Classifications

• • 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
  • C09K8/02—Well-drilling compositions
  • C09K8/03—Specific additives for general use in well-drilling compositions
  • C09K8/035—Organic additives
• • 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
  • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
  • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
  • C08F220/52—Amides or imides
  • C08F220/54—Amides, e.g. N,N-dimethylacrylamide or N-isopropylacrylamide
  • C08F220/58—Amides, e.g. N,N-dimethylacrylamide or N-isopropylacrylamide containing oxygen in addition to the carbonamido oxygen, e.g. N-methylolacrylamide, N-(meth)acryloylmorpholine
  • C08F220/585—Amides, e.g. N,N-dimethylacrylamide or N-isopropylacrylamide containing oxygen in addition to the carbonamido oxygen, e.g. N-methylolacrylamide, N-(meth)acryloylmorpholine and containing other heteroatoms, e.g. 2-acrylamido-2-methylpropane sulfonic acid [AMPS]
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S507/00—Earth boring, well treating, and oil field chemistry
  • Y10S507/935—Enhanced oil recovery
  • Y10S507/936—Flooding the formation

Definitions

• the present invention relates to certain new polymers which provide significantly improved water retention of the drilling fluids, i.e. the presence of which significantly reduces the tendency of the drilling fluid to release filtrate into the formation. Compared to the currently Available drilling fluid additives, the polymers according to the invention have a considerably superior calcium tolerance and thermal stability.
• the present invention thus relates to water-soluble copolymers which are composed of
• crosslinking agents which contain at least two olefinic double bonds in the molecule, where R 1 or R 2 independently of one another are hydrogen, methyl or ethyl or together trimethylene or pentamethylene,
• R3 and R 5 are hydrogen or methyl; R 4 imidazole- (1) or imidazole- (2) and
• R 6 is hydroxy, alkoxycarbonyl with 1 to 12 carbon atoms in the alkoxy group, cycloalkoxycarbonyl with 6 to 10 carbon atoms in the cycloalkoxy group, phenyl, alkanoyloxy with 1 to 4 carbon atoms or ß-hydroxyalkoxycarbonyl with 2 or 3 carbon atoms in the Hydroxy-alkoxy group mean.
• Y stands for a simple covalent bond or a group of the formula -CON-C (CH 3 ) 2 -CH 2 - and x + stands for a cation.
• the present invention also relates to water-soluble copolymers which are composed of 1 a) 1 to 95 wt. % Assemblies of formula Ib
• Preferred copolymers according to the invention are composed of 20 to 80% by weight of assemblies of the formula I, 0 to 15% by weight of assemblies of the formula II, 0 to 40% by weight of assemblies of the formula III, 0 to 20% by weight of assemblies of the formula V. and 5 to 50% by weight of components of the formula IV in which R4 is an imidazolyl (1) radical.
• Copolymers according to the invention which contain an assembly, the proportion of which can also be O by definition, are preferred if the proportion of these assemblies is at least 1% by weight.
• copolymers according to the invention are particularly preferred in which several of the preferred features mentioned above are combined.
• the alkyl unit of the alkoxycarbonyl group of R 6 can, for example, be one of the groups methyl, ethyl, propyl, isopropyl, n-butyl- (1), n-butyl- (2), isobutyl, tert-butyl, amyl, neopentyl, hexyl, 2 -Ethyl-hexyl- (1), octyl, dodecyl and it can be linear or branched with the appropriate chain length.
• Examples of the cycloalkyl unit of a cycloalkoxycarbonyl group representing R 6 are the monocyclic cyclohexyl group or polycyclic groups, such as, for example, boryl, isobornyl, norbornyl and derivatives of such terpenes.
• Examples of the ⁇ -hydroxyalkyl unit in the substituent R 6 are ⁇ -hydroxyethyl, 2-hydroxypropyl- (1) or 1-hydroxypropyl- (2).
• the cation X + can in principle be derived from any known water-soluble base which is strong enough to neutralize the sulfonic acid and which does not impair the water-solubility of the copolymer.
• the selection can thus be made in a simple known manner, in particular X + can be an alkali metal cation, preferably a sodium or potassium cation or an ammonium cation of the formula [HNR 3 7 ] + .
• the three R 7 radicals can be the same or different and denote hydrogen, alkyl having 1 to 4 carbon atoms or hydroxyethyl.
• the present invention also relates to partial hydrolysis of the copolymers defined above.
• partial hydrolysis of the copolymers according to the invention up to 60%, preferably 10 to 30%, of the amide functions of the assemblies of the formula III and of the ester functions in the assemblies of the formula V can be converted into carboxyl functions, as a result of which the above-mentioned assemblies in those of formula VI (VI)
• R 3 and X + have the meanings given above.
