Classifications

• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
  • C10L3/00—Gaseous fuels; Natural gas; Synthetic natural gas obtained by processes not covered by subclass C10G, C10K; Liquefied petroleum gas
  • C10L3/06—Natural gas; Synthetic natural gas obtained by processes not covered by C10G, C10K3/02 or C10K3/04
  • C10L3/10—Working-up natural gas or synthetic natural gas
  • C10L3/107—Limiting or prohibiting hydrate formation
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
  • C09K8/52—Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
  • C10L1/00—Liquid carbonaceous fuels
  • C10L1/10—Liquid carbonaceous fuels containing additives
  • C10L1/14—Organic compounds
  • C10L1/22—Organic compounds containing nitrogen
  • C10L1/221—Organic compounds containing nitrogen compounds of uncertain formula; reaction products where mixtures of compounds are obtained
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
  • C10L3/00—Gaseous fuels; Natural gas; Synthetic natural gas obtained by processes not covered by subclass C10G, C10K; Liquefied petroleum gas
  • C10L3/06—Natural gas; Synthetic natural gas obtained by processes not covered by C10G, C10K3/02 or C10K3/04
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
  • F17D—PIPE-LINE SYSTEMS; PIPE-LINES
  • F17D1/00—Pipe-line systems
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
  • F17D—PIPE-LINE SYSTEMS; PIPE-LINES
  • F17D1/00—Pipe-line systems
  • F17D1/08—Pipe-line systems for liquids or viscous products
  • F17D1/16—Facilitating the conveyance of liquids or effecting the conveyance of viscous products by modification of their viscosity
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
  • F17D—PIPE-LINE SYSTEMS; PIPE-LINES
  • F17D3/00—Arrangements for supervising or controlling working operations
  • F17D3/12—Arrangements for supervising or controlling working operations for injecting a composition into the line
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K2208/00—Aspects relating to compositions of drilling or well treatment fluids
  • C09K2208/22—Hydrates inhibition by using well treatment fluids containing inhibitors of hydrate formers

Definitions

• the present invention relates to a method of inhibiting gas hydrates comprising contacting gas hydrates with a hybrid mixture comprising a derivative of at least one
• Gas hydrates also called clathrate hydrates, are crystalline water-based solids physically resembling ice, in which small non polar molecules (typically gases) are trapped inside "cages" of hydrogen bonded water molecules.
• gases typically gases
• Most low molecular weight gases including O 2 , H 2 , N 2 , CO 2 , CH 4 , H 2 S, Ar, Kr, and Xe
• gas hydrates may occur when water is present in mineral oil mixtures or in natural gas mixtures in which gas hydrate crystals may agglomerate and plug, for example, pipelines.
• hybrid mixtures according to the present invention can address the problems associated with conventional gas hydrate inhibitors, including improving biodegradability.
• Hybrid mixtures comprise a naturally occurring oligomer or polymer and a synthetically derived oligomer or polymer.
• new combinations of naturally derived hydroxyl containing chain transfer agents in gas hydrate inhibition applications have been discovered that were heretofore previously unknown.
• the invention is directed to a method of inhibiting gas hydrates comprising contacting a gas hydrate with a hybrid mixture formed by combining at least one ethylenically unsaturated monomer with a solution of a naturally derived hydroxyl containing chain transfer agent and an initiator at a temperature effective to activate the initiator.
• the Figure is a chart illustrating rapid hydrate formation time and temperature data from the evaluation of the hybrid mixture of Synthesis Example 24.
• the invention is directed to a method of inhibiting gas hydrates.
• the method includes contacting the gas hydrates with a hybrid mixture.
• the hybrid mixtures of the instant invention are formed by combining at least one ethylenically unsaturated monomer with a solution containing a naturally derived hydroxyl containing chain transfer agent and an initiator at a temperature effective to activate the initiator.
• the invention relates to a method of inhibiting gas hydrates wherein the method comprises contacting a gas hydrate with a hybrid mixture comprising a derivative of at least one ethylenically unsaturated monomer and a naturally derived hydroxyl containing chain transfer agent.
• the hybrid mixture that is used to inhibit gas hydrates is an intimate mixture of at least one naturally derived hydroxyl containing chain transfer agent and a polymer comprised of at least one ethylenically unsaturated monomer. This intimate mixture can be prepared by polymerization of the at least one ethylenically unsaturated monomer, by means known to those skilled in art, in the presence of the at least one naturally derived hydroxyl containing chain transfer agent.
• the intimate mixture can also be prepared by coprocessing the at least one naturally derived hydroxyl containing chain transfer agent with the polymer comprised of at least one ethylenically unsaturated monomer under conditions of high temperature or pressure or both.
• An example of coprocessing under conditions of high pressure and high temperature is to co-jet cook the at least one naturally derived hydroxyl containing chain transfer agent with the polymer comprised of at least one ethylenically unsaturated monomer.
• Another example of coprocessing is heating the at least one naturally derived hydroxyl containing chain transfer agent with the polymer comprised of at least one ethylenically unsaturated monomer in aqueous solution under atmospheric pressure.
• the derivative of the at least one ethylenically unsaturated monomer is a polymer including the ethylenically unsaturated monomer.
• the hybrid mixture is a hybrid copolymer composition prepared by reacting at least one ethylenically unsaturated monomer with a solution of a naturally derived hydroxyl containing chain transfer agent and an initiator.
• One conventional method of making hybrid mixtures utilizes water soluble monomers in the presence of an aqueous solution of a naturally derived, hydroxyl containing material as a chain transfer agent. Such a method is disclosed in U.S. Patent application publication number US 2007-0021577 Al, which is wholly incorporated herein by reference.
• the derivative is a polymeric chain comprised of the ethylenically unsaturated monomer that is attached covalently to the naturally derived hydroxyl containing chain transfer agent.
• the hybrid copolymer composition can be prepared with a naturally derived hydroxyl containing chain transfer agent and still maintain the functionality of the synthetic polymers portion.
• the reaction proceeds according to the following mechanism: ⁇ ⁇ I 2 ⁇
• Hybrid copolymer composition mixture of (a) and (b)
• the initiator I forms free radicals which reacts with the monomer and initiates the synthetic polymer chain. This then propagates by reacting with several monomer moieties. Termination is then by chain transfer which abstracts a proton from the chain transfer agent. This terminates the hybrid synthetic polymer (a) and produces a free radical on the chain transfer agent. The chain transfer agent then reacts with several monomer moieties to form a species in which the naturally derived hydroxyl containing chain transfer agent is connected to the synthetic polymer chain. This species can then terminate by chain transfer mechanism or reaction with an initiator fragment or by some other termination such as combination or disproportionation reaction to produce the hybrid copolymer (b). If the termination is by chain transfer, then 3 ⁇ 4 is H (abstracted from the chain transfer moiety) and the chain transfer agent can then initiate another chain.
