Abstract: The present invention describes a polymer composition effective to bind, in a sequence-specific manner to a target sequence of a duplex polynucleotide, at least two different-oriented Watson/Crick base-pairs at selected positions in the target sequence. The composition includes an uncharged backbone with 5- or 6-membered cyclic backbone structures and selected bases attached to the backbone structures effective to hydrogen bond specifically with different oriented base-pairs in the target sequence. Also disclosed are subunits useful for the construction of the polymer composition. The present invention further includes methods for (i) coupling a first free or polymer-terminal subunit, and (ii) isolating, from a liquid sample, a target duplex nucleic acid fragment having a selected sequence of base-pairs.
Abstract: The invention is a rigid polyurethane foam to which a base stock lubricating oil made of at least 55 weight percent paraffinic carbons and less than 10 weight percent aromatic carbons has been added as a hydrophobic agent protecting the polyurethane foam from reacting with environmental moisture. The foam is useful for deposit in railroad spike holes or any structural member having a cavity and where moisture within or on the cavity would otherwise react with the isocyanate to produce an uncontrollable foaming mass.
Type:
Grant
Filed:
April 22, 1992
Date of Patent:
April 11, 1995
Assignee:
BASF Corporation
Inventors:
Agus Sampara, Rob Hutchings, Tom Harris, Karl Dondorff, Kerry Bowman
Abstract: The present invention provides copolymerized polycarbonates having improved flow and formability, in addition to excellent mechanical properties, heat resistance, transparency, and water resistance obtained by copolymerization of two or more aromatic dihydroxy compounds and a compound capable of reacting with those aromatic dihydroxy compounds to form carbonate linkages, characterized in that, of all the constituent repeating units derived from aromatic dihydroxy compounds, 2-40 mole % are derived from resorcin and/or substituted resorcins.
Abstract: A process for producing a (co)polycarbonate having excellent thermal resistance, hue and impact resistance and a high molecular weight, which comprises conducting a melt-polycondensation of a dihydroxy compound and a carbonic diester as monomers in the presence of a transesterification catalyst in a tank reactor, while removing a monohydroxy-compound formed by the melt-polycondensation, thereby obtaining a reaction mixture comprising a prepolymer in a molten state (the first step), cooling the molten reaction mixture obtained in the first step to solidify it (the second step), and conducting a melt-polycondensation of the reaction mixture comprising the prepolymer in a horizontal polycondensation reactor, thereby obtaining a reaction mixture comprising a high-molecular-weight (co)polycarbonate (the third step).
Abstract: A process is provided for preparing improved aqueous gelatin compositions for improved coatings, particularly light sensitive photographic coatings, wherein a viscosity increasing amount of a copolymer of an alkali metal or ammonium salt of a sulfonic acid containing polymer with an unsaturated monomer, particularly a copolymer of acrylamide and sodium-2-acrylamido-2-methylpropanesulfonate, is added to an aqueous gelatin composition at a point immediately before any point which requires a high viscosity after and a low viscosity before the addition.
Abstract: Liquid-melt aliphatic dicarboxylic acids tend to undergo undesirable discoloration during prolonged storage. The discoloration can be avoided by an addition of 0.1 to 3.0% by weight of a primary amine.
Abstract: The present invention is directed to an isocyanate reactive mixture and the flexible polyurethane foam produced therefrom. The reactive mixture contains specific filled polyols, water, a catalyst for the reaction between an isocyanate group and a hydroxyl group, and a specific N-hydroxyalkyl quaternary ammonium salt. The isocyanate used is toluene diisocyanate.
Abstract: A process for producing a lactic acid-based copolyester by the ring-opening copolymerization and transesterification of a lactide (A) with an aromatic polyester (B) and/or an aliphatic polyester (C) in the presence of a ring-opening polymerization catalyst (D), and a packaging material comprising the lactic acid-based copolyester obtained by the process are disclosed. According to the present invention, a lactic acid-based degradable copolyester which has a sufficiently high molecular weight and satisfactory toughness and also has suitable rigidity, pliability, and transparency according to applications can be produced. Further, a general-purpose packaging material, e.g., a sheet or film, which comprises the lactic acid-based copolyester produced by the process and is excellent in formability, degradability, and transparency can also be produced.