• the excellent dispersion stabilization and viscosity increase of the polymers according to the invention and their partial hydrolyzates in concentrated salt solutions as well as their temperature stability can be further improved by the presence of basic groups, i.e. those that are able to add proton.
• copolymers according to the invention are hydrolyzed which contain components of the formula II. Depending on the conditions of the partial hydrolysis, these assemblies can be hydrolyzed to a certain degree, and after the acyl residues -COR 2 have been split off, free amido groups -NHR 1 appear on the polymer chains, which show the above-mentioned basic reaction.
• the copolymers according to the invention can of course also include several different individuals in the molecule from each of the structural groups defined by the general formulas I to VI, which differ in the meanings of the symbols Y or R 1 and R 2 or R 3 and R 5 or R 4 or R 6 , contain. For example, in the same polymer molecule, they can contain both AIBS and vinylsulfonic acid building blocks or ring-open as well as ring-closed ones
• the copolymers according to the invention from the individual groups of the general formulas I to VI contain no more than three, preferably no more than two different individuals and, if appropriate, the crosslinking agent.
• Preferred crosslinkers which contain at least two olefinic double bonds in the molecule are divinyl benzene, methylene-bis-acrylamide, tetraallyloxetane, hexaallyl sucrose and triallyl isocyanurate.
• DBP 1 101 760 describes a process for the preparation of water-soluble copolymers from vinylsulfonic acid and acrylonitrile or methacrylonitrile, optionally in a mixture with other ethylenically unsaturated compounds.
• Copolymers of vinyl or alkyl sulfonates with acrylamide and vinyl amides have been described, for example, in DAS 2 444 108.
• AIBS 2-acrylamido-2-methyl-propanesulfonic acid- (3)
• Copolymers of vinylsulfonic acid, vinylimidazole, acrylic acid, butyl methacrylate and methacrylamide are to be used as casein substitutes in paper production according to DE-OS 2 457 117.
• a copolymer of vinylimidazole, acrylamide and acrylic acid in a molar ratio of 5: 90: 5 can be used as a desensitizer of photographic emulsions.
• the preparation of vinylimidazole / acrylic acid copolymers is, for example, from "Macromolecules" (1973), 6 (2), pages 163-168 and from J. Am. Soc, Div. Polym. Chem. (1972) 13 (1), pp. 364-368, and their use as binders for photoemulsions are known from FR patent application 2 182 170.
• the production of vinylimidazole / acrylamide copolymers by suspension polymerization is known from DE-OS 20 09 218 and the use of such copolymers in the production of offset printing plates from DE-OS 21 65 358.
• copolymers according to the invention insofar as they contain copolymerized comonomers of the formula II in which R 1 and R 2 together mean trimethylene, can be reacted in the manner known from the prior art, for example according to the information in US Pat. No. 3,929,741 the monomers at temperatures of about 10 to 120 ° C; preferably at 40 to 80 ° C, in the presence of suitable polymerization catalysts.
• the copolymers according to the invention contain radicals of the formula in which R 1 and R 2 do not jointly mean trimethylene or pentamethylene, it is necessary to convert the acidic components vinylsulfonic acid and AIBS into the salts with the cation ⁇ + before the polymerization by adding bases .
• the bases expediently used here are the hydroxides or salts of the cations X + with weak acids, such as, for example, carbonic acid or phosphoric acid, or, in the case of amine bases, NH 3 or the free amines.
• -CH 2 CH-N-CO-R 2 (Ha) in which R 1 and R 2 are identical or different and are hydrogen, methyl or ethyl or together are trimethylene or pentamethylene and, if appropriate, 0 to 80 parts by weight of acrylamide and / or methacrylamide, 0 to 50% by weight of a comonomer of the formula Va
• R 5 -CH 2 CR 6 (Va), where the symbols R 5 and R 6 have the meanings given above, and, if appropriate, 0 to 25% by weight of a crosslinking which comprises at least two, olefi
• the copolymerization is then initiated in a manner known per se and carried out at 10 to 120 ° C.
• Preferred copolymers according to the invention are obtained when 20 to 80% by weight of the olefinically unsaturated sulfonic acid of the formula Ia, O to 15% by weight of the vinyl acylamine of the formula Ha, 0 to 40% by weight of acrylamide and / or methacrylamide are used to prepare the copolymer , 5 to 50 parts by weight of vinylimidazole, 0 to 10% by weight of the comonomer of the formula Va and, if appropriate, 0 to 25% by weight of the crosslinking agent.