• a “hybrid copolymer composition” is a mixture of (a) a hybrid synthetic copolymer and (b) a hybrid copolymer.
• the hybrid copolymer composition thus contains the two moieties, (a) and (b), with a minimum amount of the hybrid synthetic copolymer (a) since this component generates the chain transfer which leads to the formation of the hybrid copolymer (b).
• the hybrid copolymer composition may contain a certain amount of the unreacted chain transfer agent.
• hybrid copolymer refers to a copolymer of synthetic monomers with an end group containing the naturally derived hydroxyl containing chain transfer agent which is a result of the hybrid synthetic copolymer chain transfer.
• naturally derived hydroxyl containing chain transfer agent means a hydroxyl containing moiety obtained from plant sources directly or by enzymatic or fermentation processes.
• the hybrid copolymer has the following structure:
• C is a moiety derived from the naturally derived hydroxyl containing chain transfer agent
• M c is the synthetic portion of the hybrid copolymer derived from one or more ethylenically unsaturated monomers
• R ⁇ H from chain transfer or I from reaction with the initiator radical or the naturally derived hydroxyl containing chain transfer agent or another moiety formed from a termination reaction.
• the attachment point between C and Mh c is through an aldehyde group in C which results in the link between C and M c being a carbonyl moiety.
• the naturally derived hydroxyl containing chain transfer agent is a saccharide/polysaccharide with an aldehyde group as the reducing end group, then the hybrid copolymer can be represented by the structure:
• S is a saccharide repeat unit from the saccharide/polysaccharide chain transfer agent and s is an integer from 0 to 1000 and p is an integer that is 3, 4 or 5.
• the hybrid copolymer can be represented by the structure:
• hybrid synthetic copolymer is a synthetic polymer derived from synthetic monomers with a hybrid initiator fragment as one end group. The other end group is a proton resulting from chain transfer to the naturally derived hydroxyl containing chain transfer agent.
• synthetic monomer means any ethylenically unsaturated monomer which can undergo free radical polymerization.
• an exemplary hybrid synthetic copolymer has the following structure:
• M sc is the synthetic portion of the hybrid synthetic copolymer derived from one or more ethylenically unsaturated monomers.
• H is the proton abstracted from the natural chain transfer agent
• M sc is the synthetic portion of the hybrid synthetic copolymer derived from one or more ethylenically unsaturated monomers.
• hybrid initiator fragment incorporated into the hybrid synthetic copolymer will depend on the hybrid initiator used. For example, sodium persulfate, potassium persulfate and ammonium persulfate will incorporate sulfate initiator fragments, whereas an azo initiator, such as 2,2'-Azobis(2- methylpropionamidine)dihydrochloride, will incorporate a 2-methyl propane propionamidine hydrochloride fragment.
• the minimum amount of the hybrid synthetic copolymer will depend on the relative amounts of synthetic monomer, initiator and naturally derived hydroxyl containing chain transfer agent.
• a secondary chain transfer agent may also be included.
• the secondary chain transfer agent may be less than 20 weight percent of the hybrid polymer.
• solution of the naturally derived hydroxyl containing chain transfer agent may be substantially free of secondary transfer agents.
• the process may further comprise catalyzing the polymerizing step with an initiator that is substantially free of a metal ion initiating system at a temperature sufficient to activate said initiator.
• Molecular weight of the hybrid synthetic polymer is determined by the relative amounts of synthetic monomer, initiator and naturally derived hydroxyl containing chain transfer agent.
• the weight average molecular weight of the hybrid copolymer composition may be less than about 500,000, preferably less than 300,000 and most preferably less than 100,000.
• the hybrid copolymer composition may be water soluble.
• water soluble is defined as having a solubility of greater than about 0.1 grams per 100 grams of water at 25 C and preferably 1 gram per 100 grams of water at 25 C.
• the hybrid synthetic copolymer will have a hybrid initiator fragment (I) and some of the hybrid copolymer chains will have a natural chain transfer agent at one end and a hybrid initiator fragment (where R ⁇ is I) at the other end of the synthetic polymer chain.
• hybrid initiator fragment is any fragment of the hybrid initiator that gets incorporated into a synthetic polymer derived from a hybrid initiator.
• I is preferably 0.01 to 20 mole% of Mh c + Mh sc and more preferably I is 0.1 to 15 mole% of M c + M sc and most preferably I is 1 to 10 mole% of M c + Mh sc .
• the naturally derived hydroxyl containing chain transfer agents include, but are not limited, to small molecules such as glycerol, citric acid, lactic acid, tartaric acid, gluconic acid, ascorbic acid, and glucoheptonic acid.
• the naturally derived hydroxyl containing chain transfer agents may also include saccharides or derivatives thereof.
• Suitable saccharides include, for example, monosaccharides and disaccharides such as sugars, such as glucose, galactose, mannose, fructose, arabinose, xylose, maltose, lactose, trehalose, cellobiose, maltotriose, and sucrose, as well as larger molecules such as oligosaccharides and polysaccharides (e.g., corn syrup solids, maltodextrins, pyrodextrins and starches).
• the naturally derived chain transfer agent is maltodextrin, pyrodextrin or a low molecular weight starch.
• the chain transfer reaction does not work well when the chain transfer agent is not soluble in the system.
• high molecular weight starches such as those having molecular weights in the millions or those in granular form, are water dispersible and not water soluble.
• the average molecular weight of the chain transfer agent is preferably less than about 500,000 based on a starch standard. Starches having such exemplary molecular weights are water soluble.
• the average molecular weight (Mw) of the chain transfer agent may be less than about 100,000.
• the weight average molecular weight of the chain transfer agent may be less than about 50,000.
• the weight average molecular weight of the chain transfer agent may be less than about 10,000. It has also been determined that for applications in which dispersancy and scale control is particularly desirable, a lower molecular weight, such as 10,000, of the chain transfer agent provides improved performance.
• the molecular weight of the polysaccharide was determined by the procedure outlined below:
• Guard column is TSKgel Guard PWxl 6.0mm x 4cm (all made by Tosoh Bioscience)
• the column bank was controlled to 5°C above ambient temperature. Usually 30°C.
• HETA Hydroethylstarch
• Sample Preparation The samples were prepared by dissolving the polymer in the mobile phase at a 0.1% concentration.
• Injection Volume 450 ⁇ for the standard and sample.
• the standards are injected and a first or second order calibration curve is built.
