Classifications

• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
  • C23F11/00—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
  • C23F11/08—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
  • C23F11/10—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids using organic inhibitors
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F22/00—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals each having only one carbon-to-carbon double bond, and at least one being terminated by a carboxyl radical and containing at least one other carboxyl radical in the molecule; Salts, anhydrides, esters, amides, imides or nitriles thereof
  • C08F22/36—Amides or imides
  • C08F22/40—Imides, e.g. cyclic imides
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
  • C23F11/00—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
  • C23F11/08—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
  • C23F11/10—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids using organic inhibitors
  • C23F11/173—Macromolecular compounds

Definitions

• the present invention relates to a process for inhibiting corrosion of metallic components in contact with aqueous and non-aqueous systems. More particularly, the invention is directed to introducing oligomeric and polymeric compositions as fluid additives in aqueous systems that are effective corrosion inhibitors over a wide range of pH and render metals passive to repeated attack by oxidants and oxidizing biocides. In addition, the invention relates to a process for applying anti-corrosive coatings to metallic components.
• Corrosion may be defined as the gradual weight loss of a metallic component through some chemical process or series of chemical reactions.
• Metals in contact with aqueous systems such as sea water, fresh water and brackish water and exposed to oxidants contained therein such as chlorine, acid, bleach, caustic and dissolved oxygen are prone to corrosion.
• Metal alloys using more corrosion resistant metals e.g. Ti, Cr, Ni are one means of improving corrosion resistance.
• such alloys are costly, difficult to process and manufacture, and experience problems with corrosion at joints, welds, and under repeated exposure to corrosive agents.
• Inorganic compositions such as chromates, phosphates or zinc compositions and organic compositions such as tolyltriazole (TTA) and benzotriazole (BZT) are corrosion inhibitors applied to metals or added to fluids in contact with metallic components which inhibit or slow down the rate of metal corrosion.
• Azoles for example, are film forming compositions that adsorb to metallic surfaces and provide a barrier to contact with an aqueous system.
• the effectiveness of a particular composition is usually a trade off of its anti-corrosion properties as compared to its inherent limitations such as cost, long term performance and environmental impact. Since metal corrosion occurs under a variety of environmental conditions, specific inhibitor compositions have been developed to provide corrosion resistance for specific situations.
• TTA tolyltriazole
• BZT benzotriazole
• TTA Triazoles and oxidizing biocides
• problems associated with combining triazoles and oxidizing biocides in aqueous systems include by-products that are less effective corrosion inhibitors, by products which are volatile and that have objectionable odors and halogen containing by products that are toxic to the environment if released from the aqueous system.
• the decomposition product of TTA may be more toxic than TTA, which itself is toxic to fish populations.
• the decomposition product of TTA is believed to be an N-chlorinated compound, which is relatively volatile and susceptible to removal by stripping in the cooling tower, further reducing the levels of corrosion inhibitor and oxidizing biocide in the system.
• U.S. Pat. No. 4,282,007 discloses a corrosion inhibiting additive for a fuel composition, which is the reaction product of a C 15 -C 30 hydrocarbyl succinic acid anhydride and aminotriazole.
• a corrosion inhibiting additive for a fuel composition which is the reaction product of a C 15 -C 30 hydrocarbyl succinic acid anhydride and aminotriazole.
• such fuels contain acidic contaminants from alcohols and the additives are only effective at inhibiting corrosion of metal surfaces exposed to acidic conditions. Accordingly, it would be desirable to provide alternative methods of inhibiting metallic corrosion in aqueous systems that incorporate corrosion inhibitors that are effective over a wide range of pH, that are resistant to oxidizing biocides and that have minimal environmental impact.
• the inventors recognized a need to provide corrosion inhibiting compositions having substantive film forming ability that are effective over a wide pH range in aqueous or non-aqueous systems, that are resistant to oxidizing biocides and that can withstand repeated and prolonged chemical attack by corrosive agents such as chlorine.
• the inventors discovered polymeric corrosion inhibiting compositions that are products of reactions between anhydrides and heterocycles which are surprisingly effective copper corrosion inhibitors and remain substantive on metallic surfaces over a wide pH range in aqueous and non-aqueous systems, are resistant to oxidizing biocides, and are substantially impervious to repeated or prolonged exposure to corrosive agents.
