2-DIMETHYLAMINOETHYL ACRYLATE POLYMERS AND THEIR PREPARATION METHOD

Abstract

The present invention relates to a water-soluble polymer obtained by polymerization of at least a 2-dimethylaminoethyl acrylate monomer and/or its salts, in presence of at least a tocopherol and/or its derivatives, or a tocotrienol and/or its derivatives, and its uses.

Claims

1. A water-soluble polymer obtained by polymerization of at least a 2-dimethylaminoethyl acrylate monomer and/or its salts, in presence of at least a tocopherol and/or its derivatives, or a tocotrienol and/or its derivatives.

2. A water-soluble polymer according to claim 1, said water-soluble polymer being obtained by polymerization of at least a 2-dimethylaminoethyl acrylate monomer and/or its salts in presence of at least an α-tocopherol.

3. A water-soluble polymer according to claim 1, wherein the quantity of tocopherol and/or its derivatives, or tocotrienol and/or its derivatives is comprised between 1 ppm and 10 000 ppm, based on the amount of 2-dimethylaminoethyl acrylate monomer and/or its salts.

4. A water-soluble polymer according to claim 1, wherein the tocopherol and/or its derivatives, or the tocotrienol and/or its derivatives, is added to the 2-dimethylaminoethyl acrylate monomer and/or its salts after the synthesis of said 2-dimethylaminoethyl acrylate monomer and/or its salts.

5. A water-soluble polymer according to claim 1, wherein the tocopherol and/or its derivatives, or the tocotrienol and/or its derivatives is added to the 2-dimethylaminoethyl acrylate monomer and/or its salts before the storage of said 2-dimethylaminoethyl acrylate monomers and/or its salts.

6. A water-soluble polymer according to claim 1, wherein the 2-dimethylaminoethyl acrylate monomer is quaternized with methyl chloride.

7. A water-soluble polymer according to claim 1, wherein the water-soluble polymer comprises at least 1 mol % of 2-dimethylaminoethyl acrylate monomer and/or its salts based on the total number of moles of monomers.

8. A water-soluble polymer according to claim 1, wherein the water-soluble polymer has an average molecular weight by weight comprised between 50 000 g/mol and 30 000 000 g/mol.

9. A composition comprising: from 1 to 99.9999 w % of at least one 2-dimethylaminoethyl acrylate monomer and/or its salts; from 1 to 10 000 ppm of at least a tocopherol and/or its derivatives, or a tocotrienol and/or its derivatives, based on the amount of 2-dimethylaminoethyl acrylate monomer and/or its salts, Optionally at least an additive chosen from biocides, polymerization inhibitors, humidity absorbers, colour stabilisers.

10. A composition according to claim 9, comprising at least one colour stabiliser chosen from: niacinamide, retinol, 3-tertiobutyl-4-hydroxyanisole (3-BHA), 2-tertiobutyl-4-hydroxyanisole and 2,6,-di-tert-butyl-4-methylphenol.

11. A composition according to claim 9, wherein the ratio in weight between the tocopherol and/or its derivatives or the tocotrienol and/or its derivatives and the colour stabiliser is comprised between 1 and 100.

12. Use of the water-soluble polymer of claim 1 in water treatment, sludge dewatering, papermaking process, agriculture, cosmetic and detergency composition, textile process, oil and gas process.

13. Use of the water-soluble polymer of claim 1 as a dispersant, coagulant, flocculant, thickener, grinding agent, drag reducer, superabsorbent, retention aid.

14. Process for inhibiting the formation of vinyl acrylate resulting from a reaction between at least a 2-dimethylaminoethyl acrylate monomer and/or its salts and oxygen, comprising mixing said 2-dimethylaminoethyl acrylate monomer and/or its salts with a tocopherol and/or its derivatives, or a tocotrienol and/or its derivatives.

15. A water-soluble polymer according to claim 2, wherein the quantity of tocopherol and/or its derivatives, or tocotrienol and/or its derivatives is comprised between 1 ppm and 10 000 ppm, based on the amount of 2-dimethylaminoethyl acrylate monomer and/or its salts.

16. A water-soluble polymer according to claim 15, wherein the tocopherol and/or its derivatives, or the tocotrienol and/or its derivatives, is added to the 2-dimethylaminoethyl acrylate monomer and/or its salts after the synthesis of said 2-dimethylaminoethyl acrylate monomer and/or its salts.