• a calibration curve is first built with the samples of the standards.
• the molecular weight of the unknown sample is then determined by comparing its elution time with the elution time of the standards.
• the naturally derived hydroxyl containing chain transfer agents also may include cellulose and its derivatives, as well as inulin and its derivatives, such as carboxymethyl inulin.
• the cellulosic derivatives include plant heteropolysaccharides commonly known as hemicelluloses which are by products of the paper and pulp industry. Hemicelluloses include xylans, glucuronoxylans, arabinoxylans, arabinogalactans, glucomannans, and xyloglucans. Xylans are the most common heteropolysaccharide and are preferred.
• cellulosic derivatives such as heteropolysaccharides such as xylans may be present in an amount of from about 0.1 % to about 98% by weight, based on the total amount of the hybrid copolymer.
• the naturally derived chain transfer agents may be maltodextrins, pyrodextrins and chemically modified versions of maltodextrins and pyrodextrins.
• the naturally derived chain transfer agent may be cellulose of inulin or chemically modified cellulose or inulin or a heteropolysaccharide such as xylan or a lignin derivative, such as lignosulfonate.
• the naturally derived hydroxyl containing chain transfer agents also may include polysaccharides and polysaccharide gums.
• polysaccharides and polysaccharide gums include but are not limited guar gum, locust bean gum, gum arabic alginic acid, pectin, chitin, chitosan, xanthan gum, and tamarind kernel gum.
• the naturally derived chain transfer agents can be used as obtained from their natural source or they can be chemically modified. Chemical modification includes hydrolysis by the action of acids, enzymes, oxidizers or heat, esterification or etherification.
• the modified naturally derived chain transfer agents, after undergoing chemical modification may be cationic, anionic, non-ionic or amphoteric or hydrophobically modified.
• the hybrid copolymer may optionally be formed by polymerization catalyzed by, for example, a non-metal based radical initiator system.
• the gas hydrate inhibitor comprises a hybrid mixture wherein the derivative of the at least one ethylenically unsaturated monomer includes at least one anionic ethylenically unsaturated monomer.
• anionic ethylenically unsaturated monomer means an ethylenically unsaturated monomer which is capable of introducing a negative charge to the anionic hybrid mixture.
• anionic ethylenically unsaturated monomers can include, but are not limited to, acrylic acid, methacrylic acid, ethacrylic acid, -chloro-acrylic acid, -cyano acrylic acid, / 5-methyl-acrylic acid (crotonic acid), -phenyl acrylic acid, 5-acryloxy propionic acid, sorbic acid, -chloro sorbic acid, angelic acid, cinnamic acid, p-chloro cinnamic acid, / 3-styryl acrylic acid (l-carboxy-4-phenyl butadiene- 1,3), itaconic acid, maleic acid, citraconic acid, mesaconic acid, glutaconic acid, aconitic acid, fumaric acid, tricarboxy ethylene, muconic acid, 2-acryloxypropionic acid, 2-acrylamido-2-methyl propane sulfonic acid, vinyl sulfonic acid, sodium methallyl sulfonate, s
• Moieties such as maleic anhydride or acrylamide that can be derivatized (hydrolyzed) to moieties with a negative charge are also suitable.
• Combinations of anionic ethylenically unsaturated monomers can also be used.
• the anionic ethylenically unsaturated monomer may preferably be acrylic acid, maleic acid, methacrylic acid, itaconic acid, 2-acrylamido-2-methyl propane sulfonic acid or mixtures thereof.
• the anionic hybrid mixture comprises an anionic hybrid copolymer composition, which may contain 1 to 99.5 weight percent of the naturally derived hydroxyl containing chain transfer agent based on the weight of the hybrid copolymer mixture.
• an anionic hybrid copolymer composition which may contain 1 to 99.5 weight percent of the naturally derived hydroxyl containing chain transfer agent based on the weight of the hybrid copolymer mixture.
• the present invention relates to gas hydrate inhibitors comprising hybrid mixtures in which the at least one ethylenically unsaturated monomer includes at least one non-anionic ethylenically unsaturated monomer.
• a hybrid mixture that is non-anionic includes mixtures produced from at least one cationic ethylenically unsaturated monomer or at least one nonionic ethylenically unsaturated monomer or a combination of cationic and non- ionic ethylenically unsaturated monomers and a naturally derived hydroxyl containing chain transfer agent.
• the "cationic ethylenically unsaturated monomer” is capable of introducing a positive charge to a non-anionic hybrid mixture.
• the cationic ethylenically unsaturated monomer has at least one amine functionality.
• Cationic derivatives of non-anionic hybrid copolymer compositions may be formed by forming amine salts of all or a portion of the amine functionality, by quaternizing all or a portion of the amine functionality to form quaternary ammonium salts, or by oxidizing all or a portion of the amine functionality to form N-oxide groups.
• amine salt means the nitrogen atom of the amine functionality is covalently bonded to from one to three organic groups and is associated with an anion.
• quaternary ammonium salt means that a nitrogen atom of the amine functionality is covalently bonded to four organic groups and is associated with an anion.
• cationic derivatives can be synthesized by functionalizing the monomer before polymerization or by functionalizing the polymer after polymerization.
• cationic ethylenically unsaturated monomers include, but are not limited to, N,N dialkylaminoalkyl(meth)acrylate, N-alkylaminoalkyl(meth)acrylate, N,N dialkylaminoalkyl(meth)acrylamide and N - alkylaminoalkyl(meth)acrylamide, where the alkyl groups are independently C 1-18 aliphatic, cycloaliphatic, aromatic, or alkyl aromatic and the like.
• Aromatic amine containing monomers such as vinyl pyridine and vinyl imidazole may also be used.
• monomers such as vinyl formamide, vinyl acetamide and the like which generate amine moieties on hydrolysis may also be used.
• nonionic ethylenically unsaturated monomer means an ethylenically unsaturated monomer which does not introduce a charge in to the non-anionic hybridmixture.
• These nonionic ethylenically unsaturated monomers include, but are not limited to, acrylamide, methacrylamide, N alkyl(meth)acrylamide, N,N dialkyl(meth)acrylamide such as N,N dimethylacrylamide, hydroxyalkyl(meth)acrylates, alkyl(meth)acrylates such as methylacrylate and methylmethacrylate, vinyl acetate, vinyl morpholine, vinyl pyrrolidone, vinyl caprolactam, vinyl formamide, vinyl acetamide, ethoxylated alkyl, alkaryl or aryl monomers such as methoxypoly ethylene glycol (meth)acrylate, allyl glycidyl ether, allyl alcohol, glycerol (meth)
• the nonionic ethylenically unsaturated monomer is preferably water soluble.
