Patents by Inventor Robert H. Tang
Robert H. Tang 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: 5882501Abstract: Describes a method of electrochemically converting amine hydrohalide, e.g., ethyleneamine hydrochloride, into free amine, e.g., free ethyleneamine, by charging an aqueous solution of amine hydrohalide to the catholyte compartment of an electrolytic cell, which contains a cathode, charging hydrogen gas to the anode compartment of the cell, which contains an anode assembly comprised of a hydrogen consuming gas diffusion anode fixedly held between a current collecting electrode and an anion exchange membrane. The catholyte and anode compartments of the cell are separated by the anion exchange membrane. An amine hydrohalide solution containing free amine is removed from the catholyte compartment.Type: GrantFiled: August 18, 1997Date of Patent: March 16, 1999Assignee: PPG Industries, Inc.Inventors: Peter C. Foller, David G. Roberts, Robert H. Tang
-
Patent number: 5811605Abstract: The dehydrochlorination of 1,1,2,3,3-pentachloropropane to produce 1,2,3,3-tetrachloropropene is conducted using aqueous alkali metal hydroxide in the substantial absence of added ethanol.The 1,2,3,3-tetrachloropropene is recovered from the reaction mixture in the substantial absence of added ether. The preferred methods of recovery are steam distillation and flash distillation.Type: GrantFiled: February 19, 1997Date of Patent: September 22, 1998Assignee: PPG Industries, Inc.Inventors: Robert H. Tang, G. V. Bindu Madhavan, Yingchao Zhang
-
Patent number: 5728771Abstract: A composition and method for providing a non-formaldehyde durable press finish to cellulosic fabrics by employing polyphosphinocarboxylic acids are disclosed. The polyphosphinocarboxylic acid is preferably polyphosphinoacrylic acid, and is optimally used in combination with phosphonoalkylpolycarboxylic acid, and, for cost effectiveness, a low-cost polycarboxylic acid such as citric acid. The catalyst for the curing reaction is preferably a phosphorus-containing acid or alkali metal salt thereof such as a mixture of sodium monophosphate and sodium hypophosphite.Type: GrantFiled: November 28, 1995Date of Patent: March 17, 1998Assignee: PPG Industries, Inc.Inventors: Robert H. Tang, William A. Williams, Jr.
-
Patent number: 5705475Abstract: A composition and method for providing a non-formaldehyde durable press finish to cellulosic fabrics by employing phosphonoalkylpolycarboxylic acids are disclosed. The phosphonoalkylpolycarboxylic acid is optimally used in combination with another polycarboxylic acid, such as polyacrylic acid, and/or, for cost effectiveness, a low-cost polycarboxylic acid such as citric acid. The catalyst for the curing reaction is optimally a phosphorus-containing acid or alkali metal salt thereof, such as a mixture of sodium monophosphate and sodium hypophosphite.Type: GrantFiled: January 16, 1996Date of Patent: January 6, 1998Assignee: PPG Industries, Inc.Inventors: Robert H. Tang, William A. Williams, Jr.
-
Patent number: 5496476Abstract: A composition and method for providing a non-formaldehyde durable press finish to cellulosic fabrics by employing phosphonoalkylpolycarboxylic acids are disclosed. The phosphonoalkylpolycarboxylic acid is optimally used in combination with another polycarboxylic acid, such as polyacrylic acid, and/or, for cost effectiveness, a low-cost polycarboxylic acid such as citric acid. The catalyst for the curing reaction is optimally a phosphorus-containing acid or alkali metal salt thereof, such as a mixture of sodium monophosphate and sodium hypophosphite.Type: GrantFiled: May 24, 1994Date of Patent: March 5, 1996Assignee: PPG Indutstries, Inc.Inventors: Robert H. Tang, William A. Williams, Jr.
-
Patent number: 5496477Abstract: A composition and method for providing a non-formaldehyde durable press finish to cellulosic fabrics by employing polyphosphinocarboxylic acids are disclosed. The polyphosphinocarboxylic acid is preferably polyphosphinoacrylic acid, and is optimally used in combination with phosphonoalkylpolycarboxylic acid, and, for cost effectiveness, a low-cost polycarboxylic acid such as citric acid. The catalyst for the curing reaction is preferably a phosphorus-containing acid or alkali metal salt thereof such as a mixture of sodium monophosphate and sodium hypophosphite.Type: GrantFiled: May 24, 1994Date of Patent: March 5, 1996Assignee: PPG Industries, Inc.Inventors: Robert H. Tang, William A. Williams, Jr.
