Abstract: An electrically nonconductive composite article comprising a fibrillated polytetrafluoroethylene (PTFE) matrix, electrically conductive particles, and electrically nonconductive, energy expanded polymeric particles, which composite upon application of pressure thereto becomes electrically conductive and allows for the flow of electricity through the article. The articles are thin and can be used as a pressure sensitive pad or an interconnect for an electronic component.
Type:
Grant
Filed:
January 31, 1992
Date of Patent:
May 11, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Pressure sensitive adhesive compositions comprise one or more poly(alpha-olefin) homopolymers, copolymers, terpolymers, and tetrapolymers derived from monomers containing 6 to 10 carbon atoms and photoactive crosslinking agents wherein radiation curing provides adhesive films having a superior balance of peel and shear adhesive properties and the pressure sensitive adhesive is useful in pressure sensitive adhesive tapes, in articles containing transfer adhesive films, and as the bonding material between supports in a laminated structure.
Type:
Grant
Filed:
February 3, 1992
Date of Patent:
May 11, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Gaddam N. Babu, Susan S. Christopher, Bruce C. Copley, Thomas S. Overstreet
Abstract: The present invention provides novel fluorinated acrylamide silane monomers which are useful as adhesion promoting agents in optical fiber cladding compositions. Polymerization of the novel monomers, optionally in the presence compatible ethylenically-unsaturated monomers, provides homopolymers and copolymers which are useful as non-wetting agents.
Type:
Grant
Filed:
August 26, 1991
Date of Patent:
May 11, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Stefan A. Babirad, Dean M. Moren, Steven M. Heilmann, Larry R. Krepski, Jerald K. Rasmussen
Abstract: A composite article having controlled void volume and mean pore size comprises:(a) polytetrafluoroethylene (PTFE) fibril matrix, and(b) insoluble, non-swellable sorptive particles enmeshed in said matrix, the ratio of non-swellable sorptive particles to PTFE is in the range of 40:1 to 1:4 by weight, the composite article having a porosity in the range of 30 to 80 percent void volume and a mean pore size in the range of 0.3 to 5 micrometers, preferably with at least 90 percent of pores having a size less than 3.6 micrometers.The article is prepared by incorporating lubricant in the precursor admixture in an amount sufficient to exceed the lubricant sorptive capacity of the particles by at least 3 weight percent and up to an amount at which the mass loses its integrity.
Type:
Grant
Filed:
June 11, 1992
Date of Patent:
May 4, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Donald F. Hagen, Craig G. Markell, William V. Balsimo, Louis A. Errede
Abstract: Polymerization of ring-strained cyclic olefins takes place in the presence of a one-part or two-part catalyst which is air and moisture stable and which comprises a transition metal-containing compound.The one-part transition metal-containing catalyst is selected from the group consisting of(a) compounds of the formula(L.sup.1) (L.sup.2)QwhereinQ represents Mo or W;L.sup.1 represents one to six CO (carbonyl) ligands;L.sup.2 represents none to 5 ligands, each of which is a non-ionic compound or unit of a polymer which can be the same or different, each contributes two, four, or six electrons to the metal and is different from L.sup.1 ;wherein the sum of the valence electrons of Q and the electrons contributed by the ligands L.sup.1 and L.sup.2 is 18,(b) at least one of cationic ruthenium and osmium-containing organometallic salts having at least one polyene ligand, and(c) [Ir(RO.sub.2 CHC=CHCO.sub.2 R).sub.2 Cl].sub.2 wherein each R independently is hydrogen or lower alkyl (C.sub.1 to C.sub.
Type:
Grant
Filed:
December 20, 1991
Date of Patent:
March 30, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Katherine A. Brown-Wensley, Michael C. Palazzotto, William M. Lamanna, Larry D. Boardman, John E. Gozum, Fred B. McCormick
Abstract: A pressure-sensitive adhesive that can adhere aggressively to both polar and nonpolar substrates and has good internal strength at high temperatures is provided by heat or radiation curing a blend of an ethylenically-unsaturated .alpha.-olefin polymer, a crosslinker having at least 2 hydrosilyl groups, and a hydrosilation catalyst. A preferred hydrosilane crosslinker has the formula ##STR1## wherein R is an alkyl group having 1-6 carbon atoms, and n' is a number in the range of 2 to 35.