• the present invention provides a process for inhibiting corrosion of metallic components in contact with an aqueous system comprising the step of adding to the system an effective amount of one or more polymers comprising at least one repeating unit selected from a functionalized imide component of Formula Ia, a functionalized amide component of Formula Ib and combinations of Formulas Ia and Ib:
• n is 0 or 1;
• R and R 1 are independently selected from hydrogen, methyl, and C 2 -C 4 alkyl; a heterocycle which comprises unsaturated or aromatic heterocycles having one or more hetero atoms selected from N, O, S and combinations thereof, the heterocycle chemically bonded to a nitrogen atom of Formula 1a or 1b via a hetero atom which is part of the heterocycle or a carbon atom of the heterocycle;
• R 3 is selected from hydrogen, methyl, ethyl, C 3 -C 18 branched and straight chain, alkyl and alkenyl groups; and
• R 4 is selected from H, CH 3 , C 2 H 5 , C 6 H 5 and C 3 -C 18 branched or straight chain alkyl and alkenyl groups.
• the present invention provides a process for inhibiting corrosion of metallic components in contact with an aqueous system comprising the step of adding to the system an effective amount of corrosion inhibiting polymer comprising:
• ethylenically unsaturated monomer component selected from maleic anhydride, itaconic anhydride, cyclohex-4-enyl tetrahydrophthalic anhydride, and monomers of Formula II:
• R 5 is selected from hydrogen, phenyl, methyl, ethyl, C 3 -C 18 branched and straight chain alkyl and alkenyl groups
• R 6 is independently selected from hydrogen, methyl, ethyl, phenyl, C 3 -C 18 branched and straight chain alkyl and alkenyl groups, OR 8 and CH 2 OR 8 groups wherein R 8 is acetate, glycidyl, methyl, ethyl, C 3 -C 18 branched and straight chain alkyl and alkenyl groups, and groups having the formula [CH 2 CH(R a )O] m R b wherein R a is hydrogen, methyl, ethyl, and phenyl, m is an integer from 1-20 and R b is independently hydrogen, methyl, ethyl, phenyl and benzyl; and R 7 is independently selected from H, CH 3 , C 2 H 5 , CN, a COR 9
• [0015] optionally one or more end groups selected from initiator fragments, chain transfer fragments, solvent fragments and combinations thereof.
• the present invention provides a process for inhibiting corrosion of metallic components in contact with an aqueous system comprising the step of adding to the system an effective amount of corrosion inhibiting polymer of formula III:
• A is an optional end group component selected from initiator fragments, chain transfer fragments, solvent fragments and combinations thereof; wherein B is a functionalized imide component of Formula Ia, a functionalized amide component of Formula Ib and combinations of Ia and Ib; wherein C is an ethylenically unsaturated monomer component selected from maleic anhydride, itaconic anhydride, cyclohex-4-enyl tetrahydrophthalic anhydride, and monomers of Formula II; and wherein x, y, z are integers values chosen such that (y+z)/x is greater than 2.
• the present invention also provides a process for inhibiting corrosion of metallic components in contact with an aqueous system comprising the step of adding to the system an effective amount of one or more polymers of Formula III:
• A is an end group component selected from initiator fragments, chain transfer fragments, solvent fragments and combinations thereof; wherein B is a functionalized imide component of Formula Ia, a functionalized amide component of Formula Ib and combinations of Ia and Ib; wherein C is an ethylenically unsaturated monomer component selected from maleic anhydride, itaconic anhydride, cyclohex-4-enyl tetrahydrophthalic anhydride, and monomers of Formula II; and wherein x, y, z are integers values chosen such that (y+z)/x is greater than 2.