17. A water-soluble polymer according to claim 16, wherein the tocopherol and/or its derivatives, or the tocotrienol and/or its derivatives is added to the 2-dimethylaminoethyl acrylate monomer and/or its salts before the storage of said 2-dimethylaminoethyl acrylate monomers and/or its salts.

18. A water-soluble polymer according to claim 17, wherein the 2-dimethylaminoethyl acrylate monomer is quaternized with methyl chloride.

19. A water-soluble polymer according to claim 18, wherein the water-soluble polymer: comprises at least 1 mol % of 2-dimethylaminoethyl acrylate monomer and/or its salts based on the total number of moles of monomer; and has an average molecular weight by weight comprised between 50 000 g/mol and 30 000 000 g/mol.

20. A composition according to claim 10, wherein the ratio in weight between the tocopherol and/or its derivatives or the tocotrienol and/or its derivatives and the colour stabiliser is comprised between 1 and 100.

Description

FIGURE DESCRIPTION

[0296] FIG. 1 illustrates the evaluation of the friction reduction effect of polymer 1 to 5 by FlowLoop tests.

EXAMPLES

Example 1—Storage & Insolubility Rate

[0297] Preparation of the Composition

[0298] At the end of the 2-dimethylaminoethyl acrylate (DMAEA) monomers synthesis, the monomers are purified via distillation. The distillate fraction, at minimum 9800, of 2-dimethylaminoethyl acrylate monomers is collected. A polymerization inhibitor, monomethyl ether hydroquinone, is added (1000 ppm) and homogeneously mixed. The tocopherol and/or its derivatives, or a tocotrienol and/or its derivatives is then added and homogenously mixed for 30 minutes at 20° C. under air atmosphere. The prepared composition is then transferred to storage and store under air atmosphere for 1 to 12 months. The 2-dimethylaminoethyl acrylate monomers are classically quaternized with methyl chloride, the quaternization being per see known by the skilled person, before being polymerized.

[0299] The different compositions prepared are summarized up in table 3.

TABLE-US-00003 TABLE 3 Tocopherols Tocopherols or or tocotrienols Composition tocotrienols concentration Composition 1 — — reference Composition 2 α-tocopherol  20 ppm invention Composition 3 200 ppm invention Composition 4 γ-tocopherol  25 ppm invention Composition 5 250 ppm invention Composition 6 α-tocotrienol  20 ppm invention Composition 7 300 ppm invention Composition 8 α-tocopherol +  20 ppm invention 30 ppm of 2,6,- Composition 9 di-tert-butyl-4- 200 ppm invention methylphenol

[0300] The vinyl acrylate concentration in the 2-dimethylaminoethyl acrylate monomers is determined using GC analysis; instrument Agilent 7820A with a MS detector equipped with DB-WAX column 30 m, helium for gas carrier at 1 mL/min. Injector temperature and transfer line are maintained at 250° C. Injection is done with 1 μL at 1:100 split ratio. The oven temperature is at 80° C. for 5 min, then increased at 5° C./min to 122° C. for 2 min, then temperature is increased to 240° C. at 35° C./min for 11 min.

[0301] Storage & Insolubility Rate in Polymer Preparation

[0302] The UL viscosity (Brookfield viscosity), the insolubility rate and the insolubility point are measured on a 70 mol % of acrylamide and 30 mol % of quaternized DMAEA polymer prepared by classical bulk polymerization.

[0303] Measurement of UL viscosity: the UL viscosity is measured using a Brookfield viscometer equipped with a UL adapter, the unit of which rotates at 60 revolutions/minute (0.1 percent by weight of polymer in a 1M saline sodium chloride solution) between 23 and 25° C.

[0304] The insolubility rate is measured by transferring 1 g of the polymer solution in 200 ml of water at 20° C., stirring for 2h, then the dissolved solution is filtered with a 4 cm diameter filter with a porosity of 200 μm. After the filtered solution is completely drained, the filter paper is weighted. In case of a non filtrable solution the screen filter is placed at 105° C. for 4 hours. The residual mass is used to determine the insoluble quantity, insolubility rate is related to the initial polymer mass. As mentioned above, the vinyl acrylate impurity creates covalent bonds between 2-dimethylaminoethyl acrylate monomers resulting in aggregates which do not pass into the filter.

