Aqueous polymer dispersions, a method for their preparation and the use thereof as pour-point depressants for crude oil, petroleum, and petroleum products

Abstract

The invention relates to aqueous polymer dispersions comprising at least one polymer obtainable by the reaction of at least one monomer M1 of the general formula (I): H.sub.2C═CH—C(O)OR, wherein R is an unbranched alkyl chain comprising from 18 to 22 carbon atoms, and optionally at least one monomer M2. The invention relates moreover to a method for the preparing of such aqueous polymer dispersion and the use thereof as pour point depressant for crude oil, petroleum, and petroleum products.

Claims

1. Aqueous polymer dispersion comprising water and a) 10 to 60% by weight based on the dispersion of at least one polymer P obtainable by the reaction of reactive monomers M, wherein the reactive monomers M consist of 50 to 100% by weight of at least one monomer M1 of the general formula (I)
H.sub.2C═CH—C(O)OR  (I) wherein R is an unbranched alkyl chain comprising from 18 to 22 carbon atoms; and 0 to 50% by weight of at least one monomer M2, which is different from monomer M1 and selected from the group consisting of acrylate monomers of the general formula (II),
H.sub.2C═CH—C(O)OR.sup.3  (II), wherein R.sup.3 is a branched or unbranched alkyl chain comprising from 1 to 12 carbon atoms, optionally substituted with a hydroxyl group; methacrylate monomers of the general formula (III)
H.sub.2C═C(CH.sub.3)—C(O)OR.sup.4  (III), wherein R.sup.4 is a branched or unbranched alkyl chain comprising from 1 to 12 carbon atoms, optionally substituted with a hydroxyl group; and vinylic aromatic monomers; wherein the amounts of the monomers M1 and M2 are each based on the total amount of all reactive monomers M used in the reaction, wherein the polymer P has a weight-average molecular weight M.sub.w of 20,000 to 150,000 g/mol according to DIN 55672-1:1995-02; and wherein the polymer P is present in the form of particles having an average particle size d.sub.50 of from 50 nm to 1000 nm effected by Column Hydrodynamic Chromatography; b) 5 to 60% by weight based on the total amount of the aqueous polymer dispersion of at least one water miscible solvent, c) 5 to 40% by weight based on the total amount of the aqueous polymer dispersion of at least one hydrophobic organic solvent, d) 0.1 to 20% by weight based on the total amount of the aqueous polymer dispersion of at least one ionic surfactant.

2. Aqueous polymer dispersion of claim 1, wherein the dispersion further comprises less than 10% by weight based on the total amount of monomers M of at least one protective colloid.

3. Aqueous polymer dispersion according to claim 1, wherein the at least one monomer M1 is a mixture, comprising 40 to 55% by weight, based on the total amount of monomers M1, of monomers M1 of formula (I), wherein R is an unbranched alkyl chain comprising 18 carbon atoms; 10 to 15% by weight, based on the total amount of monomers M1, of monomers M1 of formula (I), wherein R is an unbranched alkyl chain comprising 20 carbon atoms; and 35 to 45% by weight, based on the total amount of monomers M1, of monomers M1 of formula (I), wherein R is an unbranched alkyl chain comprising 22 carbon atoms.

4. Aqueous polymer dispersion according to claim 1, wherein the amount of the at least one monomer M2 is from 0 to 10% by weight based on the total amount of all reactive monomers M.

5. Aqueous polymer dispersion according to claim 1, wherein the at least one monomer M2 is selected from the group consisting of acrylate monomers of the general formula (II),
H.sub.2C═CH—C(O)OR.sup.3  (II), wherein R.sup.3 is a branched or unbranched alkyl chain comprising from 1 to 12 carbon atoms, optionally substituted with a hydroxyl group; methacrylate monomers of the general formula (III)
H.sub.2C═C(CH.sub.3)OR.sup.4  (III), wherein R.sup.4 is a branched or unbranched alkyl chain comprising from 1 to 12 carbon atoms, optionally substituted with a hydroxyl group.

6. Aqueous polymer dispersion according to claim 1, wherein the at least one monomer M2 is styrene, 2-ethylhexylacrylate, methylmethacrylate, 2-hydroxyethylmethacrylate or n-butyl acrylate.