• the present invention also provides a process for inhibiting corrosion of metallic components in contact with an aqueous system comprising the step of adding to the system an effective amount of one or more polymers comprising:
• the present invention also provides a process for inhibiting corrosion of metallic components in contact with an aqueous system comprising the step of adding to the system an effective amount of one or more polymers of Formula IV:
• A is an end group selected from initiators fragments, chain transfer fragments, solvent fragments and combinations thereof; wherein B is a functionalized imide component of Formula Ia selected from succinimide, glutarimide and combinations thereof; wherein B′ includes at least one unit selected from a functionalized imide component or a functionalized amide component selected from succinimide, glutarimide and combinations thereof, wherein the nitrogen atom of each component of B′ is chemically bonded to a group selected from C 1 -C 18 branched or straight chain alkyl, C 1 -C 18 alkyl or alkenyl substituted aryl, which is in turn chemically bonded to a pendant functional group selected from an amine group, amide group, carboxylic acid group, alcohol group or a group having the formula [CH 2 CH(R a )O] m R b wherein R a is hydrogen, methyl, ethyl, and phenyl, m is an integer from 2-20 and R b is independently hydrogen
• the present invention also provides a process for inhibiting corrosion of metallic components in contact with an aqueous system comprising the step of adding to the system an effective amount of a corrosion inhibiting formulation including one or more corrosion inhibiting polymer compositions and one or more additives selected from the group consisting of biocidal compositions, corrosion inhibiting compositions different from those of the present invention, scale inhibiting compositions, dispersants, defoamers, inert tracers and combinations thereof.
• the present invention provides a process for inhibiting corrosion of metallic components used in the manufacture of equipment associated with aqueous and non-aqueous systems that require corrosion protection.
• Aqueous system refers to any system containing metallic components which contain or are in contact with aqueous fluids on a periodic or continuous basis.
• aqueous fluids refers to fluids containing 5 weight percent or more water and includes water-based fluids.
• Water based fluids refer to fluids containing a minimum of 40 percent by weight water, the remainder being suspended and/or dissolved solids and compounds that are soluble in water.
• Non-aqueous system refers to any system containing metallic components which contain or are in contact with non-aqueous fluids on a periodic or continuous basis. Non-aqueous fluids may be miscible or immiscible in water.
• Typical aqueous systems include, for example, recirculating cooling units, open recirculating cooling units that utilize evaporation as a source of cooling, closed loop cooling units, heat exchanger units, reactors, equipment used for storing and handling liquids, boilers and related steam generating units, radiators, flash evaporating units, refrigeration units, reverse osmosis equipment, gas scrubbing units, blast furnaces, paper and pulp processing equipment, sugar evaporating units, steam power plants, geothermal units, nuclear cooling units, water treatment units, food and beverage processing equipment, pool recirculating units, mining circuits, closed loop heating units, machining fluids used in operations such as for example drilling, boring, milling, reaming, drawing, broaching, turning, cutting, sewing, grinding, thread cutting, shaping, spinning and rolling, hydraulic fluids, cooling fluids, oil production units and drilling fluids.
• machining fluids used in operations such as for example drilling, boring, milling, reaming, drawing, broaching, turning, cutting, sewing, grinding, thread cutting,
• aqueous fluids include fresh water, brackish water, sea water, waste water, mixtures of water and salts (known as brines), mixtures of water and alcohol such as methanol, ethanol and ethylene glycol, mixtures of water and acids such as mineral acids, mixtures of water and bases such as caustic and combinations thereof.
• Aqueous systems treated using the compositions of this invention may contain dissolved oxygen or may contain no oxygen.
• the aqueous systems may contain other dissolved gases such as, for example, carbon dioxide, ammonia and hydrogen sulfide.
• oligomer refers to compositions produced by the polymerization of one or more monomer units wherein the number of monomer units incorporated in the oligomer are between 2 and about 10.
• Polymer refers to compositions produced by the polymerization of one or more monomer units with no restriction on the number of types of monomer units incorporated in the polymer.
• Co-polymer refers to compositions produced by the polymerization of two different monomer units with no restriction on the number of either monomer units incorporated in the co-polymer.
• the metallic components in contact with the aqueous system are processed from any metal for which corrosion and/or scaling can be prevented.
• metals requiring corrosion protection are copper, copper alloys, aluminum, aluminum alloys, ferrous metals such as iron, steels such as low carbon steel, chromium steel and stainless steel, iron alloys and combinations thereof.
• aqueous systems such as, for example, uniform corrosion over the entire metal surface and localized corrosion such as pitting and crevice forming. Often, control of localized corrosion may be the critical factor in prolonging the useful life of the metal components in contact with the aqueous system.
• Aqueous systems containing significant concentrations (also referred to as “levels”) of anions such as chloride and sulfate are prone to both uniform and localized corrosion. These anions are often present in the aqueous fluids used in the system. Uniform and localized corrosion often result in the failure of the metallic components requiring replacement or extensive repairs and maintenance, both shutting down operation of the aqueous system. Therefore, the present invention provides polymeric compositions for inhibiting corrosion in aqueous systems.
