Abstract: A method for reducing corrosion in a diolefin extractive distillation process comprising preventing the formation of ammonium carbonate by promoting the formation of a carbonate salt that does not dissociate in the ammonium carbonate dissociation temperature range of that extractive distillation process.
Type:
Grant
Filed:
June 9, 2008
Date of Patent:
May 18, 2010
Assignee:
Equistar Chemicals, LP
Inventors:
Joseph P. Bridges, Robert J. Haynal, Allen David Hood, Jr., Solon B. Williams
Abstract: In accordance with the invention, propylene oxide is formed by reaction of propylene and hydrogen peroxide or by reaction of propylene, oxygen and hydrogen in methanol solvent, methanol and methyl formate are separated from propylene oxide by extractive distillation wherein the aqueous bottoms from methanol recovery distillation is used as extractive distillation solvent after first having been neutralized.
Abstract: High purity tertiary butyl alcohol is obtained from mixtures comprised of tertiary butyl alcohol and tertiary butyl acetate by extractive distillation using a hydrocarbon extractive solvent such as decane.
Abstract: Elastomers exhibiting decreased demold times and improved green strength are prepared by reacting a di- or polyisocyanate with a monodisperse polyoxypropylene diol having ultra-low unsaturation, and preferably prepared by the double metal cyanide.t-butyl alcohol catalyzed polymerization of propylene oxide. Further improved demold times and elevated elastomer physical properties are made possible by the use of multidisperse polyoxyalkylene polyether polyol blends having an overall unsaturation of less than 0.010 meq/g and a polydispersity of about 1.4 or greater.
Type:
Grant
Filed:
May 27, 1997
Date of Patent:
December 15, 1998
Assignee:
ARCO Chemical Technology, L.P.
Inventors:
Gary L. Allen, Nigel Barksby, Stephen D. Seneker, Usama E. Younes
Abstract: An improved process for cell opening of cellular polyurethane molded foam using timed partial pressure release (TPPR) reduces pinch deformation and contour lines by releasing the internal mold pressure in a curing cellular molded polyurethane foam product in a controlled manner which allows gas to escape from the mold, but which prohibits relative movement of the mold sealing surfaces by more than an imperceptible amount.
Abstract: Substantially transition metal-free polyoxyalkylene polyethers may be prepared by double metal cyanide complex-catalyzed oxyalkylation of a suitable hydric oxyalkylation initiator molecule by employing 15 ppm or less of a double metal cyanide complex oxyalkylation catalyst having a propylene oxide polymerization rate greater than 5 g propylene oxide/minute. The induction periods associated with oxyalkylation employing double metal cyanide complex catalysts may be reduced by preparing preactivated master batches and by increasing the oxyalkylation reactor temperature during at least the induction period.
Abstract: Polymer polyols and polymer-modified polyols having substantially no transition metal content in the polyol continuous phase may be prepared from encapsulative double metal cyanide complex-catalyzed polyoxyalkylene polyether base polyols without substantial removal of double metal cyanide complex catalyst residues from the base polyol and subsequent in situ polymerization of one or more polymerizable monomers.
Type:
Grant
Filed:
November 30, 1995
Date of Patent:
November 18, 1997
Assignee:
ARCO Chemical Technology, L.P.
Inventors:
Donald W. Simroth, Xinhua Zhou, Charles V. Rose
Abstract: Elastomers exhibiting decreased demold times and improved green strength are prepared by reacting a di- or polyisocyanate with a monodisperse polyoxypropylene diol having ultra-low unsaturation, and preferably prepared by the double metal cyanide.t-butyl alcohol catalyzed polymerization of propylene oxide. Further improved demold times and elevated elastomer physical properties are made possible by the use of multidisperse polyoxyalkylene polyether polyol blends having an overall unsaturation of less than 0.010 meq/g and a polydispersity of about 1.4 or greater.
Type:
Grant
Filed:
June 15, 1995
Date of Patent:
September 23, 1997
Assignee:
Arco Chemical Technology, L.P.
Inventors:
Gary L. Allen, Nigel Barksby, Stephen D. Seneker, Usama E. Younes
Abstract: Cold molded flexible polyurethane foams may be prepared from low primary hydroxyl Polyoxyalkylene polyols when polyoxyalkylene polyols having an unsaturation of 0.02 meq/g or less provide the substantial portion of the polyol component.
Type:
Grant
Filed:
December 21, 1995
Date of Patent:
September 16, 1997
Assignee:
ARCO Chemical Technology, L.P.
Inventors:
Mark R. Kinkelaar, Frank E. Critchfield, James L. Lambach
Abstract: Polyoxyalkylene polyether polyols suitable for preparation of flexible polyurethane foams are prepared by oxyalkylating an aqueous solution of one or more polyhydric, hydroxyl-functional solid initiators under conditions where both water as well as initiator are oxyalkylated. The polyols have calculated functionalities of between about 2.2 and 4.0 and hydroxyl numbers in the range of 10 to 180. The polyols may be used to prepare soft, high resiliency polyurethane flexible foams at low isocyanate indexes.
Type:
Grant
Filed:
October 21, 1996
Date of Patent:
July 29, 1997
Assignee:
ARCO Chemical Technology, L.P.
Inventors:
Stanley L. Hager, James E. Knight, Gregory F. Helma, Ben J. Argento
Abstract: High resilience polyurethane foams exhibiting little or no shrinkage may be prepared from low unsaturation double metal cyanide catalyzed polyoxyalkylene polyols in amounts greater than 20 weight percent of the total polyol component, when low unsaturation poly(oxypropylene/oxyethylene) random polyols having less than 35 weight percent of an all polyoxypropylene block catalyzed by double metal cyanide catalysts and one or more external random polyoxypropylene/polyoxyethylene blocks each containing 2 weight percent or more oxyethylene moieties, and an unsaturation of less than 0.02 meq/g are employed.