• the polymerisation can be carried out as solution polymerisation, as precipitation polymerisation or in reverse emulsion, e.g. according to the information given in German patent 1,089,173.
• the polymerization proceeds under the conditions of the solution polymerization , and a viscous aqueous or aqueous / alkanolic solution of the copolymer according to the invention is obtained, from which the product can be isolated by distilling off the solvent or precipitation by mixing the solution with a water-miscible organic solvent, such as methanol, ethanol, acetone or the like.
• a water-miscible organic solvent such as methanol, ethanol, acetone or the like.
• the aqueous or aqueous alkanolic solution obtained is preferably fed to the intended use directly, possibly after setting a desired concentration.
• a water-miscible organic solvent When carrying out the copolymerization in a water-miscible organic solvent, one works under the conditions of the precipitation polymerization.
• the polymer precipitates directly in solid form and can be isolated by distilling off the solvent or else by suction and drying.
• Water-miscible organic solvents which are suitable for carrying out the production process according to the invention are, in particular, water-soluble alkanols, namely those having 1 to 4 carbon atoms, such as methanol, ethanol, propanol, isopropanol, n-, sec- and isobutanol, but preferably tert-butanol.
• the water content of the lower alkanols used as solvents should not exceed 6% by weight, since otherwise a lump formation can occur during the polymerization.
• the water content is preferably 0-3%.
• the amount of solvent to be used depends to a certain extent on the type of comonomers used.
• the aqueous monomer solution is known in a known manner in an water-immiscible organic solvent such as cyclohexane, toluene, xylene, heptane or still boiling gasoline fractions with the addition of 0.58%, preferably 1-4% W / O type emulsifiers, emulsified and polymerized with conventional free-radical initiators.
• the initiator can be both water-soluble in nature and is then dissolved in the monomer solution, but it can also be oil-soluble and in this case is added to the finished W / O emulsion or the oil phase.
• a more detailed description of the method can be found, for example, in German Patent 1,089,173.
• the copolymers according to the invention are optionally still partially saponified.
• any water-soluble base whose strength is sufficient for a reaction with the hydrolyzable groups can be used as the saponification agent.
• NaOH, KOH, NH 3 or neutral or acidic alkali (especially sodium and potassium) and ammonium salts of carbonic acid, boric acid and phosphoric acid are preferred.
• the saponification agent is either already added to the monomer solution or mixed with the polymer. Depending on the procedure, the saponification therefore takes place already during the normally exothermic polymerization or by further supply of heat after the polymerization. A combination of both procedures is also possible.
• Preferred copolymers according to the invention and to be used according to the invention with a particularly high degree of polymerization are obtained if the polymerization is carried out in aqueous solution by the so-called gel polymerization method. 15-50% aqueous solutions of the comonomers are known to be suitable
• High-energy electromagnetic radiation or the usual chemical polymerization initiators can be used to initiate the polymerization, e.g. organic peroxides, such as benzoyl peroxide, tert-butyl hydroperoxide, methyl ethyl ketone peroxide, cumene hydroperoxide, azo compounds such as azo-di-iso-butyro-nitrile or 2,2'-azo-bis (2-amiöino ⁇ ropan) dihydrochloride
• HN -C (CH 3 ) 2 -N- NC (CH 3 ) 2 - NH. 2 HCl NH 2 NH 2 and inorganic peroxy compounds such as
• reducing agents such as sodium hydrogen sulfite and iron (II) sulfate or redox systems which, as a reducing component, contain an aliphatic and aromatic sulfinic acid, such as benzenesulfin contain acid and toluenesulfinic acid or derivatives of this acid, such as Mannich adducts of sulfinic acid, aldehydes and amino compounds, as described in German Patent 1,301,566.
• 0.03 to 2 g of the polymerization initiator are used per 100 g of total monomers.
• the quality properties of the polymers can be improved further by reheating the polymer gels obtained by the gel polymerization process in the temperature range of 50-130 ° C., preferably 70-100 ° C. for several hours.
• copolymers according to the invention prepared in this way in the form of aqueous jellies, can, after mechanical comminution, be dissolved directly in water using suitable apparatus and used. However, they can also be obtained in solid form by known drying processes after removal of the water and can only be dissolved in water again when they are used.
• copolymers according to the invention are outstandingly suitable as auxiliaries in drilling fluids. They show a very good protective colloid effect both at high. Temperatures as well as at high electrolyte concentrations and are, in particular with regard to electrolyte stability and heat and aging resistance, considerably superior to the closest comparable drilling fluid additives known from US Pat. No. 2,775,557 and DTPS 1,300,481 and 2,444,108.