7. Aqueous polymer dispersion according to claim 1, wherein the at least one water miscible solvent is a glycol.

8. Aqueous polymer dispersion according to claim 1, wherein the at least one hydrophobic organic solvent is an aromatic or aliphatic hydrocarbon or a mixture thereof.

9. Aqueous polymer dispersion according to claim 1, wherein the at least one ionic surfactant is anionic surfactant.

10. Aqueous polymer dispersion according to claim 1, wherein the at least one ionic surfactant is an anionic surfactant of formula (IV)
R.sup.5—O-(D).sub.1-(B).sub.m-(A).sub.n-XY.sup.−M.sup.+,  (IV) where R.sup.5 is a linear or branched, saturated or unsaturated, aliphatic and/or aromatic hydrocarbon radical having 8 to 30 carbon atoms, A is ethyleneoxy, B is propyleneoxy, and D is butyleneoxy, l is from 0 to 30, m is from 0 to 30 and n is from 0 to 30, X is (CH.sub.2).sub.a[C(O)].sub.b(CH.sub.2).sub.c, where a and c are independently from 0 to 4 and b 0 or 1; M.sup.+ is a cation, and Y.sup.− is SO.sub.3.sup.−, PO.sub.3.sup.2− or C(O)O.sup.−, where the A, B and D groups may be distributed randomly, alternatingly, or in the form of two, three, four or more blocks in any sequence, and wherein the sum of l+m+n is in the range from 0 to 30.

11. Aqueous polymer dispersion according to claim 10, wherein the at least one surfactant is an anionic surfactant of the general formula (IVa)
R.sup.5—O—(CH.sub.2CH.sub.2O).sub.nXY.sup.−  (IVa) wherein R.sup.5, n, X and Y.sup.− have the meaning as indicated in claim 10.

12. Aqueous polymer dispersion according to claim 10, wherein R.sup.5 is a linear, saturated and aliphatic hydrocarbon radical having 10 to 20 carbon atoms and/or 1 is 0 and/or m is 0 to 3 and/or n is 1 to 30 and/or XY is SO.sub.3.sup.−; PO.sub.3.sup.2− or C(O)CH.sub.2CH.sub.2C(O)O.sup.−.

13. Aqueous polymer dispersion according to claim 1, wherein the polymer P has a weight-average molecular weight M.sub.w of 20 000 to 100 000 g/mol.

14. Method for the preparation of the aqueous polymer dispersion claim 1, comprising the steps of a) preparation of an aqueous monomer dispersion comprising a1) 10 to 60% by weight based on the total amount of the resulting aqueous polymer dispersion of reactive monomers M, wherein the reactive monomers M consist of 50 to 100% by weight based on the total amount of the reactive monomers M of at least one monomer M1 of the general formula (I)
H.sub.2C═CH—C(O)OR  (I), and 0 to 50% by weight based on the total amount of the reactive monomers M of at least one monomer M2, which is different from monomer M1 and defined as in claim 1, wherein the amounts of the monomers M1 and M2 are each based on the total amount of all reactive monomers M; a2) 5 to 40% by weight based on the total amount of the resulting aqueous polymer dispersion of at least one hydrophobic organic solvent; a3) 5 to 60% by weight based on the total amount of the resulting aqueous polymer dispersion of at least one water miscible solvent; a4) 0.1 to 20% by weight based on the total amount of the resulting aqueous polymer dispersion of at least one ionic surfactant; and b) ultrasonic processing or homogenization of the aqueous monomer dispersion of step a); c) addition of at least one polymerization initiator.

15. Method according to claim 14, wherein the mixture obtained in step a) is treated for at least 5 minutes.

16. Method according to claim 14, wherein after step b) the aqueous monomer dispersion is obtained in form of a miniemulsion.

