Patents by Inventor Gaddam N. Babu

Gaddam N. Babu 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: 6245922
    Abstract: A photoactive compound that is the reaction product of an alkenyl azlactone compound and a nucleophilic aromatic ketone is described. Mer units derived from this compound can be used, for example, to crosslink via a hydrogen abstracting mechanism acrylic polymers in which they are incorporated.
    Type: Grant
    Filed: November 19, 1996
    Date of Patent: June 12, 2001
    Assignee: 3M Innovative Properties Company
    Inventors: Steven M. Heilmann, Gaddam N. Babu, Larry R. Krepski, Howell K. Smith, II, Daniel E. Mickus
  • Patent number: 5968652
    Abstract: The present invention encompasses novel coated particles that are well suited for use as absorption media in chromatographic processes. The coated particles comprise a substrate, such as aluminum, silicon, titanium or zirconium oxide particles, containing polymerized silane moieties on a surface of the substrate. The silane moieties include two or three olefinic groups as well as at least on useful ligand. Methods of preparing these coated particles are also described.
    Type: Grant
    Filed: November 10, 1998
    Date of Patent: October 19, 1999
    Assignee: 3M Innovative Properties Company
    Inventors: Douglas A. Hanggi, Gaddam N. Babu, Terry L. Davis
  • Patent number: 5908700
    Abstract: A moisture-curable, hot melt composition comprising a graft polyurethane prepolymer made by reacting a macromonomer, polyol, polyisocyanate and optional silane reagent is provided. The composition advantageously provides adhesives having initial creep resistance, short set times, and long open times.
    Type: Grant
    Filed: June 9, 1997
    Date of Patent: June 1, 1999
    Assignee: Minnesota Mining & Manufacturing Company
    Inventors: Yoshinori Shimizu, Gaddam N. Babu, Albert I. Everaerts
  • Patent number: 5902836
    Abstract: Solute polymers in solvent monomers form a coatable syrup that can be cured to a viscoelastomeric material when radiation-sensitive .alpha.-cleaving groups in either the polymer or one of the monomers are exposed to ultraviolet radiation. The solute polymers can be formed from the solvent monomers in situ or be added thereto to form the syrup.
    Type: Grant
    Filed: August 23, 1995
    Date of Patent: May 11, 1999
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Greggory S. Bennett, Gaddam N. Babu, Kejian Chen, Louis E. Winslow, George F. Vesley, Patrick G. Zimmerman
  • Patent number: 5853642
    Abstract: A process that involves the in-line polymerization of olefinic monomer(s) and catalyst systems comprising a transition metal species that mediates the polymerization of the monomer(s) is disclosed. This process provides the immediate use of the resultant polymer without extensive further processing.
    Type: Grant
    Filed: July 29, 1994
    Date of Patent: December 29, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Allen R. Siedle, Gaddam N. Babu, Katherine A. Brown-Wensley, James R. Peterson
  • Patent number: 5773485
    Abstract: Solute polymers in solvent monomers form a coatable syrup that can be cured to a viscoelastomeric material when radiation-sensitive hydrogen abstracting groups in either the polymer or one of the monomers are exposed to ultraviolet radiation. The solute polymers can be formed from the solvent monomers.
    Type: Grant
    Filed: August 23, 1995
    Date of Patent: June 30, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Greggory S. Bennett, Louis E. Winslow, Gaddam N. Babu
  • Patent number: 5753364
    Abstract: The present invention provides pressure sensitive adhesives, compositions from which the pressure sensitive adhesives are formed, and articles having therein these pressure sensitive adhesives. The pressure sensitive adhesives, which have a Tg of less than about 20.degree. C., include a poly(.beta.-hydroxyorganoate) or mixture thereof. Preferably, these poly(.beta.-hydroxyorganoate)s include monomeric units of the general formula: ##STR1## wherein a minor amount (preferably no greater than about 20 mole percent) of the monomeric units have an R group containing 1-3 carbon atoms; and a major amount (preferably at least about 80 mole percent) of the monomeric units have an R group containing 4-30 (preferably 4-20) carbon atoms.