-
Patent number: 5296627Abstract: Describes terminally ethylenically unsaturated poly(alkyleneoxy) surfactant compounds of the general formula, R--O--(R'O).sub.m --(EO).sub.n-1 --CH.sub.2 CH.sub.2 --X, wherein R is the ethylenically unsaturated hydrocarbon group, e.g., allyl, R' is the bivalent radical derived from butylene oxide, E is the bivalent ethylene radical, m and n are numbers of from 10 to 15 and 10 to 40 respectively, and X is chloride, tertiaryamino, sulfonate, sulfate, phosphate, isethionate and alkali metal salts of the anionic groups. These surfactant compounds may be used in emulsion polymerization of ethylenically unsaturated, e.g., vinyl, monomers.Type: GrantFiled: December 4, 1992Date of Patent: March 22, 1994Assignee: PPG Industries, Inc.Inventors: Robert H. Tang, Paritosh M. Chakrabarti
-
Patent number: 5231211Abstract: Di(organo) esters of pyrocarbonic acid, e.g., dialkyl pyrocarbonates, such as diethyl pyrocarbonate, are prepared by reaction of the corresponding organohaloformate with aqueous alkali metal hydroxide, e.g., sodium hydroxide, in the substantial absence of an organic solvent and in the presence of a catalytic amount of a bis[poly(oxy(C.sub.2 -C.sub.4)alkylene)] C.sub.6 -C.sub.20 aliphatic amine, e.g., coco bis(polyoxyethylene) amine.Type: GrantFiled: September 18, 1992Date of Patent: July 27, 1993Assignee: PPG Industries, Inc.Inventor: Robert H. Tang
-
Patent number: 5162475Abstract: Describes alpha-beta ethylenically unsaturated poly(alkyleneoxy) compounds that display surfactant activity and that polymerize when used in the emulsion polymerization of ethylenically unsaturated monomers, including vinyl monomers. Certain of the polymer products are useful in imparting improved hand or feel to textile fabrics.Type: GrantFiled: June 27, 1991Date of Patent: November 10, 1992Assignee: PPG Industries, Inc.Inventors: Robert H. Tang, Paritosh M. Chakrabarti, Edward J. Rish, William A. Williams
-
Patent number: 4742133Abstract: A liquid monomer composition comprising of at least one poly(allyl carbonate)-functional monomer is contacted with molecular oxygen to produce a liquid intermediate composition which is then heated to produce a polymerizable, liquid substantially gel-free composition which contains poly(allyl carbonate)-funtional prepolymer which has an allylic utilization of at least about 12 percent.Type: GrantFiled: September 24, 1985Date of Patent: May 3, 1988Assignee: PPG Industries, Inc.Inventors: Felicia Y. Tang, Robert H. Tang
-
Patent number: 4686266Abstract: Fully cured, intact, solid castings of bis(allyl carbonate) resin, e.g., diethylene glycol bis(allyl carbonate), are prepared by polymerizing the resin with between about 0.75 and about 1.50 parts, per hundred parts of resin, of a monoperoxycarbonate, e.g., tertiarybutylperoxy isopropyl carbonate. An adhesion reducing amount, e.g., between about 25 and about 75 parts, per million parts of resin, of a mold release agent is incorporated into the liquid resin monomer to avoid cracking of the casting. Use of a mold release agent is not required when the resin is prepolymerized to about 15-20 percent allylic utilization.Type: GrantFiled: May 1, 1986Date of Patent: August 11, 1987Assignee: PPG Industries, Inc.Inventor: Robert H. Tang
-
Patent number: 4613656Abstract: Fully cured, intact, solid castings of bis(allyl carbonate) resin, e.g., diethylene glycol bis(allyl carbonate), are prepared by polymerizing the resin with between about 0.75 and about 1.50 parts, per hundred parts of resin, of a monoperoxycarbonate, e.g., tertiarybutylperoxy isopropyl carbonate. An adhesion reducing amount, e.g., between about 25 and about 75 parts, per million parts of resin, of a mold release agent is incorporated into the liquid resin monomer to avoid cracking of the casting. Use of a mold release agent is not required when the resin is prepolymerized to about 15-50 percent allylic utilization.Type: GrantFiled: November 23, 1984Date of Patent: September 23, 1986Assignee: PPG Industries, Inc.Inventor: Robert H. Tang
-
Patent number: 4590008Abstract: Organic peroxydicarbonates such as bis[3-(isobutyryloxy)-2,2,4-trimethylpentyl] peroxydicarbonate are described. The peroxydicarbonates are useful as initiators for the polymerization or copolymerization of vinyl acetate and may be used in combination with the more commonly used peroxydicarbonates such as diisopropyl peroxydicarbonate.Type: GrantFiled: June 7, 1984Date of Patent: May 20, 1986Assignee: PPG Industries, Inc.Inventors: Robert H. Tang, John C. Crano
-
