract: A stable aqueous dispersion latex of a room temperature curing polyurethane forming films resistant to water and organic solvents is disclosed, the polyurethane containing units derived from melamine, in addition to units derived from diisocyanate and difunctional reactants, in the polymer chain, pendant water-dispersing carboxylic salt groups, and room temperature curable and cross-linking N-methylol hydrazide termini, and methods for making such dispersion.
    Type: Grant
    Filed: December 15, 1980
    Date of Patent: June 15, 1982
    Assignee: Witco Chemical Corporation
    Inventors: Shmuel Dabi, Peter Loewrigkeit, Kenneth A. Van Dyk
  • Patent number: 4160065
    Abstract: A latex suitable for forming improved water-resistant polyurethane products. The latex is prepared in an aqueous system by reacting an NCO-terminated, quaternized, preferably linear, polyurethane prepolymer with water and chain-extending the resulting polyurethane-urea with a difunctional or polyfunctional reagent containing groups reactive with primary amino groups, such as epoxy groups, anhydrides and aldehydes, thus increasing the molecular weight of said polyurethane-urea. The latex thus formed can be dried into highly water-resistant films, coatings, and the like.
    Type: Grant
    Filed: December 14, 1976
    Date of Patent: July 3, 1979
    Assignee: Witco Chemical Corporation
    Inventors: Peter Loewrigkeit, Kenneth A. Van Dyk, Thomas T. McGimpsey
  • Patent number: 4123421
    Abstract: Novel stable substantially linear unsaturated polyurethane resins which lend themselves to polymerization, in air, by actinic light using low levels of photo-initiator and with no amine activator, said resins having a tertiary amine group and a terminal vinylidene group, i.e. H.sub.2 C .dbd. C< by the reaction of an isocyanate with a hydroxyalkyl acrylate or an allyl alcohol monomer. Both the resin and the cured products therefrom have little or no detectable amine odor.
    Type: Grant
    Filed: March 21, 1977
    Date of Patent: October 31, 1978
    Assignee: Witco Chemical Corporation
    Inventors: Richard D. Cowell, Peter Loewrigkeit, William Rosenblatt, Claire Bluestein