• the preferred nonionic ethylenically unsaturated monomers are acrylamide, methacrylamide, N methyl(meth)acrylamide, N,N dimethyl(meth)acrylamide, vinyl pyrrolidone, vinyl formamide, vinyl acetamide and vinyl caprolactam.
• Hybrid mixtures useful in gas hydrate inhibitor compositions include both anionic and non-anionic intimate mixtures and/or hybrid copolymer compositions.
• a gas hydrate inhibitor composition includes at least one nonionic ethylenically unsaturated monomer which is a vinyl lactam or vinyl lactam with a co-monomer, such as a non-anionionic co- monomer.
• the at least one nonionic ethylenically unsaturated monomer is N-vinyl pyrrolidone or vinyl caprolactam or combinations thereof.
• the nonionic ethylenically unsaturated monomer is -a combination of vinyl pyrrolidone or vinyl caprolactam present in a ratio in a range of from about 25:75 to about 75:25 vinyl pyrrolidone to vinyl caprolactam.
• the gas hydrate inhibitor composition includes a naturally derived hydroxyl containing chain transfer agent which is a polysaccharide.
• the polysaccharide can be hydro lyzed starch having a DE of greater than 5.
• the polysaccharide is maltodextrin having a DE greater than 5.
• the maltodextrin has a DE of 10 or greater.
• the naturally derived hydroxyl containing chain transfer agent comprises maltodextrin or corn syrup solids.
• the maltodextrin or corn syrup solids preferably has a dextrose equivalent (DE) of greater than 5.
• DE dextrose equivalent
• the maltodextrin or corn syrup solids has a DE of 10 or greater.
• DE dextrose equivalent
• dextrose equivalent is a measure of the amount of reducing sugars present in a sugar product, relative to glucose, and is a well known term of art.
• hybrid copolymer composition and/or intimate mixture is made in the presence of a hybrid initiator.
• hybrid initiators include free radical initiators, initiating systems excluding metal ion based initiators or metal ion- based initiators.
• the hybrid initiators are free radical initiators or initiating systems excluding metal ion based initiators or initiating systems.
• the hybrid initiators preferably are not free radical abstractors but promote chain transfer.
• the hybrid initiator is preferably water soluble.
• Exemplary hybrid initiators include, but are not limited to, peroxides, azo initiators as well as redox systems like tert-butyl hydroperoxide and erythorbic acid, peroxide such as persulfate and an amine such as hydroxylamine sulfate, persulfate and sodium formaldehyde sulfoxylate etc.
• the hybrid initiators may include both inorganic and organic peroxides.
• Suitable inorganic peroxides include sodium persulfate, potassium persulfate and ammonium persulfate.
• Azo initiators such as water soluble azo initiators, may also be suitable hybrid initiators.
• Water soluble azo initiators include, but are not limited to, 2,2'-Azobis[2-(2- imidazolin-2-yl)propane]dihydrochloride, 2,2'-Azobis[2-(2-imidazolin-2-yl)propane]disulfate dihydrate, 2,2'-Azobis(2-methylpropionamidine)dihydrochloride, 2,2'-Azobis[N-(2- carboxyethyl)-2-methylpropionamidine]hydrate, 2,2'- Azobis ⁇ 2- [ 1 -(2-hydroxyethyl)-2- imidazolin-2-yl]propane ⁇ dihydrochloride, 2,2'-Azobis[2-(2-imidazol
• the initiator is a nonionic initiator.
• exemplary hybrid initiators include, but are not limited to, peroxides, azo initiators as well as redox systems like tert-butyl hydroperoxide and erythorbic acid, peroxide such as persulfate and an amine such as hydroxylamine sulfate, persulfate and sodium formaldehyde sulfoxylate etc .
• the initiator is an Azo initiator, such as 2,2'-Azobis[2-methyl-N-(2- hydroxyethyl)propionamide] or 2,2'-Azobis(2-methylpropionamidine)dihydrochloride.
• the hybrid mixtures utilized as gas hydrate inhibitors in accordance with the present invention may be used either in pure aqueous solution or alternatively in solvent mixtures, such as in water/alcohol mixtures.
• a suitable solvent may include ethylene glycol.
• the hybrid mixtures may be made into powders by removing the solvent and drying. Accordingly, the hybrid mixtures may be redispersed or redissolved by introducing the powdered mixtures into the water- containing media in which gas hydrate formation occurs.
• the hybrid mixtures are added to the liquid systems, such as mineral oil mixtures or natural gas mixtures, in an amount which one of ordinary skill in the art would select based on the particular application and conditions.
• the hybrid mixtures are hybrid copolymer compositions encompassing both anionic and non-anionic hybrid copolymer compositions which are latently-detectable, which means that they will not be detectable in the visible light range until the hybrid copolymer composition is contacted with a photoactivator.
• the "photoactivator” is an appropriate reagent or reagents which, when present in effective amounts, will react with the hybrid copolymer composition, thereby converting the hybrid copolymer composition into a chemical species which strongly absorbs in the region from about 300 to about 800 nanometers when activated with, for example, sulfuric acid and phenol.
• the activated hybrid copolymer composition will absorb in the region from about 400 to about 700 nanometers.
• a latently detectable moiety of this invention will be formed from a naturally derived hydroxyl containing chain transfer agent especially when it is saccharide or polysaccharide moiety.
• the photoactivator may be the combination of sulfuric acid and phenol (see Dubois et al, Anal. Chem. 28 (1956) p. 350 and Example 1 of U.S patent no. 5,654,198, which is incorporated in its entirety by reference herein).
• Polymers typically tagged with latently detectable moieties exhibit a drop in efficacy when compared to polymers without these groups. This is especially true when the weight percent of the latently detectable moiety is over 10 or 20 percent of the polymer.
• the hybrid copolymers compositions of the present invention perform well even when containing 50 percent or more of the latently detectable moiety.
• the advantages of good performance and ready detectability are provided, which allow monitoring the system and controlling scale without over dosing the scale control polymer.
• the ethylenically unsaturated monomer of the hybrid mixture may optionally be selected from at least one ester monomer.
• ester monomers include, but are not limited to, esters derived from dicarboxylic acid as well as hydroxyalkyl esters.
• Suitable ester monomers derived from dicarboxylic acid include, but are not limited to, monomethylmaleate, dimethylmaleate, monomethylitaconate, dimethylitaconate, monoethylmaleate, diethylmaleate, monoethylitaconate, diethylitaconate, monobutylmaleate, dibutylmaleate, monobutylitaconate and dibutylitaconate.