    Type: Grant
    Filed: January 30, 1997
    Date of Patent: May 19, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Denise R. Rutherford, W. James Hammar, Gaddam N. Babu
  • Patent number: 5741543
    Abstract: This invention relates to a process in which a composition is coated onto a substrate and crosslinked so as to form a PSA by means of polymerizing free radically polymerizable monomers from covalently attached pendent unsaturation in the polymer component of the composition. The coating can carried out by a wide variety of industrial methods because the process of the invention allows for compositions with a wide degree of possible viscosities.
    Type: Grant
    Filed: July 18, 1996
    Date of Patent: April 21, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Louis E. Winslow, Greggory S. Bennett, Gaddam N. Babu, Paul Hattam, Michael L. Tumey, Bhaskar V. Velamakanni
  • Patent number: 5667674
    Abstract: An adsorption medium that includes a finely divided substrate provided on at least a portion of its surface with the polymerization product of a silane that includes (a) two or three olefinic groups having the formula --(CH.sub.2).sub.m CH.dbd.CH.sub.2, where m is between 0 and 3, inclusive, and (b) at least one ligand selected to interact with a substance brought into contact with the adsorption medium to adsorb at least a portion of the substance on the surface of the adsorption medium.
    Type: Grant
    Filed: January 11, 1996
    Date of Patent: September 16, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Douglas A. Hanggi, Gaddam N. Babu, Terry L. Davis
  • Patent number: 5614576
    Abstract: The present invention provides pressure sensitive adhesives, compositions from which the pressure sensitive adhesives are formed, and articles having therein these pressure sensitive adhesives. The pressure sensitive adhesives, which have a Tg of less than about 20.degree. C., include a poly(.beta.-hydroxyorganoate) or mixture thereof. Preferably, these poly(.beta.-hydroxyorganoate)s include monomeric units of the general formula: ##STR1## wherein: a minor amount (preferably no greater than about 20 mole percent) of the monomeric units have an R group containing 1-3 carbon atoms; and a major amount (preferably at least about 80 mole percent) of the monomeric units have an R group containing 4-30 (preferably 4-20) carbon atoms.
    Type: Grant
    Filed: April 15, 1996
    Date of Patent: March 25, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Denise R. Rutherford, W. James Hammar, Gaddam N. Babu
  • Patent number: 5578380
    Abstract: Crosslinkable copolymers suitable for use as elevated temperature pressure-sensitive adhesives comprise randomly arranged silarylene units and siloxane units. Preferably, there is present in the copolymer backbone in the range of 0.8 to 1.2 siloxane to silarylene units, and there being present in the copolymer a crosslinking functionality.
    Type: Grant
    Filed: May 27, 1994
    Date of Patent: November 26, 1996
    Inventor: Gaddam N. Babu
  • Patent number: 5559164
    Abstract: Compositions radiation-curable to pressure sensitive adhesives comprise (1) one or more copolymers of .alpha.-olefins of which 90.1 to 99 mole percent are one or more straight chain .alpha.-olefins, having 2 to 10 carbon atoms of which at least 55% have 6 to 10 carbon atoms, and 9.9 to 0.1 mole percent are one or more .alpha.-olefins having 6 to 20 carbon atoms and at least one methylidyne group; (2) an effective amount of a photoactive hydrogen abstracting agent; and, optionally, (3) a tackifying resin. The compositions, on exposure to radiation, provide adhesive films useful in adhesive applications, especially where a bonded article is to be used at elevated temperatures.
    Type: Grant
    Filed: December 2, 1994
    Date of Patent: September 24, 1996
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Gaddam N. Babu, James R. Peterson
  • Patent number: 5506279
    Abstract: The invention provides novel acrylamide functional disubstituted acetyl aryl ketones and a process for their preparation in high yields uncontaminated by difunctional material. The invention further provides photocrosslinkable compositions comprising one or more ethylenically-unsaturated monomers and as photoinitiator the acrylamide functional disubstituted acetyl aryl ketone of the invention. The compositions are useful for the preparation of films and coatings, particularly pressure-sensitive adhesive coatings.