17. Aqueous polymer dispersion of claim 1, wherein the dispersion is free of protective colloids.

Description

EXAMPLES

(1) Used starting materials

(2) TABLE-US-00001 Solvesso ® 150 ND high boiling aromatic hydrocarbon mixture supplied by ExxonMobil Chemical Company, aromatic hydrocarbon > 99 vol %, initial boiling point 184° C. (ASTM D86), flash point 64° C. (ASTM D93) Behenyl acrylate isomer mixture of 40-55% by weight of C.sub.18-alkyl chain, < 15% by weight of C.sub.20-alkyl chain and 35-45-% by weight of C.sub.22-alkyl chain, Behenyl acrylate BEA 1822F of BASF SE Protective Colloid modified styrene-acrylate polymer (M.sub.w~8500 g/mol, acid number: 216, T.sub.g = 91° C.), neutralized with NH.sub.3, 31% by weight in water, Joncryl 8078 of BASF SE Non-ionic surfactant C.sub.16C.sub.18 saturated fatty alcohol ethoxylate (C.sub.16C.sub.18—O—(CH.sub.2CH.sub.2O).sub.18H, Lutensol ® AT18 as 20% aqueous solution of BASF SE Non-ionic surfactant C.sub.13C.sub.15 oxo alcohol ethoxylate (C.sub.13C.sub.15—O—(CH.sub.2CH.sub.2O).sub.5H, Lutensol ® AO5 of BASF SE Ionic surfactant .sup.nC.sub.12H.sub.25—O—(CH.sub.2CH.sub.2O).sub.4—SO.sub.3.sup.−Na.sup.+ , Disponil FES 32 of BASF SE Redox initiator Brüggolit ® FF6M (disodium salts of 2-hydroxy-2-sufinatoacetic acid system and 2-hydroxy-2-sufonatoacetic acid) from Brüggemann Chemical L-Ascorbic acid from Sigma-Aldrich Tert-butyl hydroperoxide, 10% in water (PEROXAN BHP-10) from Pergan GmbH Acid function Succinic anhydride and polyphosphoric acid were obtained from generator Merck KGaA Water soluble 1,2 Propanediol was obtained from BASF SE solvent

(3) General instructions:

(4) The particle sizes/particle diameters or particle radii indicated here for the polymer particles are particle diameters as may be determined by means of photon correlation spectroscopy (PCS), also known as quasi-elastic light scattering (QELS) or dynamic light scattering. The average particle diameters D50 constitute the average value of the cumulant analysis (mean of fits). This “mean of fits” is an average, intensity-weighted particle diameter in nm, which corresponds to the weight-average particle diameter. The measurement method is described in the ISO 13321 standard. Processes for this purpose are familiar to the skilled worker, moreover, from the relevant technical literature for example, from H. Wiese in D. Distler, Wässrige Polymerdispersionen, Wiley-VCH 1999, section 4.2.1, p. 40ff and literature cited therein, and also H. Auweter, D. Horn, J. Colloid Interf. Sci. 105 (1985) 399, D. Lilge, D. Horn, Colloid Polym. Sci. 269 (1991) 704 or H. Wiese, D. Horn, J. Chem. Phys. 94 (1991) 6429. The particle diameters indicated here relate to the values determined at 20° C. and 101.325 hPa on 0.001-1% by weight dispersions. The determination of the average particle diameters may also be performed by means of hydrodynamic chromatography (HDC) using a Particle Size Distribution Analyser (PSDA, Varian Deutschland GmbH) with a number 2 (standard) cartridge at a wavelength of 254 nm (measurement temperature 23° C. and measurement time 480 seconds). In the present invention, particle size was determined by using a NANO-flex particle sizer from Microtrac using a 780 nm laser light (3 mW) at a 180° scattering angle. Measurements were done with samples tel quel diluted to the required concentration with demineralized water at room temperature.

(5) The mini-emulsion of the solution of the monomer behenylacrylate, its comonomers in the hydrophobic solvent can be prepared from a OW-macro emulsion of the of the same by subjecting the macro-emulsion to strong shear forces, thereby achieving a comminution of the large droplets of the macro-emulsion to the desired droplet size. The means for transforming a conventional macro-emulsion to a mini-emulsion are known from prior art and can be applied to the a OW-macro emulsion of the of the solution of the monomer behenylacrylate, its comonomers in the hydrophobic solvent. Suitable means have been described e.g. in Prog. Polym. Sci. 2002, 27, 689, US 2006/0287416 and WO 2008/003601 and the literature cited therein. Comminution may be achieved by using high shear force dispersion devices like for example a ultrasonic sound equipment (J. Dispersion Sci. Technology 2002, 23(1-3), 333-349) or a high pressure homogenizer (APV Gaulin homogenizer; Microfluidizer). The emulsification and comminution can be carried out continuously or batchwise. Apparatus for this purpose are known in the art. This is for example described in U.S. Pat. No. 5,108,654.

(6) Treatment with ultrasound was carried out using a Hielscher ultrasound generator using a Sonotrode H14 with 100% power (400 W), while stirring the sample.