Abstract: Sub-micron features are defined photo-lithographically by combining phase-shifting techniques with conventional photo lithographic techniques. In a first step, phase-shifting edges are defined in a photoresist layer. Dark-bands develop at the phase-shifting edges due to wavefront interference of an illuminating radiation in a subsequent exposure step. Development leaves behind sub-micron sections of photoresist which were covered by the dark-band regions. The dark-band sections are hardened and overcoated with a new layer of photoresist. A second pattern is projected onto the second layer of photoresist using conventional techniques. The second pattern is developed so as to create features having dimensions reduced by parts of the dark-band sections previously developed.
Type:
Grant
Filed:
September 29, 1992
Date of Patent:
April 4, 1995
Assignees:
Sharp Kabushiki Kaisha, Sharp Microelectronics Technology, Inc.
Abstract: Disclosed are a foamable resin composition which comprises a copolymer with a weight-average molecular weight of 150,000-350,000 produced by copolymerization of a monomer mixture of 55-85% by weight of styrene and 45-15% by weight of a methacrylic acid ester represented by general formula (I)CH.sub.2 .dbd.C(CH.sub.3)COOR (I)(wherein R represents a C.sub.
Type:
Grant
Filed:
August 18, 1993
Date of Patent:
April 4, 1995
Assignees:
Hitachi Chemical Co., Ltd., Foseco International Ltd.
Inventors:
Yoshiyuki Kato, Hideaki Shibata, William Simmons, Nigel K. Graham
Abstract: A corrosion-resistant polyurethane coating for application directly to a face as a self-priming topcoat comprising major amount of a polyurethane binder and minor amount of a combination of pigments consisting essentially of an aluminum phosphate, zinc salts of benzoic acids, and an alkaline earth metal phosphate such as zinc-barium phosphate. In addition, the coating contains up to about 30 parts by weight of a titanium dioxide pigment, up to about 2.0 parts by weight of an oil soluble surface active agent and up to about 50 parts by weight of at least one organic solvent.
Type:
Grant
Filed:
March 7, 1994
Date of Patent:
April 4, 1995
Assignee:
The United States of America as represented by the Secretary of the Navy
Inventors:
Charles R. Hegedus, Donald J. Hirst, Anthony T. Eng
Abstract: The thermooxidative stability and thermomechanical properties of advanced composites which use high performance resin matrices such as polyimides and high strength carbon fibers may be improved by sizing the carbon fibers with uncapped or capped linear polyamideimides.The uncapped linear polyamideimides useful as carbon fiber sizings generally contain repeating units having the general formula: ##STR1## Wherein R.sub.2 =a trivalent organic radical and generally benzenetriyl;R.sub.3 =a divalent organic radical; andn=an integer sufficiently large to provide a strong, tough coating.Useful capped, linear polyamideimide oligomers may be formed by including end caps with an unsaturated functionality (Y) containing a residue selected from the group consisting of: ##STR2## wherein R.sub.1 =lower alkyl, lower alkoxy, aryl, aryloxy, substituted alkyl, substituted aryl, halogen, or mixtures thereof;j=0, 1, or 2;i=1 or 2;G=--CH.sub.2 --, --O--, --S--, --SO.sub.2 --, --SO--, --CO--, --CHR--, or --CR.sub.
Type:
Grant
Filed:
June 21, 1993
Date of Patent:
April 4, 1995
Assignee:
The Boeing Company
Inventors:
Hyman R. Lubowitz, Clyde H. Sheppard, Ronald R. Stephenson
Abstract: The description relates to a physically drying water-based coating agent. It contains water, pigments, neutralizing agents, conventional additives, small proportions of solvents and a binder mixture consisting ofA) 10 to 90 wt. % polyurethanes with carbonate groupings and a glass transition temperature of <0.degree. C. based on reaction products of polyisocyanates with polyhydroxyl compounds, with a content of polyhydroxy polycarbonates andB) 90 to 10 wt. % of reaction products of carboxy-functional polycondensates and .alpha.,.beta.-olefinically unsaturated monomers with a glass transition temperature of >0.degree. C. in the form of an aqueous dispersion.The coating agent is particularly suitable for manufacturing lacquers for repairs in the motor vehicle sector.
Type:
Grant
Filed:
April 19, 1993
Date of Patent:
March 28, 1995
Assignee:
Herberts Gesellschaft mit beschrankter Haftung
Inventors:
Thomas Brock, Hans-Peter Patzschke, Fritz Sadowski
Abstract: A copolymeric polycarbonate containing repeating constituent units having formula [I] below and repeating constituent units having formula [II] below in a molar ratio of from 98:2 to 40:60. ##STR1## The above-described copolymeric polycarbonates have excellent resistance to chemicals, heat resistance and flame retardancy without compromising the impact resistance and good hues intrinsic to polycarbonates.
