Patents by Inventor Zhi-Zhong Liang

Zhi-Zhong Liang 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: 6737443
    Abstract: Methods for making the stable dispersion of lignin components of black liquor in bitumen. Representative methods comprising converting an aqueous colloidal dispersion of lignin in spent pulping liquor to an anhydrous colloidal dispersion of lignin in a lubricating oil by mixing a lubricating oil with the spent pulping liquor, and dewatering the mixture so formed at an elevated temperature to form a cream-like paste compatible with bitumen, and mixing said anhydrous colloidal dispersion of lignin with bitumen.
    Type: Grant
    Filed: November 20, 2000
    Date of Patent: May 18, 2004
    Assignee: Polyphalt Inc.
    Inventor: Zhi-Zhong Liang
  • Patent number: 6579921
    Abstract: Roofing membranes are provided with both high stiffness at high temperature (greater than 110 ° C.) and good flexibility at low temperature (less than −20 ° C.). Bituminous compositions may be more effectively used in such membranes at lower elastomer concentration than currently practiced, using conventional cross-linking reagents to prepare the modified bituminous compositions with a range of viscosities that are readily processed as compared with conventional non-cross-linked systems.
    Type: Grant
    Filed: September 24, 2001
    Date of Patent: June 17, 2003
    Assignee: Polyphalt Inc.
    Inventors: Zhi Zhong Liang, Yan-Ping Zhang
  • Publication number: 20030036590
    Abstract: A stable dispersion of polyethylene and other polyolefins in a continuous bituminous phase is provided by dissolving macromolecular material into the bitumen to create a potential energy barrier to coalescence and flocculation of the polymer dispersion.
    Type: Application
    Filed: October 15, 2002
    Publication date: February 20, 2003
    Inventor: Zhi-zhong Liang
  • Publication number: 20030032703
    Abstract: Polymer modified bituminous compositions which are stable against phase separation are provided at greater levels of incorporation of elastomeric polymer having a conjugated diene structure, such as styrene-butadiene rubbers, and/or cross-linking agent, specifically sulfur, by incremental addition of elastomeric polymer and/or cross-linking agent into the bitumen at elevated temperatures of about 150° to about 220° C.
    Type: Application
    Filed: June 12, 2002
    Publication date: February 13, 2003
    Inventor: Zhi-Zhong Liang
  • Patent number: 6429241
    Abstract: Polymer modified bituminous compositions which are stable against phase separation are provided at greater levels of incorporation of elastomeric polymer having a conjugated diene structure, such as styrene-butadiene rubbers, and/or cross-linking agent, specifically sulfur, by incremental addition of elastomeric polymer and/or cross-linking agent into the bitumen at elevated temperatures of about 150° to about 220° C.
    Type: Grant
    Filed: December 2, 1999
    Date of Patent: August 6, 2002
    Assignee: Polyphalt LLC
    Inventor: Zhi-Zhong Liang
  • Patent number: 6174939
    Abstract: Normally incompatible styrenic polymers are stably incorporated into bitumen by using an elastomeric triblock copolymer comprising polystyrene segments which is solubilized or compatibilized in the bituminous phase. The elastomeric triblock copolymer incorporated into the continuous bituminous phase provides polystyrene domains which are dispersed throughout the bitumen or a receiving unit which stabilize the particulate polystyrene against separation from the bitumen.
    Type: Grant
    Filed: May 7, 1999
    Date of Patent: January 16, 2001
    Assignee: Polyphalt Inc.
    Inventor: Zhi-Zhong Liang
  • Patent number: 6100317
    Abstract: Two or more different polymeric materials are stably incorporated into bitumen by effecting steric stabilization of a polyolefin, such as polyethylene, and by dispersing the other polymer, such as a styrene-butadiene-styrene copolymer, an ethylene-vinyl acetate copolymer or an EPDM copolymer in the stabilized polyethylene-bitumen composition. The ability to incorporate different polymeric materials in bitumen permits desirable modifications to the properties of the composition to be effected. In addition, different properties can be attained by modifying processing parameters.
    Type: Grant
    Filed: August 13, 1996
    Date of Patent: August 8, 2000
    Assignee: Polyphalt L.L.C.
    Inventors: Zhi-zhong Liang, Raymond T. Woodhams, James W. Smith
  • Patent number: 5959007
    Abstract: Stable rubberized bitumen concentrates are prepared by initially forming a mass comprising bitumen and crumb rubber particles in an amount of at least about 15 wt % of the mass with the crumb rubber being swollen in-situ, and applying shear and temperature conditions to the mass to dissociate the vulcanizate network of the rubber particles and to incorporate the digested vulcanizate into the bitumen. The stable rubberized bitumen concentrate is stable against sedimentation of rubber particles both following storage of the concentrate at about 320.degree. F. for 48 hours and dilution to a lower concentration in the ASTM solubility test.
    Type: Grant
    Filed: November 20, 1997
    Date of Patent: September 28, 1999
    Assignee: Polyphalt L.L.C.
    Inventor: Zhi-Zhong Liang
  • Patent number: 5719215
    Abstract: The present invention provides a procedure for at least partial dissociation of crumb rubber vulcanate network, including automobile tires, and for the incorporation of this treated rubber into stable bitumen compositions. The at least partially dissociated rubber vulcanate network may be used independently as a bitumen modifier, or a stabilizing agent for ground vulcanate rubber dispersions in bitumen or as a steric stabilizer in dispersion of polyolefins in bitumen. The at least partially dissociated rubber vulcanate network materials are produced in situ in bitumen or produced separately and subsequently incorporated into bitumen and the bituminous compositions are useful materials for a variety of applications. Modifications are possible within the scope of this invention.
    Type: Grant
    Filed: September 12, 1995
    Date of Patent: February 17, 1998
    Assignee: Polyphalt L.L.C.
    Inventors: Zhi-zhong Liang, Raymond T. Woodhams
  • Patent number: 5705564
    Abstract: Insoluble particulate materials, which may be in solid or liquid form, are dispersed in a continuous non-aqueous phase and the dispersion rendered stable and resistant to phase separation by an in-situ stabilization procedure involving the formation of chemical bonds among the stabilizer components and to dispersed phases to form a network surrounding the particles which is compatible with the continuous phase. The invention has particular application for the formation of stabilized polyolefin-modified bitumen compositions for paving and other applications.
    Type: Grant
    Filed: November 28, 1995
    Date of Patent: January 6, 1998
    Assignee: The University of Toronto Innovations Foundation
    Inventors: Zhi-Zhong Liang, Raymond T. Woodhams