(7) Treatment with the Gaulin homogenizer was done with an APV 1000 lab homogenizer from SPX Flow at various pressures indicated in the experimental part.

(8) The solid content of the dispersions was determined in weight percent using a Halogen dryer model HR73 from Mettler Toledo at 150° C. and 0.5 g of sample size.

(9) GPC was measured on an Agilent 1260 Infinity apparatus against polystyrene standards in 5 mg/ml THF solutions on 2 sequential PolyPore 300 mm×7.5 mm Agilent columns at 40° C. and 1 ml/min flow. Detection of the signals was done by refractive index and the data were processed using Agilent GPC/SEC Software Version 1.2. Reported values refer to weight average molecular weights (Mw) and were rounded to the nearest hundreds digit.

(10) The following examples illustrate the invention.

(11) Comparative example C1 according to PCT/EP2017/055423

(12) For the preparation of a stable oil/water emulsion 280 g of melted behenylacrylate was dissolved in 164.4 g of Solvesso 150 ND and stirred until a homogenous and clear solution was obtained. To this solution, under stirring, 70.0 g of Lutensol AT 18 and 282.3 g of Joncryl 8078 dissolved in 112.3 g of water were slowly added. Subsequently 127.9 g of 1,2-propanediol were added to the emulsion while stirring.

(13) After stirring for 15 min and treatment with an APV homogenizer at 300 bar a stable mini-emulsion was obtained with an average droplet size below 300 nm.

(14) The emulsion was heated up to 60° C. under a nitrogen atmosphere. 56.0 g of tert-butyl hydroperoxide (10% solution in water) was added. Subsequently, 42.75 g of ascorbic acid (20% solution in water) was added over a period of 1.5 hours to the reaction mixture.

(15) The reaction mixture was continuously stirred by a mechanical stirrer and was maintained at 60° C. for one hour, then cooled to RT and filtered via a 125 mm filter. No coagulum was found. The final dispersion was obtained as a white opaque, slightly viscous liquid.

(16) The resulting particle size of the dispersion D50 was 333 nm, the solid content was 33.1% and the Mw was 45400 g/mol. The dynamic viscosity was 225 mPas (RT).

(17) Surfactant A

(18) (Synthesis of anionic phosphate surfactant from non-ionic surfactant Lutensol AO 5)

(19) In a three necked flask with thermometer, cooler and nitrogen inlet, 200 g of Lutensol AO 5 (1 equiv) was heated to 40° C. under a N.sub.2 atmosphere. Under vigorous stirring, 52.4 g of Polyphosphoric acid (pre-heated to 60° C., 0.33 equiv) was introduced slowly in a few minutes. The reaction mixture was exothermic and subsequently stirred at 90° C. for one hour. The resulting slightly yellowish and clear polymer had a solid content of 99.1% and an acid value of 252 mg KOH/g. For obtaining a water soluble surfactant, the polymer was cooled to 40° C. Then 170 g of it was transferred slowly to a stirred solution of 15 g of NaOH dissolved in 300 g of water, until a pH of 7.5 was reached, while stirring at 60° C. The clear polymer solution was foamy and had a solid content of 37.7%, and was used as such.

(20) Surfactant B

(21) (Synthesis of anionic carboxylic acid surfactant in form of succinic acid mono ester from non-ionic surfactant Lutensol AO 5)

(22) In a three necked flask with thermometer, cooler and nitrogen inlet, 200 g of Lutensol AO 5 (1 equiv) was heated to 40° C. under N.sub.2 atmosphere. Under stirring, 46.6 g of succinic anhydride flakes (1 equiv) were was introduced slowly in a few minutes. The reaction mixture was heated to 150° C. in 4 hours and stirred for two hours. The acid value was 103 mg KOH/g. After cooling to 50° C., 69.5 g of triethanolamine (1 equiv) was added dropwise in a few minutes and stirred for 1 h at 50° C. The resulting polymer salt was a liquid viscous clear material with a pH of 7.0 (as 10% aqueous solution), and was used as such.

(23) Surfactant C

(24) Disponil FES 32 is commercially available.

Example 1—Surfactant C

(25) For the preparation of a stable oil/water emulsion 280 g of melted behenylacrylate was dissolved in 164.4 g of Solvesso 150 ND and stirred until a homogenous and clear solution was obtained. While stirring, 93.3 g of Disponil FES 32 was added slowly, followed by 186.2 g of water and 127.9 g of 1,2-propanediol.