Abstract: Binder systems suitable for electrocoating and consisting of a base resin A which carries groups which can be protonated with acids or cationic quaternary groups and, if desired, hydroxyl or thiol groups, a crosslinking component B which carries at least two blocked isocyanate groups per molecule and an organic iron compound C which is partially or completely soluble in water, as a catalyst for the thermal crosslinking of components A and B, and if desired, an additive D which increases the catalytic activity of C, are used to prepare dispersions which are used for electrocoating.
Type:
Grant
Filed:
March 8, 1993
Date of Patent:
March 28, 1995
Assignee:
BASF Lacke & Farben AG
Inventors:
Klaus Huemke, Gerhard Hoffmann, Dieter Faul, Rainer Blum
Abstract: A semiconductive conjugated copolymer comprises at least two chemically different monomer units which, when existing in their individual homopolymer forms, have different semiconductor bandgaps. The proportion of said at least two chemically different monomer units in the copolymer is selected to control the semiconductor bandgap of the copolymer so as to control the optical properties of the copolymer. The copolymer is formed in a manner enabling it to be laid down as a film without substantially affecting the luminescent characteristics of the copolymer and is stable at operational temperature.The semiconductor bandgap may be spatially modulated so as to increase the quantum efficiency of the copolymer when excited to luminesce, to select the wavelength of radiation omitted during luminescence or to select the refractive index of the copolymer.
Type:
Grant
Filed:
August 22, 1991
Date of Patent:
March 28, 1995
Assignee:
Cambridge Display Technology Limited
Inventors:
Andrew Holmes, Donal D. Bradley, Richard H. Friend, Arno Kraft, Paul Burn, Adam Brown
Abstract: Foamed polyurethanes substantially free from non-uniform density distribution are obtained by dispersing an inert gas with mechanical stirring into a foamed polyurethane-forming composition containing substantially no blowing agent and comprising (1) an organic polyisocyanate component, (2) a polyol component comprising a high molecular weight polyol (A1) and a low molecular weight polyol (A2), (3) a dehydrating agent (B) and optionally organic microballoons, and curing the resulting composition containing therein the inert gas substantially homogeneously distributed. Foamed polyurethanes thus obtained are lightweight and of reduced warpage after processing and are suitable for model materials.
Abstract: The invention relates to a two-stage process for the production of thermoplastic, solvent-free lightly branched polycarbonates in the melt using ammonium and/or phosphonium catalysts in the first stage and alkali metal and/or alkaline earth metal catalysts in the second stage.
Type:
Grant
Filed:
April 7, 1994
Date of Patent:
March 21, 1995
Assignee:
Bayer Aktiengesellschaft
Inventors:
Steffen Kuhling, Hermann Kauth, Wolfgang Alewelt
Abstract: The invention relates to a method of preparing a compound of formula 1 ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 correspond to H, a branched or non-branched, optionally substituted alkyl group, or an optionally substituted aryl group, suitable as a chain stopper in the preparation of an aromatic polycarbonate, by reaction of a compound of formula 2 ##STR2## wherein R.sub.1, R.sub.2 and R.sub.3 have the meanings described hereinbefore, with phosgene, comprising the continuous supply of the compound of formula 2 and phosgene to a solution of phosgene in a solvent, the temperature being kept at a value between 0.degree. and 15.degree. C. and the pH being kept at a value between 1 and 6.
Type:
Grant
Filed:
October 26, 1993
Date of Patent:
March 21, 1995
Assignee:
General Electric Company
Inventors:
Henricus H. M. van Hout, Christianus J. J. Maas, Laurus van der Wekke, Martin H. Oyevaar
Abstract: An amine terminated random copolymer containing ethylene oxy/propylene oxy segments may be reacted with hexamethylene diamine and adipic acid monomers to make improved poly(etheramide) segmented block copolymers. Ordinarily, poly(propylene glycol) diamines tend to phase separate under these conditions and polyamide-6,6 could not be so modified. The resultant poly(etheramide) segmented block copolymer has improved impact performance, reduced modulus and lower glass transition as contrasted with the non-modified polyamide-6,6.