• the corrosion resistant polymer compositions usefully employed in the present invention are substantially resistant or impervious to oxidizing biocides including for example oxidants such as oxygen, ozone and hydrogen peroxide, halogens such as chlorine, bromine, and iodine, combinations of oxidants such as NaOCl and alkali salts of Group VII (Group 17 according to the nomenclature of the International Union of Pure and Applied Chemists) elements, organic compounds such as hydantinoids, cyanuric acid derivatives, substituted cyanuric acid derivatives such as chloro cyanuric acid, alkali and alkaline earth salts of cyanuric acid and cyanuric acid derivatives, and combinations thereof.
• oxidants such as oxygen, ozone and hydrogen peroxide
• halogens such as chlorine, bromine, and iodine
• combinations of oxidants such as NaOCl and alkali salts of Group VII (Group 17 according to the nomenclature of the International Union of Pure and Applied
• the anti-corrosive compositions are substantially resistant or impervious to repeated and prolonged exposure to corrosive agents including for example chlorine, bromine, and iodine; hypochlorite and its alkali metal salts such as sodium hypochlorite; hypochloric acid; chlorous acid; mineral acids such as hydrochloric acid, sulfuric acid and phosphoric acid; perchloric acid, basic compounds such as lye, caustics, bleaches, and ammonia; reducing agents such as sulfides, sulfites and alkali metal sulfides; and combinations thereof.
• corrosive agents including for example chlorine, bromine, and iodine; hypochlorite and its alkali metal salts such as sodium hypochlorite; hypochloric acid; chlorous acid; mineral acids such as hydrochloric acid, sulfuric acid and phosphoric acid; perchloric acid, basic compounds such as lye, caustics, bleaches, and ammonia; reducing agents such
• the corrosion inhibiting compositions of the present invention are effective in highly acidic or basic aqueous systems, namely, at pH between 0.5 and 14. It is preferred that the corrosion inhibiting compositions are added to the aqueous systems at pH between 6 and 10.
• All polymers and corrosion inhibiting polymer compositions usefully employed in the present invention include at least one repeating unit selected from a functionalized imide component having Formula Ia, a functionalized amide component having Formulas Ib and combinations of Ia and Ib:
• n is 0.
• R and R 1 are hydrogen.
• R 3 is selected from C 3 -C 18 branched and straight chain alkyl groups.
• R 4 is selected from C 3 -C 18 branched and straight chain alkyl groups.
• Suitable heterocycles usefully employed in accordance with the invention include for example 5 to 7-membered heterocycles having some degree of unsaturation, aromatic heterocycles having at least one hetero atom selected from N, O or S atoms and combinations thereof.
• the heterocycle is chemically bonded to a nitrogen atom of the imide or amide component via a hetero atom which is part of the heterocycle or a carbon atom of the heterocycle.
• suitable heterocycles include for example 5 to 7-membered heterocycles that are fused together to form larger 9 to 14-membered heterocycles having more than one type or combination of N, O or S atoms, isomers of such heterocycles and combinations thereof.
• Preferred heterocyclic groups include for example imidazole, triazole, thiophene, pyrrole, oxazole, azoles, indazoles thiazoles and their respective isomers such as thiazol-4-yl, thiazol-3-yl, and thiazol-2-yl, substituted thiazoles and their respective isomers such as 2-amino thiazol-4-yl, pyrazole, tetrazole, pyridine, pyridazine, pyrimidine, pyrazine, indazoles, triazoles and their respective isomers such as 1, 2, 3-triazole, 1,2,4-triazole, and combinations thereof.
• the nitrogen atom constituting the functionalized imide components and functionalized amide components of B further is chemically bonded to an atom that constitutes the heterocycle.
• the functionalized imide components and functionalized amide components are incorporated in to the backbone of the oligomer or polymer and further include the heterocyclic group.
• the nitrogen atom constituting the functionalized imide components and functionalized amide components of B′ is chemically bonded to a group selected from C 1 -C 18 branched or straight chain alkyl, C 1 -C 18 alkyl or alkenyl substituted aryl, which is in turn chemically bonded to a pendant functional group selected from an amine group, amide group, carboxylic acid group, alcohol group or a group having the formula [CH 2 CH(R a )O] m R b wherein R a is hydrogen, methyl, ethyl, and phenyl, m is an integer from 2-20 and R b is independently hydrogen, methyl, ethyl, phenyl and benzyl.