(26) After stirring for 15 min and treatment with an APV homogenizer at 300 bar and a second pass at 100 bar, a stable emulsion was obtained with an average droplet size below 200 nm.

(27) The emulsion was heated up to 60° C. under a nitrogen atmosphere. 61.1 g of tert-butyl hydroperoxide (10% solution in water) was added. Subsequently, 50.4 g of Brüggolit FF6M (20% solution in water) was added over a period of 2.5 hours to the reaction mixture.

(28) The reaction mixture was continuously stirred by a mechanical stirrer and was maintained at 60° C. for one hour, then cooled to RT and filtered via a 125 mm filter. No coagulum was found. The final dispersion was obtained as a white opaque, slightly viscous liquid.

(29) The resulting particle size of the dispersion D50 was 169 nm, the solid content was 31.5% and the Mw was 53200 g/mol. The dynamic viscosity was 100 mPas (RT).

Example 2—Surfactant A

(30) For the preparation of a stable oil/water emulsion 280 g of melted behenylacrylate was dissolved in 164.4 g of Solvesso 150 ND and stirred until a homogenous and clear solution was obtained. While stirring, 74.3 g of Surfactant A was added slowly, followed by 215.6 g of water and 127.9 g of 1,2-propanediol.

(31) After stirring for 15 min and treatment with an APV homogenizer at 300 bar and a second pass at 100 bar, a stable emulsion was obtained with an average droplet size below 200 nm.

(32) The emulsion was heated up to 60° C. under a nitrogen atmosphere. 61.1 g of tert-butyl hydroperoxide (10% solution in water) was added. Subsequently, 50.4 g of Brüggolit FF6M (20% solution in water) was added over a period of 2.5 hours to the reaction mixture.

(33) The reaction mixture was continuously stirred by a mechanical stirrer and was maintained at 60° C. for one hour, then cooled to RT and filtered via a 125 mm filter. No coagulum was found. The final dispersion was obtained as a white opaque, slightly viscous liquid.

(34) The resulting particle size of the dispersion D50 was 139 nm, the solid content was 32.4% and the Mw was 49400 g/mol. The dynamic viscosity was 129 mPas (RT).

Example 3—Surfactant B

(35) For the preparation of a stable oil/water emulsion 280 g of melted behenylacrylate was dissolved in 164.4 g of Solvesso 150 ND and stirred until a homogenous and clear solution was obtained. While stirring, 28.0 g of Surfactant B was added slowly, followed by 263.2 g of water and 127.9 g of 1,2-propanediol.

(36) After stirring for 15 min and treatment with an APV homogenizer at 300 bar and a second pass at 100 bar, a stable emulsion was obtained with an average droplet size below 200 nm.

(37) The emulsion was heated up to 60° C. under a nitrogen atmosphere. 61.1 g of tert-butyl hydroperoxide (10% solution in water) was added. Subsequently, 50.4 g of Brüggolit FF6M (20% solution in water) was added over a period of 2.5 hours to the reaction mixture.

(38) The reaction mixture was continuously stirred by a mechanical stirrer and was maintained at 60° C. for one hour, then cooled to RT and filtered via a 125 mm filter. No coagulum was found. The final dispersion was obtained as a white opaque, slightly viscous liquid.

(39) The resulting particle size of the dispersion D50 was 191 nm, the solid content was 30.7% and the Mw was 57300 g/mol. The dynamic viscosity was 94 mPas (RT).

Example 4—Copolymer with n-butylacrylate

(40) For the preparation of a stable oil/water emulsion 266 g of melted behenylacrylate and 14.0 g of n-butylacrylate were dissolved in 164.4 g of Solvesso 150 ND and stirred until a homogenous and clear solution was obtained. While stirring, 186.2 g of Disponil FES 32 was added slowly, followed by 93.3 g of water and 127.9 g of 1,2-propanediol.

(41) After stirring for 15 min and treatment with an APV homogenizer at 300 bar and a second pass at 100 bar, a stable emulsion was obtained with an average droplet size below 200 nm.

(42) The emulsion was heated up to 60° C. under a nitrogen atmosphere. 61.1 g of tert-butyl hydroperoxide (10% solution in water) was added. Subsequently, 50.4 g of Brüggolit FF6M (20% solution in water) was added over a period of 2.5 hours to the reaction mixture.