• Suitable hydroxyalkyl esters include, but are not limited to, hydroxy ethyl (meth)acrylate, hydroxy propyl (meth)acrylate, hydroxy butyl (meth)acrylate and the like.
• the invention relates to an "amphoteric hybrid mixture" containing both anionic and cationic groups.
• the anionic moieties can be on the natural component with the cationic moieties on the synthetic component or the cationic moieties can be on the natural component with the anionic moieties on the synthetic component or combinations thereof.
• the anionic material can be an oxidized starch and the cationic moiety can be derived from cationic ethylenically unsaturated monomers such as diallyldimethylammonium chloride.
• the oxidized starch itself may first be reacted with cationic substituent such as 3-chloro-2- hydroxypropyl) trimethylammonium chloride and then reacted with a synthetic anionic or cationic monomer or mixtures thereof.
• cationic substituent such as 3-chloro-2- hydroxypropyl) trimethylammonium chloride
• a cationic starch may be reacted with an anionic monomer.
• the cationic and anionic moieties may be on the synthetic component of these polymers.
• These amphoteric hybrid copolymer composition containing both anionic and cationic groups are particularly useful in detergent formulations as dispersants and cleaning aids. It is understood that these polymers will contain both a natural component and a synthetic component.
• the cationic moieties are preferably present in the range of 0.001 to 40 mole% of the anionic moieties, more preferably the cationic moieties are present in the range of 0.01 to 20 mole% of the anionic moieties, and most preferably the cationic moieties are present in the range of 0.1 to 10 mole% of the anionic moieties.
• Polymers formed from cationic ethylenically unsaturated monomers generally tend to have poorer toxicological and environmental profiles compared to polymers formed from non- cationic ethylenically unsaturated monomers. Therefore, it may be necessary to minimize the level of cationic ethylenically unsaturated monomer used in preparing the amphoteric hybrid mixture.
• the cationic ethylenically unsaturated monomer when a cationic ethylenically unsaturated monomer is used to produce an amphoteric hybrid mixture, is preferably present up to 10 mole% of the hybrid mixture, more preferably the cationic ethylenically unsaturated monomer is preferably present up to 6 mole% of the hybrid mixture, and most preferably the cationic ethylenically unsaturated monomer is preferably present up to 5 mole% of the hybrid mixture.
• the invention relates to hybrid mixtures derived from monomers produced from natural sources such as acrylamide produced by fermentation.
• monomers produced from natural sources increase the renewable carbon content of the polymers of this invention.
• the synthetic component of the hybrid copolymer composition is derived from N-vinyl pyrrolidone; the naturally occurring portion of the hybrid copolymer composition is derived from a DE 9.0-12.0 maltodextrin, which is the naturally derived hydroxyl containing chain transfer agent.
• a DE of 9.0-12.0 roughly corresponds to a glucose degree of polymerization of 10-13, or a number average molecular weight (Mn) of 1600-2100.
• the amount of the hybrid copolymer composition derived from maltodextrin was 50 wt.% (based on dry polymer). A critical feature of this synthesis is that a maltodextrin with a DE>5 was used.
• a four-neck round bottom flask was equipped with a mechanical stirrer, reflux condenser, a 60 mL addition funnel and a 125 mL addition funnel.
• the weight of the flask with stirring apparatus alone was 483.20 g.
• To the flask were charged 23.5671 g deionized water and 26.4966 g Maltrin Ml 00 maltodextrin. The mixture was stirred until a homogeneous solution was obtained.
• the reaction was warmed to 95 °C using a thermostatted oil bath. When the temperature reached about 53 °C, 6.2436 g N-vinyl pyrrolidone and 0.0654 g VA-086 were added in one portion and heating was continued. A transient light pink color was noted after the addition; the mixture remained clear. When temperature reached 93 °C, drop- wise addition over 2.45 h of the contents of the two addition funnels was commenced. The rate of addition was fairly uniform although adjustments to the rate were occasionally necessary to keep the addition rates even.
• the polymer solution was turbid and phase separation appeared to have occurred.
• the polymer was diluted in the reaction vessel with a total of 83.3 g deionized water. A clear, apparently single phase solution was obtained.
• the yield of polymer solution measured in the flask was 246.08 g.
• Theoretical solids of the polymer solution (based on the amount of monomer and maltodextrin added divided by the total yield of polymer solution): 20.3%.
• the experimental solids (gravimetric at 130 °C for 1.5 h, duplicate runs) was 19.9%. This corresponds to a monomer conversion of 96%.
• the synthetic component of the hybrid copolymer composition is derived from N-vinyl pyrrolidone; the naturally occurring portion of the hybrid copolymer composition is derived from a DE 9.0-12.0 maltodextrin, which is the naturally derived hydroxyl containing chain transfer agent.
• a DE of 9.0-12.0 roughly corresponds to a glucose degree of polymerization of 10-13, or a number average molecular weight (Mn) of 1600-2100.
• the amount of the hybrid copolymer composition derived from maltodextrin was 50 wt.% (based on dry polymer). A critical feature of this synthesis is that a maltodextrin with a DE>5 was used.
• N-vinyl pyrrolidone (Aldrich) 18.7547 g Deionized water 54.5410 g A four-neck round bottom flask was equipped with a mechanical stirrer, reflux condenser, and two 125 mL addition funnels. The weight of the flask with stirring apparatus alone was 479.19 g. To the flask were charged 14.49 g deionized water, 6.29 g N- vinyl pyrrolidone, and 0.0624 g Wako VA-086. The mixture was stirred until a homogeneous solution was obtained.
• the reaction was warmed to 95 °C using a thermostatted oil bath. When temperature reached 93 °C, drop-wise addition over 3 h of the contents of the two addition funnels was commenced. The rate of addition was fairly uniform although adjustments to the rate were occasionally necessary to keep the addition rates even. After the addition was complete, heating at 95 °C was continued for an additional 3 h. At the conclusion of the reaction, the polymer solution was clear.
• Additional hybrid copolymer compositions were prepared by Synthesis Methods A or B. The compositions are summarized in Table 1 below. Table 1. Additional hybrid copolymer compositions.
• the synthetic component of the hybrid copolymer composition is derived from N-vinyl pyrrolidone; the naturally occurring portion of the hybrid copolymer composition is derived from a DE 9.0-12.0 maltodextrin, which is the naturally derived hydroxyl containing chain transfer agent.
• a DE of 9.0-12.0 roughly corresponds to a glucose degree of polymerization of 10-13, or a number average molecular weight (Mn) of 1600-2100.
• the amount of the hybrid copolymer composition derived from maltodextrin was 50 wt.% (based on dry polymer). A critical feature of this synthesis is that a maltodextrin with a DE>5 was used.