• Preferred examples include C 1 -C 25 alkyl amines such as butyl amine, hexyl amine, octyl amine, decyl amine, dodecyl amine and stearyl amine; octyl amine; and C 1 -C 25 alkyl amides such as hexyl amide, n-octyl amide, decyl amide and stearyl amide.
• this invention provides a process for inhibiting corrosion of metallic components in contact with an aqueous system comprising the step of adding to the system an effective amount of a corrosion inhibiting polymer comprising chemical components A, B and C; wherein A optionally includes one or more end groups selected from initiator fragments, chain transfer fragments, solvent fragments and combinations thereof; wherein B includes at least one repeating unit selected from a functionalized imide component of Formula Ia, a functionalized amide component of Formula Ib and combinations of Ia and Ib; and wherein C represents at least one ethylenically unsaturated monomer component of Formula II.
• the components A, B and C are arranged randomly within the polymer and can be arranged sequentially in accordance with the invention.
• Component A includes for example any initiator fragment derived from any initiator useful in initiating free radical addition polymerization.
• initiator fragments include, but are not limited to, peroxyesters, such as t-butylperbenzoate, t-amylperoxybenzoate, t-butylperoxy-2-ethylhexonate, butylperacatate and t-butylperoxylmaleic acid; dialkylperoxides such as di-t-butylperoxide, dicumylperoxide and t-butylcumylperoxide; diacylperoxides such as benzoylperoxide, lauroylperoxide and acetylperoxide; hydroperoxides such as cumene hydroperoxides and t-butylhydroperoxide; azo compounds such as azonitriles, azaamidines, cyclic azoamidines, alkylazo compounds such as azodi
• Component A further includes for example end groups resulting from any chain transfer agent used in controlling the molecular weight of a free radical polymerization.
• Suitable chain transfer agents include but are not limited to alcohols, alkyl and aromatic thiols, alkyl phosphites, aryl phosphinic acids, alkyl phosphinic acids, hypophosphites, aldehydes, formates, alkylhalides and alkyl aromatic such as toluene, xylenes, and C9-10 alkylaromatics such as Aromatic 100.
• Component B refers to more than one of either a functionalized imide component or a functionalized amide component having respective Formulas Ia and lb.
• Preferred B components are selected from succinimide, glutarimide and combinations thereof.
• the nitrogen atom that constitute the imide or amide portion of component B must be chemically bonded to at least one atom of a R 2 group which in turn is chemically bonded to a pendant heterocycle.
• R 2 groups consisting of 2 to 8 consecutive atoms between the nitrogen atom of the imide or amide portion of B and the heterocycle are more preferred.
• R 2 groups consisting of 3 to 6 consecutive atoms between the imide or amide portion of B and the heterocycle are most preferred.
• Component C includes ethylenically unsaturated monomers of Formula III.
• suitable monomers include (meth)acrylic acid, methyl (meth)acrylate, hydroxy (meth)acrylate, 2-hydroxyethyl acrylate, 2-hydroxy propyl acrylate, butyl (meth)acrylate, 2-ethylhexyl acrylate, decyl acrylate, lauryl (meth)acrylate, isodecyl (meth)acrylate, hydroxyethyl (meth)acrylate, and hydroxypropyl (meth)acrylate; cyclic anhydrides such as maleic anhydride; anhydrides such as itaconic anhydride, and cyclohex-4-enyl tetrahydrophthalic anhydride; olefins such as ethylene, propylene, butylene, isobutylene, di-isobutylene, d-limonene; olefin oligomers
• component C refers to both acrylates or acrylamides and methacrylates and methacrylamides, respectively.
• Preferred monomers of component C include ethylene, propylene, isobutylene, di-isobutylene, propylene tetramer (C 12 -C 14 ), and propylene dimer trimer (C 18 -C 22 ).
• the corrosion inhibiting compositions usefully employed in the present invention have weight average molecular weights that range from 400 to 20,000. More preferred are compositions having weight average molecular weights that range from 400 to 10,000. Most preferred are compositions having weight average molecular weights that range from 400 to 5,000. Weight average molecular weights of the polymeric compositions were measured by GPC techniques using styrene as a standard.
• Polymers usefully employed according to the invention can be prepared by conventional emulsion, solution or suspension polymerization, including those processes disclosed in U.S. Pat. No. 4,973,409. Solution polymerization is preferred.