(43) The reaction mixture was continuously stirred by a mechanical stirrer and was maintained at 60° C. for one hour, then cooled to RT and filtered via a 125 mm filter. No coagulum was found. The final dispersion was obtained as a white opaque, slightly viscous liquid.

(44) The resulting particle size of the dispersion D50 was 147 nm, the solid content was 35.0% and the Mw was 51700 g/mol. The dynamic viscosity was 145 mPas (RT).

Examples 5 to 8

(45) The following examples were prepared according to procedure example 4 with the comonomers listed in below table, instead of n-butylacrylate, and was replaced by weight:

(46) TABLE-US-00002 Particle Dyn. Solid size Viscosity Mw Example Comonomer content D50 (mPas) (g/mol) 5 styrene 34.0% 151 nm 110 38100 6 2-ethylhexyl acrylate 34.0% 154 nm 124 50300 7 methyl methacrylate 33.9% 147 nm 122 51400 8 2-hydroxyethyl 34.0% 200 nm 440 50500 methacrylate

(47) All dispersions were obtained free of coagulum as white opaque slightly viscous liquids.

Example 9-15% Ionic Surfactant

(48) For the preparation of a stable oil/water emulsion 280 g of melted behenylacrylate was dissolved in 164.4 g of Solvesso 150 ND and stirred until a homogenous and clear solution was obtained. While stirring, 140 g of Disponil FES 32 was added slowly, followed by 186.2 g of water and 127.9 g of 1,2-propanediol.

(49) After stirring for 15 min and treatment with ultrasound for 2 minutes, a stable emulsion was obtained with an average droplet size below 200 nm.

(50) The emulsion was heated to 60° C. under a nitrogen atmosphere. 61.1 g of tert-butyl hydroperoxide (10% solution in water) was added. Subsequently, 50.4 g of Brüggolit FF6M (20% solution in water) was added over a period of 2.5 hours to the reaction mixture.

(51) The reaction mixture was continuously stirred by a mechanical stirrer and was maintained at 60° C. for one hour, then cooled to RT and filtered via a 125 mm filter. No coagulum was found. The final dispersion was obtained as a white opaque, slightly viscous liquid.

(52) The resulting particle size of the dispersion D50 was 167 nm, the solid content was 32.2% and the Mw was 61500 g/mol. The dynamic viscosity was 185 mPas (RT).

Example C2—with Protective Colloid

(53) For the preparation of a stable oil/water emulsion 280 g of melted behenylacrylate was dissolved in 164.4 g of Solvesso 150 ND and stirred until a homogenous and clear solution was obtained. While stirring, 225.81 g of Joncryl 8078,65,3 g of Disponil FES 32 (7 pphm, parts per hundred parts of monomer) were added slowly, followed by 252 g of water and 127.9 g of 1,2-propanediol.

(54) After stirring for 15 min and treatment with an APV homogenizer at 300 bar, a stable emulsion was obtained with an average droplet size below 200 nm.

(55) The emulsion was heated up to 60° C. under a nitrogen atmosphere. 56.0 g of tert-butyl hydroperoxide (10% solution in water) was added. Subsequently, 28.0 g of Brüggolit FF6M (20% solution in water) was added over a period of 1.5 hours to the reaction mixture.

(56) The reaction mixture was continuously stirred by a mechanical stirrer and was maintained at 60° C. for one hour, then cooled to RT and filtered via a 125 mm filter. No coagulum was found. The final dispersion was obtained as a white opaque, slightly viscous liquid.

(57) The resulting particle size of the dispersion D50 was 162 nm, the solid content was 34.3% and the Mw was 53000 g/mol.

Examples C3 and C4

(58) The following examples were prepared according to procedure C2 with variation in the amount of surfactant, while keeping the other ingredients the same, as indicated in below table.

(59) TABLE-US-00003 Solid Particle size Mw Example Surfactant content D50 (g/mol) C3 10 pphm Disponil FES 32 31.0% 193 nm 50500 (93.3 g) C4 15 pphm Disponil FES 32 32.2% 185 nm 54100 (140.0 g)

Example C5

(60) Example C5 corresponds to example 1 except that Solvesso 150 NT was omitted so that example C5 does not contain component c) (hydrophobic organic solvent).