• the maltodextrin solution was added rapidly to the reaction flask monomer/initiator in reactor. Heating of the reaction mixture was then begun using a water bath (hot-plate controlled by Thermo-watch controlled via bath thermometer). The reaction temperature was brought to 70 ⁇ 1 °C° under a positive pressure of nitrogen. A ⁇ 3 °C exotherm was noted during the initial 3 ⁇ 4 Hr of reaction, after which the reaction and bath temperatures became almost equal.
• the reaction was held at 70 °C for a total of 10 h (over two days). At the conclusion of the polymerization, the reaction was cooled to ambient temperature with a cold water bath, the amount of water that was found to be lost (2.18 g) was replenished.
• the polymer solution as prepared was not transparent.
• the polymer solution was diluted from 30.3% solids (in theory) to 20% solids (in theory by the addition of water, but the solution was still not clear. Further dilution to a theoretical polymer concentration of 18 wt.% resulted in an essentially transparent solution. A total of 279.58g extra water was needed to dilute the polymer.
• the yield of polymer solution was 697.9 g.
• the experimental solids was 17.9%. This corresponds to a monomer conversion of 99.4.
• the final product was preserved by the addition of 0.75 wt% Glydant Plus on total solution weight; final polymer solution solids were 18.47 %.
• maltodextrin as a polysaccharide chain transfer agent (STAR-DRI 180 DE 18 spray- dried maltodextrin available from Tate and Lyle, Decatur, Illinois) was dissolved in 150 grams of water in a reactor and heated to 75°C.
• An initiator solution comprising of 6.6 grams of sodium persulfate in 40 grams of water was added to the reactor at the same time as the monomer solution over a period of 90 minutes.
• the reaction product was held at 98°C for an additional 60 minutes.
• the reaction product was then neutralized by adding 14 grams of a 50% solution of NaOH and the final product was an amber colored solution.
• An initiator solution comprising of 0.2 grams of sodium persulfate in 20 grams of water was added to the reactor at the same time as the monomer solution over a period of 35 minutes.
• the reaction product was held at 98°C for an additional 2 hours.
• the final product was a slightly opaque yellow colored solution.
• the reaction was diluted with 30 grams of water and the temperature was lowered to 72 to 75°C.
• a solution of 80.7 grams of dimethyl diallyl ammonium chloride (62% in water) was added to the reactor over a period of 30 minutes.
• An initiator solution comprising of 0.2 grams of sodium persulfate in 20 grams of water was added to the reactor at the same time as the monomer solution over a period of 35 minutes.
• the reaction product was held at 98°C for an additional 2 hours.
• the final product was a clear light yellow colored solution.
• Carboxymethyl cellulose (AQUALON® CMC 9M3ICT available from Hercules, Inc., Wilmington, Delaware) was depolymerized in the following manner. Thirty grams of
• AQUALON® CMC was introduced in to 270 g of deionized water with stirring. 0.03 g of Ferrous ammonium sulfate hexahydrate and 2 g of hydrogen peroxide (H2O2) solution (35% active) was added. The mixture was heated to 60° C and held at that temperature for 30 minutes. This depolymerized CMC solution was then heated to 90 0 C.
• H2O2 hydrogen peroxide
• a monomer solution containing 50 grams of acrylamide (50% solution) is subsequently added to the reactor over a period of 50 minutes.
• An initiator solution comprising of 2 grams of V-086 2,2'-Azobis [2-methyl-N-(2-hydroxyethyl) propionamide] azo initiator from Wako Pure Chemical Industries, Ltd., Richmond, Virginia] in 30 grams of water is added to the reactor at the same time as the monomer solution over a period of 60 minutes. The reaction product is held at 90°C for an additional 60 minutes.
• gelatinization was completed.
• the reaction was diluted with 30 grams of water and the temperature was lowered to 72 to 75°C.
• a solution of 100.1 grams of [3- (methacryloylamino)propyl]-trimethylammonium chloride (50% in water) was added to the reactor over a period of 30 minutes.
• An initiator solution comprising of 0.2 grams of sodium persulfate in 20 grams of water was added to the reactor at the same time as the monomer solution over a period of 35 minutes.
• the reaction product was held at 98°C for an additional 2 hours.
• the final product was an opaque white homogenous solution.
• the reaction was diluted with 30 grams of water and the temperature was lowered to 72 to 75°C.
• a solution of 66.71 g [2-(methacryloxy)ethyl]-trimethylammonium chloride (75% in water) was added to the reactor over a period of 30 minutes.
• An initiator solution comprising of 0.2 grams of sodium persulfate in 20 grams of water was added to the reactor at the same time as the monomer solution over a period of 35 minutes.
• the reaction product was held at 98°C for an additional 2 hours.
• the final product was a homogeneous opaque white paste.
• Hydroxy ethyl cellulose (QP 300 available from Dow) was depolymerized in the following manner. Thirty grams of QP 300 was introduced in to 270 g of deionized water with stirring. 0.05 g of Ferrous ammonium sulfate hexahydrate and 1 g of hydrogen peroxide (H2O2) solution (35%) active) was added. The mixture was heated to 60° C and held at that temperature for 30 minutes. This depolymerized CMC solution was then heated to 90 0 C.
• H2O2 hydrogen peroxide
• a solution of 38.7 grams of dimethyl diallyl ammonium chloride (62% in water) is subsequently added to the reactor over a period of 50 minutes.
• An initiator solution comprising of 2 grams of V-086 2,2'-Azobis [2-methyl-N-(2-hydroxyethyl) propionamide] azo initiator from Wako Pure Chemical Industries, Ltd., Richmond, Virginia] in 30 grams of water is added to the reactor at the same time as the monomer solution over a period of 60 minutes. The reaction product is held at 90°C for an additional 60 minutes.
• An initiator solution comprised of 13.84 grams of erythorbic acid dissolved in 100 grams of water, and a second initiator solution comprised of 13.98 grams of tert- butyl hydrogen peroxide were added to the reactor at the same time as the monomer solution over a period of 5 hours.
• the reaction product was cooled and held at 65°C for an additional 60 minutes.
• the final product was a brown solution.
• a second initiator solution comprising of 21 grams of a 70% solution of tertiary butyl hydroperoxide dissolved in 109 grams of water was added over a period of 5.5 hours.
• the reaction product was held at 87°C for 30 minutes.
• the final product was a clear light amber solution and had 34.1% solids.