• the products according to the invention have a further improved combination of valuable application properties, which are particularly advantageous when used for particularly critical drilling tasks under difficult conditions at great depths and in the presence of formation water with a very high electrolyte content.
• the polymers according to the invention are also characterized in particular by stability to 10-40% mineral acids such as HCl, HNO 3 , H 2 SO 4 , HCIO 4 and so on, and also to organic acids such as HCOOH and CH 3 COOH. No precipitation occurs even if the acidic solutions are stored for several hours.
• the copolymers according to the invention are therefore also outstandingly suitable as thickeners for acids.
• the copolymers according to the invention are used in concentrations of 0.5 to 40 kg / m ⁇ , preferably 3 - 30 kg / m ⁇ .
• the aqueous drilling fluids mainly contain bentonites to increase the viscosity and seal through pierced formations. Shear spar, chalk and iron oxides are added to increase the density of the drilling mud.
• Bentonite, heavy spar, chalk and iron oxide can be added to the drilling fluids alone or in a wide variety of mixing ratios.
• the upward limiting factor is the rheological properties of the drilling mud.
• copolymers according to the invention are added to conventional deep drilling cement slurries, products with considerably improved flow and setting properties are obtained.
• VA N-vinylacetamide AM: acrylamide
• VMA N-vinyl-N-methyl-acetamide
• AIBS 2-acrylamido-2-methyl-propanesulfonic acid- (3) being the high number
• VIM l-vinylimidazole
• VPYR N-vinyl pyrrolidone
• VCAP N-vinyl caprolactam
• VSS-Na vinyl sulfonic acid Na salt
• PVA polyvinyl alcohol
• TMPTA trimethylolpropane triacrylate
• K values given in the following examples are the K values according to Fikentscher, "cellulose chemistry”. Vol. 13, page 58 (1932).
• the mixture is heated for a further 2 hours at 80 ° C., forming a viscous suspension.
• the polymer can be isolated by suction and drying under vacuum at 50 ° C. However, the solvent can also be distilled off directly from the reaction mixture under reduced pressure.
• the polymer is obtained in the form of a white, light powder which dissolves well in water. K value according to Fikentscher 195.
• the copolymer seeds of Table 1 can also be prepared.
• Example 1 In the apparatus described in Example 1 540 g of water and 20 g of 25% solution of vinyl sulfonic acid Na salt are initially introduced and 60 g of AIBS are dissolved therein. The solution is adjusted to a pH of 9.0 by adding 42.7 g of 27% strength aqueous sodium hydroxide solution. After adding 10 g of 1-vinylimidazole, 10 g of VMA and 15 g of acrylamide, the solution is heated to 60 ° C. while stirring and introducing a weak stream of N 2 . At this temperature, the polymerization is initiated by adding a solution of 0.5 g azoisobutyronitrile in 2.5 g dirnethylformamide. After an induction period of approx.
• Induction period of about 50 minutes sets in and the temperature rises to about 84 ° C over about 60 minutes.
• the mixture is heated for a further 2 hours at 80 ° C.
• a slightly cloudy, yellow-brown gel which can be cut after cooling and has a K value of 215 according to Fikentscher is obtained.
• the polymer can also be converted into readily water-soluble powder form, for example in such a way that the gel is mechanically reduced in size, dried - for example by freeze-drying or drying at an elevated temperature - and then in a known manner, for example using an oscillating mill, to give a fine powder grinds.
• the monomers specified in Table I were copolymerized in accordance with the instructions of Example 1.
• the monomers of Examples 12-14 were copolymerized according to Example 2.
• Solution II is now emulsified in solution I at room temperature, then the emulsion is flushed with nitrogen for 30 minutes with thorough stirring and finally heated to 60 ° C. As soon as this temperature is reached, a solution of 25 ml of dicyclohexyl peroxidicarbonate in 0.5 ml of toluene is injected, then the heating bath is removed and the stirring speed is reduced to 100 rpm. The internal temperature rises to 78 ° C within a few minutes (T. max.), At the same time the emulsion becomes increasingly transparent. After the main reaction has subsided, the mixture is heated for a further 30 minutes at 70 ° C. and then allowed to cool to room temperature.
• a storage-stable, low-viscosity W / O emulsion with a polymer content of 30% is obtained.
• the copolymer can be obtained in bulk by pouring the present emulsion into an excess of acetone.
• the copolymer precipitates and can be isolated, for example, by filtration, suction or centrifugation and, if appropriate, washing with acetone.