(61) Stability of the Dispersions:

(62) The stability of the dispersions was tested at three different temperatures: −10° C., room temperature (21-23° C.) and 50° C. 20 ml of each dispersion were stored in glass bottles at the three different temperatures for several days (see Table 1). The dispersions were accurately observed. It was checked if they showed a separation or creaming/sedimentation. To quantify the stability of the dispersion the following criteria were developed:

(63) 1: Dispersion was stable and homogeneous. No creaming/sedimentation or separation could be observed. Dispersion was also fluid. No solidification or gelling.

(64) 2: Dispersion was stable with slight streaking formation. No creaming/sedimentation or separation could be observed. Dispersion was also fluid. No solidification or gelling

(65) 3: Dispersion showed a separation. Creaming or sedimentation might be observed. Some dispersions did not flow anymore.

(66) In addition to the visual check, the solid content of the dispersions was measured. For this, 1.0 g from the top and 1.0 g from the bottom of the sample were taken and the solid content of each aliquot was determinated. (Measurement conditions: 1.0 g sample, temperature 120° C., fully automatic end point recognition: no weight difference for 24 seconds). For the solid content measurement, a Sartorius moisture analyzer type MA 150 was used. A difference of 5 absolute %-values between the solid content of the top aliquot and that of the bottom aliquot indicated that the dispersion was unstable

(67) TABLE-US-00004 Solid content.sup.B/ Solid content.sup.B/ Storage/ Stability.sup.A % at RT Stability.sup.A % at −10° C. Example days RT top bottom −10° C. top bottom C1 9 1 34.9 34.7 2 35.3 36.6 1 21 1 38.1 34.9 1 33.7 35.2 2 9 1 33.6 33.8 1 33.6 33.5 3 9 1 34.4 33.9 1 34.1 34.1 Solid content.sup.B/ Storage/ Stability.sup.A % at 50° C..sup.C Example days 50° C. top bottom C1 9 3 47.9 25.0 1 21 1 36.3 35.2 2 9 1 33.2 33.4 3 9 1 33.6 33.0

(68) A: stability of dispersion:

(69) 1: Dispersion was stable and homogeneous. No creaming/sedimentation or separation could be observed. Dispersion was also fluid. No solidification or gelling.

(70) 2: Dispersion was stable with slight streaking formation. No creaming/sedimentation or separation could be observed. Dispersion was also fluid. No solidification or gelling

(71) 3: Dispersion showed a separation. Creaming or sedimentation might be observed. Some dispersions did not flow anymore.

(72) B: Solid content (dry weight) in %.

(73) TABLE-US-00005 Solid content.sup.B/ Solid content.sup.B/ Storage/ Stability.sup.A % at RT Stability.sup.A - % at −10° C. Example days RT top bottom −10° C. top bottom C1 9 1 34.9 34.7 2 35.3 36.6 1 21 1 38.1 34.9 1 33.7 35.2 4 21 1 35.4 35.4 1 36.2 36.3 5 21 1 34.1 34.2 1 34.4 34.8 6 21 1 33.7 35.8 1 35.2 35.1 7 21 1 34.9 34.8 1 35.4 35.1 8 21 1 34.1 35.4 2 36.6 35.8 Solid content.sup.B/ Storage/ Stability.sup.A % at 50° C. Example days 50° C. top bottom C1 9 3 47.9 25.0 1 21 1 36.3 35.2 4 21 2 35.1 34.8 5 21 2 34.5 32.9 6 21 1 34.7 35.3 7 21 1 34.7 33.7 8 21 2 34.5 34.0

(74) A: stability of dispersion:

(75) 1: Dispersion was stable and homogeneous. No creaming/sedimentation or separation could be observed. Dispersion was also fluid. No solidification or gelling.

(76) 2: Dispersion was stable with slight streaking formation. No creaming/sedimentation or separation could be observed. Dispersion was also fluid. No solidification or gelling

(77) 3: Dispersion showed a separation. Creaming or sedimentation might be observed. Some dispersions did not flow anymore.

(78) B: Solid content (dry weight) in %.

(79) Pour Point Determination of Crude Oil Treated with Dispersions

(80) The pour point (PP) and no flow point (NFP) was determined with a Pour Point-Tester 45150 from PSL (Osterode am Harz, Germany). The pour point is measured according to ASTM D5985. As crude oil, a Wintershall oil from the Landau region, Germany, was used. The crude oil has a API of 37°.