• Suitable solvents include for example water, dioxane, ketones such as 4-methylbutan-2-one, aromatic hydrocarbons such as toluene, xylene and xylene isomers, alcohols such as methanol and ethanol and ethers such as dioxane.
• Suitable reaction initiators include for example azo(bis)isobutyronitrile (AIBN), organic peroxides such as benzoyl peroxide, di-t-butyl peroxide, hydroperoxides such as t-butyl hydroperoxide and t-amyl hydroperoxide, hydrogen peroxide, sodium perborate, alkali metal persulfates and ammonium persulfate.
• AIBN azo(bis)isobutyronitrile
• organic peroxides such as benzoyl peroxide, di-t-butyl peroxide
• hydroperoxides such as t-butyl hydroperoxide and t-amyl hydroperoxide
• hydrogen peroxide sodium perborate
• alkali metal persulfates alkali metal persulfates and ammonium persulfate.
• the corrosion inhibiting polymer compositions are easily prepared in two steps.
• the first step includes for example polymerization of one or more monomers such as maleic anhydride with one or more ethylenically unsaturated monomer units of C such as di-isobutylene.
• the anhydride portion of the resulting co-polymer is then converted via one or more post polymerization functionalization reactions such as condensation, amidation, imidation, or esterification to afford polymer compositions of Formula 1a or 1b.
• the anhydride portion of the resulting co-polymer reacts with one or more heterocycles, such as an amino triazole or an amino pyridine via a condensation, to afford polymer compositions of Formula 1a or 1b.
• the compositions are easily prepared by polymerizing one or more functionalized monomer units of B with one or more ethylenically unsaturated monomer units of C to afford polymer compositions of Formula 1a or 1b.
• the polymer products of either process for the purpose of isolation may be subjected to partial or complete evaporation under reduced pressure.
• the unpurified reaction products may be used as the polymer composition of the present invention.
• the reaction products may also be purified.
• the pruification procedure consists of: a) evaporation of reaction solvent and washing with a water immiscible organic solvent such as ether, followed by evaporation of this solvent or b) evaporation of the reaction solvent, dissolving the polymer product in a suitable solvent and precipitating the polymer with a suitable non-solvent such as toluene or xylenes.
• the polymeric nature of the compositions coupled with high numbers of polar anchoring groups provide effective corrosion inhibition for metals and metal alloys by forming films exhibiting superior barrier properties over a broader range of pH, while remaining substantially impervious to corrosive agents present in aqueous systems and maintaining their anti-corrosive effectiveness over repeated additions of oxidizing biocides and corrosive agents such as chlorine for extended time periods.
• the corrosion inhibiting polymer compositions of the invention have the following advantages: improved chlorine resistance, low toxicity and environmental impact as compared to azoles such as TTA and BZT, a wide range of pH stability, formulated in safe and cost effective manner and are detected and monitored at ppm concentrations (also referred to as traceability). Improved chlorine resistance results in lower concentrations of metal ions such Cu 2+ discharged in to the aqueous system in compliance with EPA regulatory discharge restrictions, reduced galvanic corrosion, increased useful life of metallic components, reduced levels of polymer required for corrosion protection and elimination of odors associated with azoles. The low toxicity of the polymer compositions results in a lowered environmental impact as evidenced by relatively lower aquatic toxicological profiles.
• the polymer composition stability in a wide pH range allows for reductions or elimination of caustic providing reduced handling and shipping hazards.
• the polymers are made from inexpensive, commercially available monomer feedstocks and are easily formulated with other biocides, scale inhibitors and any other required additives known to be useful in treatment of aqueous systems.
• the heterocyclic group incorporated in the polymer provides a means to monitor low concentrations (ppm levels) of the polymer in the aqueous system via UV-vis absorption or fluorescence techniques, also referred to as traceability.
• An inert fluorescent tracer can also be incorporated in to the polymer as well to determine and monitor static and dynamic levels of the polymer in the aqueous system.
• the traceability of the polymers at ppm levels provides a means to detect the polymer concentration in the aqueous system and control the feed or dose rate required, resulting in significant cost performance.
• the amount of polymer compositions of Formula 1a or 1b used to treat the aqueous system varies according to the protective function required.
