Patent Application
20080045420
A copolymer comprising 70% by number of units deriving from SPE and 30% by number of units deriving from Bisomer S10W, with a number-average molar mass Mn=15 000 g/mol and a weight-average molar mass Mw=26 000 g/mol (relative value measured by aqueous GPC with standardizing of the samples of poly(ethylene oxide)), is prepared by radical polymerization in a water/ethanol mixture in the following way: 5.60 g of SPE (i.e., 0.020 mol) sold by Raschig, 9.45 g of Bisomer S10W (i.e., 0.009 mol) sold by Laporte, 398 g of water and 261.90 g of ethanol are charged, at ambient temperature, to a jacketed 1.5 1 multi-necked SVL reactor equipped with a Teflon anchor stirrer and connected to a thermostat. This mixture is subsequently heated to 78° C. When this temperature is reached (time recorded as t0), the following are introduced:
Once the final introduction is complete (at t0+2 h 30 min), the reaction medium is maintained at 70° C. for 1 h 30. Heating is then halted.
When the reactor has returned to ambient temperature, water is added and then the ethanol is evaporated on a rotary evaporator. The final product is an aqueous solution characterized by a solids content of 27.3% (calculated by weighing a known amount of solution before drying and after drying at 115° C. for 2 h), a pH of 2.0 and a Brookfield viscosity of 36 mPa·s (measured with an RV1 spindle, at 50 rpm, at ambient temperature).
The absolute average molar masses are also measured: Mw=65 000 g/mol, Mn=8000 g/mol.
A copolymer comprising 85% by number of units deriving from SPE and 15% by number of units deriving from Bisomer S10W, with a number-average molar mass Mn=15 000 g/mol and a weight-average molar mass Mw=23 000 g/mol (relative value measured by aqueous GPC with standardizing of the samples of poly(ethylene oxide)), is prepared by radical polymerization in a water/ethanol mixture in the following way: 8.90 g of SPE (i.e., 0.032 mol) sold by Raschig, 6.09 g of Bisomer S10W (i.e., 0.006 mol) sold by Laporte, 403.75 g of water and 261.90 g of ethanol are charged, at ambient temperature, to a jacketed 1.5 1 multi-necked SVL reactor equipped with a Teflon anchor stirrer and connected to a thermostat. This mixture is subsequently heated to 78° C. When this temperature is reached (time recorded as t0), the following are introduced:
Once the final introduction is complete (at t0+2 h 30 min), the reaction medium is maintained at 78° C. for 1 h 30. Heating is then halted.
When the reactor has returned to ambient temperature, water is added and then the ethanol is evaporated on a rotary evaporator. The final product is an aqueous solution characterized by a solids content of 21.9% (calculated by weighing a known amount of solution before drying and after drying at 115° C. for 2 h), a pH of 2.0 and a Brookfield viscosity of 31 mPa·s (measured with an RV1 spindle, at 50 rpm, at ambient temperature).
The absolute average molar masses are also measured: Mw=57 500 g/mol, Mn=6500 g/mol.
A copolymer comprising 92.5% by number of units deriving from SPE and 7.5% by number of units deriving from Bisomer S10W, with a number-average molar mass Mn=14 000 g/mol and a weight-average molar mass Mw=21 000 g/mol (relative value), is prepared in the same way, at a solids content of 25.3% by weight, in a 70/30 water/ethanol mixture. The absolute average molar masses are also measured: Mw=54 000 g/mol, Mn=7500 g/mol.
A polymer comprising essentially units deriving from SPE, with a weight-average molar mass Mw=11 300 g/mol (relative value), is prepared, at a solids content of 30% by weight, by radical polymerization in water in the following way:
90 g of SPE and 403.75 g of water are charged, at ambient temperature, to a 500 ml three-necked reactor equipped with a Teflon anchor stirrer and immersed in a thermostatically controlled oil bath. The reaction medium is subsequently heated to 98° C. When this temperature is reached (time recorded as t0), the following are introduced:
Once the final introduction is complete (at t0+15 min.), the reaction medium is maintained at 78° C. for 5 h 45 min (up to t0+6 h). Heating is subsequently halted.
The final product is an aqueous solution characterized by a solids content of 30% (calculated by weighing a known amount of solution before drying and after drying at 115° C. for 2 h), a pH of 1.5 and a Brookfield viscosity of 30 mPa·s (measured with an RV1 spindle, at 50 rpm, at ambient temperature).
The absolute molar masses are also measured: Mw=30 000 g/mol, Mn=4000 g/mol.
A copolymer comprising 99.9% by number of units deriving from SPE and 0.1% by number of GMMA units, with a number-average molar mass Mn=22 000 g/mol and with a weight-average molar mass Mw=216 000 g/mol (relative value), is prepared by radical polymerization in a water/ethanol mixture in the following way: 289.82 g of SPE (i.e., 1.073 mol) sold by Raschig, 0.18 g of GMMA (i.e., 0.001 mol) sold by Rohm and 430 g of water are charged, at ambient temperature, to a jacketed 1.5 1 multi-necked SVL reactor equipped with a Teflon anchor stirrer and connected to a thermostat. This mixture is subsequently heated to 80° C. When this temperature is reached (time recorded as t0), the following is introduced all at once (at t0): 0.2206 g of ammonium persulfate (i.e., 0.001 mol) dissolved in 20 g of water.
The reaction medium is maintained at 80° C. for 6 h. Heating is then halted.
The final product is an aqueous solution characterized by a solids content of 41.7% (calculated by weighing a known amount of solution before drying and after drying at 115° C. for 2 h). This solution is too viscous for its pH and its Brookfield viscosity to be able to be measured under the same conditions as for the polymers described in the above examples.