(81) A 2 liter aluminum bottle containing the crude oil was heated to 80° C. for 30 minutes. During the heating process the bottle was shaken repeatedly to homogenize the crude oil. Then 50 ml of the crude oil were transferred to a 100 ml plastic bottle. The bottle was heated to 80° C. again for 15 minutes. After that 1000 ppm of the dispersion were added to the crude oil. Then the crude oil with the dispersion was shaken. Finally, the sample was heated to 80° C. again for 15 min. Approximately 30 ml of the sample were then transferred to the cup of the pour point tester so that it was filled up to the calibration line. The cup was inserted into the pour point tester, the sensor head was put into the sample and the measuring was started. The sample was firstly heated until 70° C. before the pour point measurement was started.

(82) Performance of samples stored at room temperature

(83) TABLE-US-00006 PP/° C. NFP/° C. Sample 1000 ppm 1000 ppm blank 21 18.5 C1 12 11.5 1 9 6.0 2 9 6.1 3 6 5.8 4 9 7.3 5 12 9.7 6 9 8.5 7 9 6.4 8 9 7.1 C5 28 17.6

(84) Performance of samples stored at 50° C.

(85) TABLE-US-00007 PP/° C. NFP/° C. Sample 1000 ppm 1000 ppm Blank 21 18.5 C1 12 10.8 1 6 5.6 2 9 6.6 3 9 7.7 4 9 7.2 5 12 9.7 6 9 8.8 7 9 6.9 8 9 7.5 C5 21 18.0

(86) TABLE-US-00008 Solid content.sup.B/ Solid content.sup.B/ Storage/ Stability.sup.A % at RT Stability.sup.A % at −10° C Example days RT top bottom −10° C. top bottom 1 21 1 38.1 34.9 1 33.7 35.2 C2 10 3 35.8 25.1 1 32.9 32.2 C3 10 3 35.2 20.4 3 33.9 27.4 C4 10 3 36.1 23.2  3.sup.C 33.5 32.4 C5 28 3 67.0 33.7 3 53.4 34.0 Solid content.sup.B/ Storage/ Stability.sup.A %.sup.C at 50° C. Example days 50° C. top bottom 1 21 1 36.3 35.2 C2 10 3 50.5 19.4 C3 10 3 39.7 19.8 C4 10 3 43.3 20.5 C5 28 3 63.9 25.5

(87) A: stability of dispersion:

(88) 1: Dispersion was stable and homogeneous. No creaming/sedimentation or separation could be observed. Dispersion was also fluid. No solidification or gelling.

(89) 2: Dispersion was stable with slight streaking formation. No creaming/sedimentation or separation could be observed. Dispersion was also fluid. No solidification or gelling

(90) 3: Dispersion showed a separation. Creaming or sedimentation might be observed. Some dispersions did not flow anymore.

(91) B: Solid content (dry weight) in %.

(92) C: dispersion is solid.

(93) Wax Inhibition—Cold Finger Test

(94) The cold finger deposition test was utilized to determine the wax inhibition properties of the dispersions. The wax inhibition was determined by exposing the crude oil to a cold metal finger surface in the presence and absence of the inhibitor. The amount and type of wax deposited on the cold metal finger was used to determine waxing tendency. For the tests, a crude oil from the “Landau” oilfield in south-west Germany (Wintershall Holding GmbH) having an API gravity of 37 and a pour point of 21° C. was used. The test was started by conditioning the oil sample by heating to 80° C. and holding for 30 minutes to remove thermal history. A water bath on the cold finger apparatus was adjusted so that the oil temperature was maintained at 30° C. The cold finger was maintained at 15° C. and the cold finger was inserted into the oil sample. The test was run for 6 hours. The cold finger was removed, and the wax deposit on it was collected with a paper towel. The wax deposit was weighed. The wax test was repeated in the presence and absence of the inventive dispersion. The amount of dispersion used was 1000 ppm with respect to crude oil. The percent efficacy was calculated on the performance of paraffin inhibitor as compared to the baseline (i.e. the measurement without wax inhibitor. The results are summarized in the following table:

(95) TABLE-US-00009 Cold finger test Wax Example wax deposition/g inhibition/% Blank 2.84 — 1 1.76 38