Abstract: A process for the manufacture of re-bonded foam products is disclosed. The process comprises mixing a liquid comprising polyol with a liquid comprising polyisocyanate in the presence of small pieces of foam, consolidating the mixture, and causing the polyol and polyisocyanate to react and bond the coated pieces together.
Abstract: High resilience polyurethane foams exhibiting little or no shrinkage may be prepared from low unsaturation double metal cyanide catalyzed polyoxyalkylene polyols in amounts greater than 20 weight percent of the total polyol component, when low unsaturation poly(oxypropylene/oxyethylene) random polyols having less than 35 weight percent of an all polyoxypropylene block catalyzed by double metal cyanide catalysts and one or more external random polyoxypropylene/polyoxyethylene blocks each containing 2 weight percent or more oxyethylene moieties, and an unsaturation of less than 0.02 meq/g are employed.
Abstract: High quality, consistent polyurethane froth foams, both filled and unfilled, are prepared by directing polyol, isocyanate, and optionally other polyurethane-forming ingredients to a high pressure mix head prior to introducing the mixture to a froth foaming head. Changes in stoichiometry may be made rapidly without shut-down. An in-line blender incorporated filler into the polyol stream minimizing density differentials normally encountered in the holding tank, maintaining low and reproducible viscosity, and allowing for greater amounts of filler than otherwise possible.
Abstract: Polyoxyalkylene polyether polyols suitable for preparation of flexible polyurethane foams are prepared by oxyalkylating an aqueous solution of one or more polyhydric, hydroxyl-functional solid initiators under conditions where both water as well as initiator are oxyalkylated. The polyols have calculated functionalities of between about 2.2 and 4.0 and hydroxyl numbers in the range of 10 to 180. The polyols may be used to prepare soft, high resiliency polyurethane flexible foams at low isocyanate indexes.
Type:
Grant
Filed:
July 26, 1995
Date of Patent:
January 21, 1997
Assignee:
ARCO Chemical Technology, L.P.
Inventors:
Stanley L. Hager, James E. Knight, Gregory F. Helma, Ben J. Argento
Abstract: Aqueous polyurethane dispersions prepared from chain extended polyurethane prepolymers which are the reaction product of a di- or polyisocyanate, a polyol component containing, in major part, a polyoxypropylene diol having an unsaturation of 0.020 meq/g or less, and a reactive dispersing aid, are suitable for preparing polyurethane films with greater softness and elasticity than similar films prepared from PTMEG, and greater tensile strength and elasticity than polyoxypropylene diols having conventional levels of unsaturation.
Abstract: High resilience polyurethane foams having improved wet set properties are obtained by reacting an isocyanate with a polyol component consisting of a polyoxyalkylene polyol with a functionality of 6 or more and a polymer polyol whose base polyol is a polyoxyalkylene polyol with a functionality of 6 or more, both polyols having oxyethylene caps in amounts of from 12 percent to about 30 percent based on the weights of the respective polyols, in the presence of an amine catalyst system. The resulting polyurethane foams are eminently suitable for seating cushions used in tropical or subtropical environments, may be prepared by a cold molding process, and may be used without an elevated temperature post cure.
Type:
Grant
Filed:
March 24, 1995
Date of Patent:
August 27, 1996
Assignee:
Arco Chemical Technology, L.P.
Inventors:
Mark R. Kinkelaar, Keith D. Cavender, James L. Lambach, Robert D. Brasington, Frank E. Critchfield
Abstract: The addition of minor quantities of a hydroxyl-functional polyoxyalkylene monol to a PTMEG-derived isocyanate-terminated prepolymer during prepolymer preparation enables the preparation of glycol extended polyurethane elastomers which exhibit improved physical properties, particularly elongation, tensile strength, and tear strength, without significantly affecting elastomer hardness.
Abstract: A flexible polyurethane foam formulation comprising a first polyol, a second polyol, an unhindered primary diamine or its corresponding carbamate, a diol, water, at least one catalyst, a foam stabilizer and isocyanate is disclosed. No auxiliary blowing agent is required. The resulting soft foams have densities of less than about 2 pcf and 25% IFD values of less than about 10 pounds/50 sq. inches.
Type:
Grant
Filed:
September 23, 1994
Date of Patent:
March 19, 1996
Assignee:
ARCO Chemical Technology, L.P.
Inventors:
Otis M. Baker, Jr., Frank E. Critchfeld, Paul M. Westfall
Abstract: The present invention provides polymer polyols and a method for preparing polymer polyols which have (1) exceptional dispersion stability, especially at high styrene contents, and (2) substantially smaller particle sizes than polymer polyols having equivalent viscosity. In a preferred embodiment of the present invention, a first reaction product is obtained by feeding the following materials to a first continuous reactor in the presence of a free radical initiator or catalyst: (a) less than about 50 wt. % of a total monomer proportion or monomer mixture, preferably comprising styrene/acrylonitrile at a ratio preferably greater than about 50/50 wt. %; (b) at least about 50 wt. % of a total base polyol proportion; (c) a majority of a precursor stabilizer; and, (d) a polymer control agent (PCA).
Type:
Grant
Filed:
June 10, 1994
Date of Patent:
March 5, 1996
Assignee:
ARCO Chemical Technology, L.P.
Inventors:
Frank E. Critchfield, Donald W. Simroth, Stuart L. Watson