The absolute mean molar masses are also measured: Mw=2 000 000 g/mol, Mn=900 000 g/mol.
A copolymer comprising 95% by number of units deriving from SPE and 5% by number of GMMA units, with a number-average molar mass Mn=44 000 g/mol and with a weight-average molar mass Mw=230 000 g/mol (relative value), is prepared by radical polymerization in a water/ethanol mixture in the following way: 291.21 g of SPE (i.e., 1.073 mol) sold by Raschig, 8.79 g of GMMA (i.e., 0.055 mol) sold by Rohm and 430 g of water are charged, at ambient temperature, to a jacketed 1.5 1 multi-necked SVL reactor equipped with a Teflon anchor stirrer and connected to a thermostat. This mixture is subsequently heated to 80° C. When this temperature is reached (time recorded as t0), the following is introduced all at once (at t0): 0.2253 g of ammonium persulfate (i.e., 0.001 mol) dissolved in 20 g of water.
The reaction medium is maintained at 80° C. for 6 h. Heating is then halted.
The final product is an aqueous solution characterized by a solids content of 42.8% (calculated by weighing a known amount of solution before drying and after drying at 115° C. for 2 h). This solution is too viscous for its pH and its Brookfield viscosity to be able to be measured under the same conditions as for the polymers described in the above examples.
The absolute mean molar masses are also measured: Mw=3 400 000 g/mol, Mn=1 600 000 g/mol.
The monomer (SHPP) is synthesized and then polymerized, the final polymer being characterized by a weight-average molar mass of 200 000 g/mol (relative value).
57.16 g of CHPSNa (sodium chlorohydroxypropylsulfonate, sold by Raschig), i.e. 0.291 mol, and 943.92 g of water are charged, at ambient temperature, to a jacketed 1.5 1 multi-necked SVL reactor equipped with a Teflon anchor stirrer and connected to a thermostat. The CHPSNa dissolves in a few minutes with stirring ˜5 min). The pH of this solution is subsequently adjusted to 7.5 using dilute 10% sodium hydroxide solution. 47.72 g of dimethylaminopropylmethacrylamide, sold by Rohm, i.e. 0.280 mol, are then introduced. The mixture is heated to 80° C. and maintained at this temperature for 4 h.
The aqueous solution thus obtained (solution I) is characterized by a solids content of 24.7% (calculated by weighing a known amount of solution before drying and after drying at 115° C. for 2 h) and a pH of 8.7. The 1H NMR analysis in D2O shows that the tertiary amine monomer has been virtually completely converted to sulfobetaine monomer: 93% of the dimethylaminopropyl-methacrylamide is converted to SHPP monomer. 36.67 g of this solution I and 137.5 g of water are charged, at ambient temperature, to a jacketed 1.5 1 multi-necked SVL reactor equipped with a Teflon anchor stirrer and connected to a thermostat. The mixture is heated to 85° C. When this temperature is reached (time recorded at t0), the following are introduced:
Once the final introduction is complete (at t0+4h) the reaction medium is maintained at 85° C. for 4 h (from t0+4 h to t0+8 h). Heating is subsequently halted.
The final product is an aqueous solution characterized by a solids content of 18% (calculated by weighing a known amount of solution before drying and after drying at 115° C. for 2 h) and a pH of 6.3.
The absolute molar masses are also measured: Mw=880 000 g/mol, Mn=300 000 g/mol.
An aqueous drilling mud formulation A is prepared which comprises the following ingredients:
A silicate-based drilling mud formulation B is prepared which comprises the following ingredients:
Clay particles are used to simulate the cuttings. The clay used is Oxford clay, 2-4 mm, sold by Hanson Brick, a highly reactive and dispersive clay. The particles are sieved for a final size distribution between 2-4 mm.
30 g of sieved particles are added to 350 ml of the test formulation. The flasks are placed in a rolling oven at 65° C. for 16 hours (hot rolling). After rolling, the samples are cooled and the particles are recovered on a sieve (2 mm) and washed with a brine solution. The excess formulation is carefully removed using adsorbent paper. The particles are weighed. The particles are dried in an oven at 50° C. until a stable weight is achieved, in order to have a precise indication of the water content inside the particles. The particles are again weighed and the percentage of moisture restoration is calculated. High levels of restoration and low moisture contents indicate an inhibiting effect on clay swelling.
Hot rolling is carried out in the presence of the clay particles, at 65° C. for 16 hours, as indicated above. Afterwards, the particles are recovered on a sieve, washed with brine and extruded in a CT 15 compressometer device from Adamel Lhomargy at a rate of 40 mm/min. The pressure necessary to extrude the particles is measured. It depends on the degree of hydration of the particles. The harder the particles, the higher the pressure, the better the protection with regard to penetration of water and thus the better the inhibiting effect on clay swelling.
Eight different additives are tested at different concentrations in the fluid in accordance with the example (concentration by weight on a dry basis). The results are given in table I.
175 ml of the formulation/mud and 15 g of the clay particles are placed in 250 ml polypropylene flasks. A preweighed steel bar is added thereto and the flasks are placed horizontally on moving rollers at ambient temperature for 1 minute. The bar is subsequently removed from the flask and photographed. It is subsequently placed in an oven at 105° C. to constant weight.
The following is calculated: % accretion=weight (g) of dry particles stuck to the bar/weight (g) of particles used for the test*. *The moisture content is taken into account in order to calculate the starting weight of the clays.
The lower the value, the better it is.
The results are presented in table II below.
| Number | Date | Country | Kind |
|---|---|---|---|
| 0314675 | Dec 2003 | FR | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/FR04/03239 | 12/15/2004 | WO | 00 | 4/2/2007 |