    Type: Grant
    Filed: May 3, 1994
    Date of Patent: April 9, 1996
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Gaddam N. Babu, Greggory S. Bennett, Kejian Chen, Steven M. Heilmann, Howell K. Smith, II, Louis E. Winslow
  • Patent number: 5428209
    Abstract: A piece of microwave-active tape which is odor-free and physiologically inert can be adhered to a food package and remains strongly adhered during cooking at temperatures of at least 200.degree. C. The tape has layers of microwave-active material and a pressure-sensitive adhesive which is a polymeric .alpha.-olefin that has been cured to afford a "Peel Value" of at least 5 N/dm and a "Shrink Back" at 220.degree. C. of less than 5%. The tape can have a flexible backing such as a low-adhesion carrier web which can be stripped off from a piece of the tape that has been applied to a microwave food package, or when the backing is heat-resistant, it can be left in place.
    Type: Grant
    Filed: December 7, 1993
    Date of Patent: June 27, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Gaddam N. Babu, Susan S. Christopher, Pierre H. LePere, James R. Peterson
  • Patent number: 5407970
    Abstract: The invention relates to adhesive compositions comprising terpolymers C.sub.6 to C.sub.10 unsaturated .alpha.-olefin monomers, C.sub.2 to C.sub.5 .alpha.-olefin monomers and polyene monomers and an effective amount of photoactive cross-linking agent to cross-link composition upon radiation from a source of active radiation.
    Type: Grant
    Filed: April 13, 1993
    Date of Patent: April 18, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: James R. Peterson, Gaddam N. Babu
  • Patent number: 5401792
    Abstract: Sprayable hot-melt adhesive compositions are disclosed comprising (A) styrenic block copolymer, (B) tackifying resin, and (C) ethylene copolymer. Methods of preparing and using said compositions are also disclosed.
    Type: Grant
    Filed: November 10, 1993
    Date of Patent: March 28, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Gaddam N. Babu, Dennis D. Hansen
  • Patent number: 5397648
    Abstract: A pressure-sensitive adhesive comprises a moisture-curable polymer comprising a polymer prepared by polymerization of at least one .alpha.-olefin monomer, said polymer containing hydrolyzable or condensable silyl groups and having a weight average molecular weight of at least 30,000. The pressure-sensitive adhesive can be hot-melt coated without emitting volatiles and then can adhere aggressively to both polar and nonpolar substrates. The PSA has good internal strength at high temperatures.
    Type: Grant
    Filed: December 21, 1993
    Date of Patent: March 14, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Gaddam N. Babu, James R. Peterson, Sehyun Nam
  • Patent number: 5354619
    Abstract: The invention provides pressure-sensitive adhesive (PSA) compositions comprising a graft copolymer of one or more of ethylene and C.sub.3 -C.sub.18 .alpha.-olefins and one or more of a new class of macromonomers. The adhesive composition comprises a blend of the graft copolymer with a tackifying resin. Sheet materials can be coated with layers of the adhesive composition to provide tapes and laminates.
    Type: Grant
    Filed: December 21, 1993
    Date of Patent: October 11, 1994
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Gaddam N. Babu
  • Patent number: 5346980
    Abstract: Crosslinkable copolymers suitable for use as elevated temperature pressure-sensitive adhesives comprise randomly arranged silarylene units and siloxane units. Preferably, there is present in the copolymer backbone in the range of 0.8 to 1.2 siloxane to silarylene units, and there being present in the copolymer a crosslinking functionality.
    Type: Grant
    Filed: January 28, 1993
    Date of Patent: September 13, 1994
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Gaddam N. Babu
  • Patent number: 5298708
    Abstract: A piece of microwave-active tape which is odor-free and physiologically inert can be adhered to a food package and remains strongly adhered during cooking at temperatures of at least 200.degree. C. The tape has layers of microwave-active material and a pressure-sensitive adhesive which is a polymeric .alpha.-olefin that has been cured to afford a "Peel Value" of at least 5 N/dm and a "Shrink Back" at 220.degree. C. of less than 5%. The tape can have a flexible backing such as a low-adhesion carrier web which can be stripped off from a piece of the tape that has been applied to a microwave food package, or when the backing is heat-resistant, it can be left in place.
    Type: Grant
    Filed: February 7, 1991
    Date of Patent: March 29, 1994
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Gaddam N. Babu, Susan S. Christopher, Pierre H. LePere, James R. Peterson