• the polymer compositions of the present invention can preferably be added to the aqueous system at active amounts ranging between 0.1 to 50,000 ppm (0.00001 to 5 weight %), preferably from 1 to 500 ppm, most preferably from 1 to 100 ppm, based on the weight of the aqueous system.
• the polymer compositions of this invention are used to prepare corrosion inhibiting formulations by combining the polymer with one or more additives known to be useful in treating aqueous systems such as for example biocidal compositions, any other corrosion inhibiting composition known in the art, scale inhibiting compositions, dispersants, defoamers, inert fluorescent tracers and combinations thereof.
• the corrosion inhibitors of the present invention can be formulated with surfactants, defoamers, co-solvents and hydrotropes or their pH can be altered with suitable acids or bases.
• suitable surfactants include but are not limited to Rhodafac® RS 610 or Rhodafac® RE 610 manufactured by Rhodia, Inc.
• suitable defoamers include but are not limited to GE silicone antifoam AF60.
• Suitable co-solvents include for example ethanol, isopropanol, ethylene glycol and propylene glycol.
• Suitable hydrotropes include Monatrope® 1250A manufactured by Uniqema, and sodium xylene sulfonate.
• Suitable scale inhibitors include for example polyphosphates and polycarboxylic acids and copolymers such as described in U.S. Pat. No. 4,936,987.
• the corrosion inhibitors of the present invention can also be used with other agents to enhance corrosion inhibition of copper, aluminum, mild steel, alloys of these and other metals.
• these agents include phosphates or phosphoric acid, polyphosphates such as tetrapotassium pyrophosphate and sodium hexametaphosphate, zinc, tolyltriazole, benzotriazole and other azoles, molybdate, chromate, phosphonates such as 1-hydroxyethylidene-1,1-diphosphonic acid, aminotris(methylene phosphonic acid), hydroxyphosphonoacetic acid and 2-phosphonobutane-1,2,4-tricarboxylic acid, polymeric corrosion inhibitors such as poly(meth)acrylic acid or polymaleic acid and copolymers of acrylic, methacrylic and maleic acid, as well as their alkali metal and alkaline earth metal salts.
• the corrosion inhibitors may also be used with other agents such as scale inhibitors and dispersants.
• agents such as scale inhibitors and dispersants.
• these agents include poly(meth)acrylic acid, polymaleic acid, copolymers of acrylic, methacrylic or maleic acid, phosphonates as previously described, and chelants such as nitrilotriacetic acid or ethylenediamine tetraacetic acid, as well as their metal salts.
• the agents described may be applied in a single formulation or applied separately.
• the polymer compositions of the invention are usefully employed as fluid additives such as coolants, antifreezes, metal working fluids, lubricants, brake fluids, transmission fluids, aircraft de-icing fluids, fluids for polishing electronic devices (e.g. in chemical mechanical planarization (CMP) processes), soldering additives, anti-abrasive compounds, direct metal treatment fluids, cleaning agents and detergents for photographic processes, anti-corrosive coatings, caulks, sealants and pressure sensitive adhesives in contact with metallic components.
• fluid additives such as coolants, antifreezes, metal working fluids, lubricants, brake fluids, transmission fluids, aircraft de-icing fluids, fluids for polishing electronic devices (e.g. in chemical mechanical planarization (CMP) processes), soldering additives, anti-abrasive compounds, direct metal treatment fluids, cleaning agents and detergents for photographic processes, anti-corrosive coatings, caulks, sealants and pressure sensitive adhesives in contact with metallic components.
• corrosion inhibiting compositions are usefully employeded in accordance with the present invention as fluid additives in contact with metallic components.
• the corrosion inhibiting composition are usefully employed as anti-corrosive coatings by techniques which are well known in the coatings art.
• the composition is an elastomeric coating, caulk, sealant or pressure sensitive adhesive composition is to be pigmented, at least one pigment is well dispersed in an aqueous medium under high shear such as is afforded by a COWLES® mixer or, for more viscous compositions such as caulks and sealants, a high intensity mixer or mill.
• the waterborne polymer is added under lower shear stirring along with other elastomeric coating, caulk, sealant or pressure sensitive adhesive adjuvants as desired.
• the aqueous emulsion polymer may be included in the pigment dispersion step.
• the aqueous composition may contain conventional elastomeric coating, caulk, sealant or pressure sensitive adhesive adjuvants such as, for example, tackifiers, pigments, emulsifiers, coalescing agents, buffers, neutralizers, thickeners or rheology modifiers, humectants, wetting agents, biocides, plasticizers, antifoaming agents, colorants, waxes, and anti-oxidants.