• the polymers can be isolated, as described above, by precipitation with a water-miscible solvent which dissolves the oil phase, preferably with acetone.
• Example 2 In the polymerization apparatus described in Example 1, 70 ml of water, 15 g of AIBS sodium salt, 3 g of 1-vinylimide azole and 1.5 g of polyvinyl alcohol, degree of hydrolysis 88%, are mixed and stirred until a clear solution is obtained. Then 3 g of IBOMA are dissolved in 30 ml of a technical
• Isoparaffin mixture with a boiling range of 200 to 240 ° C ( ® ISOPAR M) added.
• the two layers are stirred vigorously for two hours and the apparatus is flushed with nitrogen.
• 3.5 ml of an emulsifier (HLB 6-7) are added and the mixture is again stirred vigorously.
• 60 mg of 2,2'-azo-bis (2-amidinopropane) dihydrochloride is added as a radical-forming polymerization initiator.
• the reaction mixture is then gradually warmed to 60 ° C with slow stirring, giving a milky gel over two hours.
• the mixture is stirred for a further 16 hours at 60.degree. C. and the polymer is then converted into powder form according to Example 31.
• the K value of the product is 142.
• the copolymers of Table V below can also be prepared by the above process.
• each of the polymers from Table Va are added to a drilling fluid which consists of 350 ml synthetic seawater, 21 g attapulgite and 10 g illite and the pH of which has been adjusted to 9.5.
• the loss of liquid in the drilling mud mixtures thus obtained was immediately after the production (initial value) and measured after aging for 16 hours at 176.6 ° C at 190.5 ° C and 204.4 ° C.
• the initial water loss was 10.5 ml
• the value after 16 hours aging at 149 ° C was 19.5 ml.
• a drilling fluid is produced in the laboratory that contains 159 liters (one barrel) of synthetic seawater, 9.53 kg (21 pounds) of attapulgite clay and 4.54 kg (10 pounds) of illite clay.
• This drilling fluid has a high water loss. if you don't add polymers that reduce water loss.
• Samples of this drilling fluid were each mixed with one of the copolymers according to the invention specified above, namely in an amount corresponding to 1.81 kg (4 pounds) per 159 liters (one barrel) of the drilling fluid. Then the water loss of the drilling fluids thus obtained was measured. The measurement was carried out according to the well-known 30-minute water loss standard tests of the American Petroleum Institute. After the measurement, all Drill samples heated to a certain temperature for 16 hours and then the water loss test repeated.
• the polymers according to the invention bring about different degrees of improvement in the water retention capacity of the drilling fluids compared to known, commercially available polymers known for this purpose.
• the copolymers according to the invention also show improved heat stability of the water retention capacity compared to known products.
• the water loss of the drilling fluid not mixed with polymer is 98.0 ml, while after addition of the polymer from Example 4 in an amount corresponding to 1.81 kg per 159 1 drilling fluid, there is only a water loss of 9.5 ml.
• Drilling fluid with a water-soluble polyacrylate which is commercially available as an aid to reducing the water loss from drilling fluids ( ® CYPAN)
• the initial water loss is 8 ml
• the water loss after 16 hours of aging is 176.6 ° C and 58.0 ml
• copolymers according to the invention show outstanding cation tolerance towards divalent cations, especially against calcium. This is clear from Table VII below.
• Example 56 water loss measurements described in Example 56 were repeated with the difference that different amounts of calcium chloride were added to the drilling fluids.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Life Sciences & Earth Sciences (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=23325201

Family Applications (1)

Country Status (11)

Families Citing this family (61)

Family Cites Families (4)

• 1982
  • 1982-01-11 US US06/338,543 patent/US4471097A/en not_active Expired - Lifetime
  • 1982-12-14 EP EP83900030A patent/EP0111486A1/de not_active Withdrawn
  • 1982-12-14 BR BR8208082A patent/BR8208082A/pt unknown
  • 1982-12-14 JP JP83500140A patent/JPS58502213A/ja active Pending
  • 1982-12-14 AU AU10194/83A patent/AU1019483A/en not_active Abandoned
  • 1982-12-14 WO PCT/EP1982/000264 patent/WO1983002449A1/de not_active Application Discontinuation
• 1983
  • 1983-01-10 ZA ZA83134A patent/ZA83134B/xx unknown
  • 1983-01-11 IT IT19055/83A patent/IT1201961B/it active
  • 1983-08-22 FI FI832997A patent/FI832997A/fi not_active Application Discontinuation
  • 1983-08-26 NO NO833078A patent/NO833078L/no unknown
  • 1983-09-09 DK DK4111/83A patent/DK411183D0/da not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events