Patent number: 4584142Abstract: Organic peroxydicarbonates represented by the following graphic formula are described. ##STR1## In the formula, R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are each independently selected from an alkyl group containing from 1 to 4 carbon atoms. R.sub.1 and R.sub.2 and/or R.sub.3 and R.sub.4 can participate in a cycloalkyl group having from 3 to 6 carbon atoms. The peroxydicarbonates are useful as initiators for the polymerization or copolymerization of ethylenically unsaturated monomers or the cross-linking of unsaturated polyester resins. The organic peroxydicarbonates can be used in combination with commercially available peroxydicarbonates, particularly those having a longer half-life, or with peresters, diacylperoxides and azo compounds.Type: GrantFiled: November 3, 1983Date of Patent: April 22, 1986Assignee: PPG Industries, Inc.Inventors: Robert H. Tang, James A. Barter
-
Patent number: 4552682Abstract: Phenolic antioxidant compounds are added to aqueous dispersions of organic peroxide to reduce the rate of self induced homolytic decomposition of the peroxide at temperatures of from above -5.degree. C. to +20.degree. C. From about 0.1 to about 2 mole percent, basis the organic peroxide, of phenolic antioxidant is preferentially used. Among the organic peroxides described are the dialkylperoxydicarbonates. Among the phenolic antioxidants described are hindered phenols such as 2,6-di-tertiarybutyl-4-methylphenol.Type: GrantFiled: September 30, 1982Date of Patent: November 12, 1985Assignee: PPG Industries, Inc.Inventors: Donald J. Black, Robert H. Tang
-
Patent number: 4526726Abstract: Described are organic peroxycarbonates of the graphic formula: ##STR1## in which R.sub.1 is a C.sub.1 -C.sub.14 alkyl, phenyl or benzyl group, R.sub.2 and R.sub.3 are each selected from the group C.sub.1 -C.sub.4 alkyl, C.sub.5 -C.sub.7 cycloalkyl, C.sub.1 -C.sub.4 alkyl substituted C.sub.5 -.sub.7 cycloalkyl or participate in a cycloalkyl group of from 5 to 7 carbon atoms, provided that when one of R.sub.2 and R.sub.3 is a cycloalkyl group, the other is an alkyl group, A is cyano or alkoxycarbonyl, i.e., ##STR2## wherein R is a C.sub.1 -C.sub.8 alkyl or cyclohexyl group. Preferably R.sub.2 and R.sub.3 are each a C.sub.1 -C.sub.2 alkyl group or participate to form a cyclohexyl group, R.sub.1 is a C.sub.1 -C.sub.3 alkyl or phenyl and R is a C.sub.1 -C.sub.4 alkyl.The compounds can be used as initiators for the polymerization and copolymerization of ethylenically unsaturated monomers.Type: GrantFiled: September 30, 1982Date of Patent: July 2, 1985Assignee: PPG Industries, Inc.Inventor: Robert H. Tang
-
Patent number: 4522991Abstract: Organic peroxydicarbonates represented by the following graphic formula are described. ##STR1## In the formula, R and R' are each selected from an alkyl group containing from 1 to 4 carbon atoms, a cycloalkyl group of from 5 to 7 carbon atoms, a C.sub.1 -C.sub.4 alkyl substituted cycloalkyl group, or participate in a cycloalkyl group having from 5 to 7 carbon atoms, provided that when one of R and R' is cycloalkyl, the other is alkyl. The peroxydicarbonates are useful as initiators for the polymerization or copolymerization of ethylenically unsaturated monomers or the cross-linking of unsaturated polyester resins. The organic peroxydicarbonates can be used in combination with commercially available peroxydicarbonates, particularly those having a shorter half-life.Type: GrantFiled: August 20, 1984Date of Patent: June 11, 1985Assignee: PPG Industries, Inc.Inventor: Robert H. Tang
-
Patent number: 4515929Abstract: Dispersions of organic peroxide, e.g., organic peroxydicarbonates, in an aqueous medium are stabilized against homolytic peroxide decomposition at temperatures of from about -5.degree. C. to 20.degree. C. by incorporating into the dispersion, e.g., into the organic peroxide phase, from about 0.05 to about 1 mole percent, basis the organic peroxide, of diphenyl peroxydicarbonate or di(alkyl substituted) phenyl peroxydicarbonate.Type: GrantFiled: July 28, 1983Date of Patent: May 7, 1985Assignee: PPG Industries, Inc.Inventor: Robert H. Tang
-
Patent number: 4492656Abstract: Organic peroxydicarbonates represented by the following graphic formula are described. ##STR1## In the formula, R and R' are each selected from an alkyl group containing from 1 to 4 carbon atoms, a cycloalkyl group of from 5 to 7 carbon atoms, a C.sub.1 -C.sub.4 alkyl substituted cycloalkyl group, or participate in a cycloalkyl group having from 5 to 7 carbon atoms, provided that when one of R and R' is cycloalkyl, the other is alkyl. The peroxydicarbonates are useful as initiators for the polymerization or copolymerization of ethylenically unsaturated monomers or the cross-linking of unsaturated polyester resins. The organic peroxydicarbonates can be used in combination with commercially available peroxydicarbonates, particularly those having a shorter half-life.Type: GrantFiled: September 30, 1982Date of Patent: January 8, 1985Assignee: PPG Industries, Inc.Inventor: Robert H. Tang