• the solids content of the aqueous coating composition may be from about 10% to about 85% by volume.
• the viscosity of the aqueous composition may be from 0.05 to 2000 Pa.s (50 cps to 2,000,000 cps), as measured using a Brookfield viscometer; the viscosities appropriate for different end uses and application methods vary considerably.
• the oligomeric and polymeric corrosion inhibiting compositions may be applied by conventional application methods such as, for example, brushing and spraying methods such as, for example, roll coating, dipping doctor-blade application, printing methods, an aerosol, air-atomized spray, air-assisted spray, airless spray, high volume low pressure spray, air-assisted airless spray, caulk guns, and trowels.
• brushing and spraying methods such as, for example, roll coating, dipping doctor-blade application, printing methods, an aerosol, air-atomized spray, air-assisted spray, airless spray, high volume low pressure spray, air-assisted airless spray, caulk guns, and trowels.
• the polymeric corrosion inhibiting compositions may be applied to substrates including but not limited to for example, plastic including sheets and films, wood, previously painted surfaces, cementitious substrates, asphaltic substrates or the like, with or without a prior substrate treatment such as an acid etch or corona discharge or a primer.
• substrates including but not limited to for example, plastic including sheets and films, wood, previously painted surfaces, cementitious substrates, asphaltic substrates or the like, with or without a prior substrate treatment such as an acid etch or corona discharge or a primer.
• MMA methyl methacrylate
• DI water deionized water
• a 1.8 L reactor was charged with 150.8 g of maleic anhydride flakes, 485 g of dry reagent grade xylenes, 179.4 g diisobutylene and 0.3 g of p-toluene sulfonic acid. The reactor was sealed. It was flushed with nitrogen and a vacuum of-15 psig. was established. Heating to 160° C. was started and the initiator feed was prepared by dissolving 27.5 g of di-t-butylperoxide in 90 g of xylenes. When the reactor temperature had reached 160° C. the initiator solution was fed for 15 minutes at 2 g/min. Heating is stopped and the reaction is exothermic to 175° C. and 32 psig.
• the remaining initiator solution is added at 1 g/min for 85 min. During this time the reactor is maintained at 175-180° C. with stirring at 160 rpm. After the initiator feed is the heating is continued for 30 min. The reaction mixture is cooled and the reactor is drained at room temperature and pressure. This procedure gives 928 g of solution containing 35.2% solids. This solution (P1) is used for the functionalization process.
• a stock solution was prepared containing 1000 ppm of phosphoric acid (as PO 4 3 ⁇ , 1.21 g of 85% H 3 PO 4 ), 625 ppm of 1-hydroxyethylidene-1,1-disphosphonic acid (as PO 4 3 ⁇ , 1.13 g of 60% HEDP, Dequest® 2010, Solutia) and 625 ppm of Acumer® 2000 copolymer supplied at 39.5% actives by Rohm and Haas Company (1.58 g). To complete the stock solution, water was added to the mixture to afford a total weight of 998 g. The pH was adjusted to 10.5 and then 1000 ppm tetrapotassium pyrophosphate (as P 4 3 ⁇ , 1.74 g of TKPP) was added. The pH of the final mixture was adjusted to 11.0.
• phosphoric acid as PO 4 3 ⁇ , 1.21 g of 85% H 3 PO 4
• Each polymer was prepared as 1000 ppm (as actives) in an appropriate solvent (water, methanol or isopropanol).

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• Preventing Corrosion Or Incrustation Of Metals (AREA)
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• 2002
  • 2002-08-20 CA CA002398934A patent/CA2398934A1/fr not_active Abandoned
  • 2002-08-21 EP EP02255835A patent/EP1288337A3/fr not_active Withdrawn
  • 2002-08-29 MX MXPA02008480A patent/MXPA02008480A/es unknown
  • 2002-08-29 KR KR1020020051379A patent/KR20030020828A/ko not_active Application Discontinuation
  • 2002-09-02 JP JP2002256999A patent/JP2003183862A/ja not_active Withdrawn
  • 2002-09-02 CN CN02141602A patent/CN1407136A/zh active Pending
  • 2002-09-04 US US10/234,883 patent/US20030063999A1/en not_active Abandoned

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