• N- vinyl pyrrolidone / maltodextrin (DE 13.0-17.0) hybrid mixture The synthetic component of the hybrid copolymer composition is derived from N- vinyl pyrrolidone; the naturally occurring portion of the hybrid copolymer composition is derived from a DE 13.0-17.0 maltodextrin, which is the naturally derived hydroxyl containing chain transfer agent.
• a DE of 13.0-17.0 roughly corresponds to a glucose degree of polymerization of 7-9, or a number average molecular weight (Mn) of 1100-1500.
• the amount of the hybrid copolymer composition derived from maltodextrin was 50 wt.% (based on dry polymer). A maltodextrin with a DE>5 was used.
• the reaction was warmed to 80 °C using an oil bath and 1 ⁇ 4 of the contents of the addition funnel were added at once. Heating was continued, and when the temperature reached 95 °C, drop-wise addition at a uniform rate over 3 h. of the contents of the addition funnel was commenced. After the addition was complete, heating at 95 °C was continued for an additional 2.75 h. At the conclusion of the reaction, the polymer solution was clear with some viscosity build.
• the experimental solids (gravimetric at 130 °C for 1.5 h, duplicate runs) was 30.4%.
• the polymer was preserved by the addition of 0.75 wt.% Glydant Plus.
• the synthetic component of the hybrid copolymer composition is derived from a combination of N- vinyl pyrrolidone and vinyl caprolactam; the naturally occurring portion of the hybrid copolymer composition is derived from a DE 13.0-17.0 maltodextrin, which is the naturally derived hydroxyl containing chain transfer agent.
• a DE of 13.0-17.0 roughly corresponds to a glucose degree of polymerization of 7-9, or a number average molecular weight (Mn) of 1100-1500.
• the amount of the hybrid copolymer composition derived from maltodextrin was 50 wt.% (based on dry polymer). A maltodextrin with a DE>5 was used.
• Flask Flask
• Addition funnel #1 N- vinyl pyrrolidone (Aldrich) 30.05 g
• 2,2'-Azobis[2-methyl-N-(2-hydroxyethyl)propionamide] (Wako VA-086) 0.6085 g
• a four-neck round 1000 mL bottom flask was equipped with a mechanical stirrer, reflux condenser, 125 mL addition funnel, and a 250 mL addition funnel.
• To the flask were charged 56.48 g deionized water and 63.72 g maltodextrin Maltrin Ml 50 (DE 13.0-17.0). The mixture was stirred with gentle heating until a homogeneous solution was obtained.
• Addition Funnel #1 was charged with a mixture of 30.05 g N-vinyl pyrrolidone and 30.41 g N-vinyl caprolactam (homogeneous solution).
• Addition Funnel #2 was charged with a solution of 0.6085 g 2,2'-Azobis[2-methyl-N-(2-hydroxyethyl)propionamide] (Wako VA-086) in 135.00 g deionized water.
• the reaction was warmed to about 75 °C using a thermostatted oil bath. At this point, 1 ⁇ 4 of the contents of each addition funnel was added at once. The solution in the flask became cloudy - it was no longer homogeneous. Heating of the reaction vessel was continued, and when the reaction temperature reached 96 °C, drop-wise addition of the contents of the two addition funnels over a period of 3 h. was commenced. The rate of addition was fairly uniform although adjustments to the rate were occasionally necessary to stay on target for a 3 h. addition time; the reaction temperature was maintained at 96-99 °C throughout the polymerization. The reaction mixture remained cloudy throughout the polymerization, and there appeared to be a formation of distinct phases. After the addition was complete, heating was continued for an additional 0.5 h. At the conclusion of the reaction, the polymer solution was cloudy.
• the polymer solution was preserved by the addition of 0.75 wt.% Glydant Plus.
• Cloud point at 1 wt.% in water (heating rate ⁇ 2 °C/minute): 77 °C.
• the synthetic component of the hybrid copolymer composition is derived from a combination of N- vinyl pyrrolidone and vinyl caprolactam; the naturally occurring portion of the hybrid copolymer composition is derived from a DE 13.0-17.0 maltodextrin, which is the naturally derived hydroxy 1 containing chain transfer agent.
• a DE of 13.0-17.0 roughly corresponds to a glucose degree of polymerization of 7-9, or a number average molecular weight (Mn) of 1100-1500.
• the amount of the hybrid copolymer composition derived from maltodextrin was 50 wt.% (based on dry polymer). A maltodextrin with a DE>5 was used.
• a four- neck round 1000 mL bottom flask was equipped with a mechanical stirrer, a nitrogen inlet topped reflux condenser, 125 mL addition funnel, and a 250 mL addition funnel.
• a mechanical stirrer to the flask were charged 56.24 g deionized water and 63.75 g maltodextrin Maltrin Ml 50 (DE 13.0-17.0). The mixture was stirred with gentle heating until a homogeneous solution was obtained.
• Addition Funnel #1 was charged with 60.22 g of a 50/50 (w/w) mixture of N-vinyl pyrrolidinone and N-vinyl caprolactam (homogeneous solution).
• Addition Funnel #2 was charged with a solution of 0.6130 g 2,2'-Azobis(2-methylpropionamidine)dihydrochloride (Wako V-50) in 135.03 g deionized water.
• the contents of the flask, Addition funnel #1, and Addition Funnel #2 were deoxygenated by sub-surface purging with nitrogen for 15, 5, and 5 minutes, respectively.
• the reaction was warmed to about 70 °C using a thermostatted oil. At this point, 1 ⁇ 4 of the contents of each addition funnel was added at once. The solution in the flask became hazy - it was no longer homogeneous. Drop-wise addition of the contents of the two addition funnels over a period of 3 h. was then commenced. The rate of addition was fairly uniform although adjustments to the rate were occasionally necessary to stay on target for a 3 h. addition time. The reaction temperature was maintained at 65-71 °C throughout the polymerization, and the polymerization was kept under a positive pressure of nitrogen throughout. The reaction mixture remained cloudy throughout the polymerization, and there appeared to be a formation of distinct phases. After the addition was complete, heating was continued for an additional 3 h. At the conclusion of the reaction, the polymer solution was frothy, white (cloudy), and viscous.
• the reaction was diluted to 400 g total by the addition of 90.9 g deionized water, but it did not fully clear. An additional 75.27 g deionized water was added; the reaction was nearly clear at this point and apparently homogeneous.
• the yield of polymer solution measured in the flask was 475.27 g.
• the experimental solids (gravimetric at 130 °C for 1.5 h; average of two runs) was 24.9%.
• the polymer solution was preserved by the addition of 0.57 wt.% Glydant (solid).
• Cloud point at 1 wt.% in water was 58 °C.