Type:
Grant
Filed:
October 30, 1990
Date of Patent:
March 16, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: An energy polymerizable composition and process therefore, comprising a cationically polymerizable material and a catalytically effective amount of an ionic salt of an organometallic complex cation as polymerization initiator, said ionic salt of an organometallic complex cation being capable of adding an intermediate strengeth nucleophile or upon photolysis capable of liberating at least one coordination site, said metal in said organometallic complex cation being selected from elements of Periodic Groups IVB, VB, VIB, VIIB, and VIIIB are disclosed. Certain of the organometallic metallic polymerization initiators are novel cationic salts.
Type:
Grant
Filed:
November 26, 1991
Date of Patent:
March 2, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Michael C. Palazzotto, William A. Hendrickson
Abstract: Microcrystalline alpha-alumina based ceramic articles comprising at least 60% alumina by weight, and 0.1-7.0 percent by weight iron equivalence in which substantially all the alumina is in the alpha phase having a uniform grain structure comprising alpha alumina crystallites with an average crystallite size less than 0.5 micrometer and a density greater than 90% theoretical are disclosed. Ceramic articles particularly useful as high modulus refractory fibers, among other shaped bodies such as beads, flakes, coatings, and shaped or randomly-shaped abrasive particles, are produced from a unique sol-gel process wherein hydroxy iron polymers are utilized to nucleate the alpha alumina transformation. An inherent advantage of the unique process disclosed is the resulting fine grained microstructure, and a surface roughness height of less than 100.0 nm, which is essential if a ceramic article such as an alpha alumina fiber is to have reasonable strength.
Type:
Grant
Filed:
July 9, 1990
Date of Patent:
February 9, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Thomas E. Wood, David M. Wilson, Harold G. Sowman
Abstract: This invention provides an optical medium and a process therefor wherein the medium exhibits third order nonlinear optical response and comprises a polymer with pendant groups having delocalized pi-electron character forming a charge transfer complex with dopant molecules. The optical medium is useful in optical devices, such as optical switches or light modulation devices as a component or as a coating. In other aspects, novel polymers and polymer complexes are disclosed.
Type:
Grant
Filed:
June 8, 1989
Date of Patent:
February 9, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Roberta E. Harelstad, Cecil V. Francis, Kenneth M. White
Abstract: A curable composition, the cure of which can be monitored optically, comprises at least one of a hydride curable silicone, an ethylenically unsaturated compound, and a cationically polymerizable monomer, and as cure monitor dibenzofulvene or derivative thereof. The cure monitor is a latent fluorophore which reacts under the cure conditions to form a UV-detectable fluorophore.The invention also provides a method for measuring degree of cure of a polymeric material which can be a coating or an article.
Type:
Grant
Filed:
November 26, 1991
Date of Patent:
January 26, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Robert J. DeVoe, Katherine A. Brown-Wensley, George V. D. Tiers
Abstract: This invention provides synthetic routes for novel single isomers of monocarbamate diols and their polymerization to provide novel polyesters, polyurethanes, polycarbonates, and the like having pendant carbamate groups on the polymer chain. Devices using some of these novel polymers which demonstrate nonlinear optical activity are also disclosed.
Type:
Grant
Filed:
September 16, 1991
Date of Patent:
November 10, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Mono O-hydroxyalkylated derivatives of 1,1-dihydroperfluorinated or 1H,1-alkylperfluorinated alcohols are prepared by reacting the alcohols with alkylene carbonates at a temperature of at least 60.degree. C. in the presence of a one- or two-part catalyst. The catalyst is a nitrogenous base, optionally in combination with a tetraalkylammonium halide. The O-hydroxyalkylated derivatives are useful non-ionic surfactants and emulsifiable compounds for fire extinguishing systems.
Type:
Grant
Filed:
June 13, 1991
Date of Patent:
October 20, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Compounds containing alpha-amidoacetyle linkages are described that are thermally labile and yield nucleophilic and azlactone products. Nucleophiles are useful as curing agents for epoxy resin sealants and adhesives and azlactones are useful in crosslinking systems for polymers.
Type:
Grant
Filed:
December 12, 1989
Date of Patent:
October 20, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Larry R. Krepski, Steven M. Heilmann, Dean M. Moren, Jerald K. Rasmussen
Abstract: Azlactone-functional Michael adducts are disclosed which are the Michael reaction products of 2-alkenyl azlactones and Michael donors selected from carbon and nitrogen nucleophiles. Reaction products which contain a plurality of azlactone groups are useful as step growth monomers in adhesives, sealants, and coatings.
