Patents by Inventor Leonard R. Hepp

Leonard R. Hepp 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).

  • Preparation of linear polyester-polyepoxide reaction products via reactive concentrate
    Patent number: 4904746
    Abstract: Branched polyester compositions having high melt viscosities, especially under conditions of low shear, are prepared in a two-step method. The first step is the reaction of a linear polyester, polycarbonate or polyester-polycarbonate containing free carboxylic acid groups with a polyfunctional epoxyalkyl compound such as triglycidyl isocyanurate to form a reactive concentrate. The second step is the reaction of said reactive concentrate with a polyester, such as poly(ethylene terephthalate) or poly(butylene terephthalate), containing a measurable proportion of carboxylic acid end groups. By this two-step method, it is possible to use less epoxy compound for a given melt viscosity level than is the case when the epoxy compound is directly blended with the polyester.
    Type: Grant
    Filed: April 21, 1988
    Date of Patent: February 27, 1990
    Assignee: General Electric Company
    Inventors: Sterling B. Brown, Choong Y. Han, James L. DeRudder, Leonard R. Hepp
  • Glass fiber reinforced polyester molding compositions containing metal salts
    Patent number: 4687802
    Abstract: Metal salts are disclosed as effective to reduce Arc Track Rate in poly(1,4-butylene terephthalate) resin molding compositions.
    Type: Grant
    Filed: February 25, 1985
    Date of Patent: August 18, 1987
    Assignee: General Electric Company
    Inventor: Leonard R. Hepp
  • Glass fiber reinforced polyester molding compositions containing metal powders
    Patent number: 4684686
    Abstract: Particulate and fibrous metal are disclosed to improve the physical properties of poly(1,4-butylene terephthalate) resin molding compositions.
    Type: Grant
    Filed: February 25, 1985
    Date of Patent: August 4, 1987
    Assignee: General Electric Company
    Inventor: Leonard R. Hepp
  • Flame retarded polyester molding composition with improved electrical performance
    Patent number: 4636544
    Abstract: Titanium dioxide is disclosed to improve the comparative tracking index of flame retarded poly(1,4-butylene terephthalate) resin molding compositions.
    Type: Grant
    Filed: February 25, 1985
    Date of Patent: January 13, 1987
    Assignee: General Electric Company
    Inventor: Leonard R. Hepp
  • Flame retarded polyester resin with improved impact strength
    Patent number: 4629750
    Abstract: Cuprous iodide is disclosed to improve the impact strength of flame retarded, glass reinforced, impact modified, poly(1,4-butylene terephthalate) resin molding compositions.
    Type: Grant
    Filed: February 25, 1985
    Date of Patent: December 16, 1986
    Assignee: General Electric Company
    Inventor: Leonard R. Hepp
  • Reinforced thermoplastic composition
    Patent number: 4436860
    Abstract: Improved heat-resistant composition producing injection molded workpieces which are opaque and crystalline in thin, thick and large/flat parts comprise a combination consisting predominantly of poly(ethylene terephthalate) with a lesser proportion of poly(1,4-butylene terephthalate), such combination being reinforced with filamentous glass and, optionally, but preferably, containing an internal nucleating amount of sodium stearate.
    Type: Grant
    Filed: May 24, 1983
    Date of Patent: March 13, 1984
    Assignee: General Electric Company
    Inventor: Leonard R. Hepp
  • Impact modified glass/mineral reinforced polyester blends
    Patent number: 4393153
    Abstract: The addition of poly(ethylene terephthalate) to core-shell resin impact modified, glass fiber and mica reinforced poly(1,4-butylene terephthalate) compositions provides articles molded therefrom with improved surface gloss, impact strength, flexural modulus, flexural strength and tensile strength. Heat distortion temperatures are elevated if not less than 2.6 nor more than 4 parts by weight of poly(1,4-butylene terephthalate) resin is present for each 1 part by weight of acrylic resin impact modifier.
    Type: Grant
    Filed: October 30, 1981
    Date of Patent: July 12, 1983
    Assignee: General Electric Company
    Inventor: Leonard R. Hepp