• the synthetic component of the hybrid copolymer composition is derived from vinyl caprolactam; the naturally occurring portion of the hybrid copolymer composition is derived from a DE 13.0-17.0 maltodextrin, which is the naturally derived hydroxyl containing chain transfer agent.
• a DE of 13.0-17.0 roughly corresponds to a glucose degree of polymerization of 7-9, or a number average molecular weight (Mn) of 1100-1500.
• the amount of the hybrid copolymer composition derived from maltodextrin was 50 wt.% (based on dry polymer). A maltodextrin with a DE>5 was used.
• the polymer was prepared according to the method described in Synthesis Example 22 with the following exceptions. 4,4'-Azobis(4-cyanovaleric acid), 0.5 parts per hundred parts monomer and maltodextrin combined(pphm), neutralized to pH 7 with sodium hydroxide, was used as the initiator, and the reaction was post-treated with 0.2 pphm 4,4'-Azobis(4-cyanovaleric acid), neutralized to pH 7 with sodium hydroxide for 5 h at reflux after dilution of polymer solids to 20 wt.%). The yield of homogenous polymer solution was 703.4 g. The solids were 19.1%.
• the synthetic component of the hybrid copolymer composition is derived from vinyl caprolactam N-vinyl pyrrolidone; the naturally occurring portion of the hybrid copolymer composition is derived from glucose, which is the naturally derived hydroxyl containing chain transfer agent.
• the polymer is prepared according to the method described in Synthesis Example 22. SYTHESIS EXAMPLE 27
• the synthetic component of the hybrid copolymer composition is derived from vinyl caprolactam N-vinyl pyrrolidone; the naturally occurring portion of the hybrid copolymer composition is derived from lactose, which is the naturally derived hydroxyl containing chain transfer agent.
• the polymer is prepared according to the method described in Synthesis Example 22.
• the synthetic component of the hybrid copolymer composition is derived from N-vinyl pyrrolidone; the naturally occurring portion of the hybrid copolymer composition is derived from a DE 4.0-7.0maltodextrin, which is the naturally derived hydroxyl containing chain transfer agent.
• a DE of 4.0-7.0 roughly corresponds to a glucose degree of polymerization of 17 to 30, or a number average molecular weight (Mn) of 2800 to 4900.
• the amount of the hybrid copolymer composition derived from maltodextrin was 50 wt.% (based on dry polymer). A maltodextrin with a DE of about 5 was used.
• a four-neck round bottom flask was equipped with a mechanical stirrer, reflux condenser, a 60 mL addition funnel and a 125 mL addition funnel.
• the weight of the flask with stirring apparatus alone was 467.74 g.
• To the flask were charged 57.12 g of deionized water and 26.3804 g Maltrin M040.
• the resulting mixture was heated using a thermostatted oil bath to -90 °C at which point the maltodextrin slowly dissolved to give a clear, slightly viscous solution.
• Theoretical solids of the polymer solution (based on the amount of monomer and maltodextrin added divided by the total yield of polymer solution): 20.0%.
• the experimental solids (gravimetric at 130 °C for 1.5 h) was 20.0%. This corresponds to a monomer conversion of essentially 100%.
• the synthetic component of the hybrid copolymer composition is derived from N-vinyl pyrrolidone; the naturally occurring portion of the hybrid copolymer composition is derived from a DE 4.0-7.0 maltodextrin, which is the naturally derived hydroxyl containing chain transfer agent.
• a DE of 44.0-7.0 roughly corresponds to a glucose degree of polymerization of 17 to 30, or a number average molecular weight (Mn) of 2800 to 4900.
• the amount of the hybrid copolymer composition derived from maltodextrin was 25 wt.% (based on dry polymer). A maltodextrin with a DE of about 5 was used.
• a four-neck round bottom flask was equipped with a mechanical stirrer, reflux condenser, a 125 mL addition funnel, and a stopper.
• the weight of the flask with stirring apparatus alone was 471.62 g.
• To the flask were charged 13.1807 g Maltrin M040 (DE 5 maltodextrin) and 28.84 g deionized water.
• the mixture was heated to ⁇ 90 °C with stirring until a clear, homogeneous solution was obtained.
• the mixture was allowed to cool somewhat after it became clear, but it did not drop below 50 °C.
• the resulting mixture was stirred and warmed to 95 °C using a thermostatted oil bath. When the temperature reached 93 °C, drop-wise addition over 3 h of the contents of the addition funnels was commenced. The rate of addition was fairly uniform throughout. During the course of the addition viscosity was noted to increase, and the reaction mixture gradually changed from clear to hazy. After the addition was complete, heating at 95 °C was continued for an additional 3 h. One hour after the addition was complete, 29.17 mL deionized water was added drop- wise to the reaction via the addition funnel while the reaction temperature was maintained at 95 °C. The polymerization reaction mixture remained hazy after the addition of the water. After heating was stopped, the reaction became quite turbid.
• a solution of the polymer to be evaluated was prepared at the desired concentration
• the temperature of the pressure cell was then lowered from 20.5°C to 1°C over 18.97 hours at a constant cooling rate by circulating cooling/heating fluid through the cell jacket while stirring at 600 rpm.
• the actual pressure of the cell and the temperature were monitored during the cooling.
• the time and temperature at which the measured pressure began to deviate from the expected pressure were taken to be the gas hydrate formation onset time and temperature.
• the rapid hydrate formation time and temperature were taken to be the point at which the temperature of the cell contents began to increase due to the exothermic hydrate formation process. This is illustrated for the hybrid mixture of Synthesis Example 24, as shown in the Figure.
• the inventive polymers lowered both the Onset Temperature and Rapid Hydrate Formation Temperature compared to when no polymer was added and increased the Onset Time and Rapid Hydrate Formation Time compared to when no polymer was added.
• the inventive polymers compared favorably to the commercial kinetic gas hydrate inhibitor polymer with respect to the Onset Time and Rapid Hydrate Formation Time.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Life Sciences & Earth Sciences (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Materials Engineering (AREA)
• Health & Medical Sciences (AREA)
• Public Health (AREA)
• Water Supply & Treatment (AREA)
• Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

Priority Applications (1)

Applications Claiming Priority (4)

Publications (1)

Family

ID=45401091

Family Applications (1)

Country Status (3)

Families Citing this family (3)

Family Cites Families (5)

• 2011
  • 2011-12-23 US US13/997,338 patent/US20130292611A1/en not_active Abandoned
  • 2011-12-23 WO PCT/EP2011/073928 patent/WO2012089654A1/en active Application Filing
  • 2011-12-23 EP EP11799728.8A patent/EP2658945A1/de not_active Withdrawn

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events