Type:
Grant
Filed:
March 28, 1990
Date of Patent:
September 22, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Dean M. Moren, Steven M. Heilmann, Larry R. Krepski, Jerald K. Rasmussen
Abstract: Azlactone functional silicon containing compounds are prepared from alkenyl azlactones and SiH containing compounds in a hydrosilation reaction. The resulting compounds can be reacted with nucleophilic compounds to provide amidoacyl group containing silicon compounds. When the amidoacyl group containing silicon compounds contain ethylenic unsaturated they can be polymerized to provide polymeric networks useful as pressure sensitive adhesives release compositions, or elastomeric materials.
Type:
Grant
Filed:
June 1, 1990
Date of Patent:
September 15, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: An energy polymerizable composition comprises at least one ethylenically-unsaturated monomer, one of polyurethane precursors, and at least one epoxy monomer, and a curing agent comprising an organometallic compound, and an onium salt.
Type:
Grant
Filed:
April 24, 1990
Date of Patent:
September 15, 1992
Assignee:
Minnesosta Mining and Manufacturing Company
Inventors:
Michael C. Palazzotto, Katherine A. Brown-Wensley, Robert J. DeVoe
Abstract: A composite article having controlled void volume and mean pore size comprises:(a) polytetrafluoroethylene (PTFE) fibril matrix, and(b) insoluble, non-swellable sorptive particles enmeshed in said matrix, the ratio of non-swellable sorptive particles to PTFE is in the range of 40:1 to 1:4 by weight, the composite article having a porosity in the range of 30 to 80 percent void volume and a mean pore size in the range of 0.3 to 5 micrometers, preferably with at least 90 percent of pores having a size less than 3.6 micrometers.The article is prepared by incorporating lubricant in the precursor admixture in an amount sufficient to exceed the lubricant sorptive capacity of the particles by at least 3 weight percent and up to an amount at which the mass loses its integrity.
Type:
Grant
Filed:
May 28, 1991
Date of Patent:
September 15, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Donald F. Hagen, Craig G. Markell, William V. Balsimo, Louis A. Errede
Abstract: A polymorph of a phthalocyanine, designated M-phthalocyanine or M-metal phthalocyanine, has spectroscopic properties different from those of any of known crystalline polymorphs of phthalocyanine, the polymorph having been prepared in an environment of at most 0.1 G. In a further aspect, a process is disclosed for preparing novel organic films comprising a closed chamber physical vapor transport (PVT) in a low gravity environment.Films of novel polymorphs have a surface roughness factor in the range of greater than 1.000000 and less than 1.0000010, a density of at least 50 percent increase over any polymorph of the same molecules produced in unit gravity, and in which at least 50 weight percent of the molecules of said film have a common uniaxial orientation.
Type:
Grant
Filed:
August 20, 1990
Date of Patent:
August 18, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A curable composition, the cure of which can be monitored optically, comprises at least one of a hydride curable silicone, an ethylenically unsaturated compound, and a cationically polymerizable monomer, and as cure monitor dibenzofulvene or derivatives thereof. The cure monitor is a latent fluorophore which reacts under the cure conditions to form a UV-detectable fluorophore.The invention also provides a method for measuring degree of cure of a polymeric material which can be a coating or an article.
Type:
Grant
Filed:
June 3, 1991
Date of Patent:
June 2, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Robert J. DeVoe, Katherine A. Brown-Wensley, George V. D. Tiers
Abstract: Pressure sensitive adhesive compositions comprise one or more poly(alpha-olefin) homopolymers, copolymers, terpolymers, and tetrapolymers derived from monomers containing 6 to 10 carbon atoms and photoactive crosslinking agents. Radiation curing provides adhesive films having a superior balance of peel and shear adhesive properties. The pressure sensitive adhesive is useful in pressure sensitive adhesive tapes, in articles containing transfer adhesive films, and as the bonding material between supports in a laminated structure.
Type:
Grant
Filed:
September 6, 1989
Date of Patent:
May 12, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Gaddam N. Babu, Susan S. Christopher, Bruce C. Copley, Thomas S. Overstreet