[0305] The insolubility point corresponds to the number and size of aggregates on the filter, after the whole solution is passed through the filter, visually counted. The following scale is used: point (pt) between 1 and 3 mm; big point (bp) for more than 3 mm.

TABLE-US-00004 TABLE 4 Vinyl acrylate concentration in 2- UL dimethylaminoethyl viscosity Insolubility Insolubility Composition Duration acrylate monomers (cps) points rate Composition 1  1 month 10 ppm 5.3 10 pts 1% reference  3 months 15 ppm 5.3 20 bps 2%  6 months 40 ppm Not Not 100%  measurable filtrable 12 months 60 ppm Not Not 100%  measurable filtrable Composition 2  1 month  2 ppm 5.3 5 pts 1% Invention  3 months  5 ppm 5.3 10 pts 1%  6 months 10 ppm 5.3 30 pts 2% 12 months 19 ppm 5.0 10 bps 1% Composition 3  1 month  1 ppm 5.2 5 pts 1% Invention  3 months  5 ppm 5.3 10 pts 1%  6 months  8 ppm 5.1 30 pts 2% 12 months 18 ppm 5.3 10 bps 2% Composition 4  1 month  3 ppm 5.3 6 pts 1% invention  3 months  7 ppm 5.3 10 pts 1%  6 months 10 ppm 5.0 30 pts 2% 12 months 20 ppm 5.2 20 bps 2% Composition 5  1 month  2 ppm 5.3 10 pts 1% invention  3 months  4 ppm 5.3 10 pts 1%  6 months 12 ppm 5.3 30 pts 2% 12 months 19 ppm 5.0 10 bps 2% Composition 6  1 month  3 ppm 5.2 10 pts 1% invention  3 months  5 ppm 5.3 10 pts 1%  6 months 10 ppm 5.1 30 pts 2% 12 months 19 ppm 5.3 10 bps 2% Composition 7  1 month  1 ppm 5.3 10 pts 1% invention  3 months  4 ppm 5.3 10 pts 1%  6 months  7 ppm 5.0 30 pts 2% 12 months 18 ppm 5.2 15 bps 2% Composition 8  1 month  1 ppm 5.3 10 pts 1% invention  3 months  3 ppm 5.1 10 pts 1%  6 months  8 ppm 5.0 30 pts 2% 12 months 15 ppm 5.2 8 bps 2% Composition 9  1 month <1 ppm 5.1 2 pts <1%   invention  3 months  2 ppm 5.2 5 pts 1%  6 months  5 ppm 5.3 20 pts 1% 12 months 12 ppm 5.3 5 bps 2%

[0306] As we can see based on table 4, the combination of the 2-dimethylaminoethyl acrylate monomers and tocopherol and/or its derivatives, or a tocotrienol and/or its derivatives reduces the formation of vinyl acrylate during the storage.

[0307] Even after only 1 month, the monomers of the invention have a reduced amount of vinyl acrylate. Thanks to the invention, monomers can be stored up to 12 months and still have an amount of vinyl acrylate equivalent to about 3 months storage of classical monomers.

[0308] Regarding the insolubility point without the combination of the invention, the number of points corresponding to polymer aggregates is more important for monomers stored without tocopherol and/or its derivatives, or a tocotrienol and/or its derivatives, even after one month.

Example 2—Friction Reduction Test

[0309] Preparation of the 2-Dimethylaminoethyl Acrylate Polymers.

[0310] Different quaternized 2-dimethylaminoethyl acrylate/acrylamide (30%/70%) copolymers were synthetised with a different weight % of 2-dimethylaminoethyl acrylate monomers coming from composition 3, prepared in example 1, after 6 months of storage. The polymers are obtained by classical bulk polymerization.

[0311] The compositions of the polymers are summarized in table 5.

TABLE-US-00005 TABLE 5 % wt DMAEA combined with α-tocopherol in Polymer the quaternized DMAEA/acrylamide copolymer Polymer 1  0 w % of 2-dimethylaminoethyl acrylate counter- example Polymer 2  5 w % of 2-dimethylaminoethyl acrylate invention Polymer 3 30 w % of 2-dimethylaminoethyl acrylate invention Polymer 4 50 w % of 2-dimethylaminoethyl acrylate invention Polymer 5 80 w % of 2-dimethylaminoethyl acrylate invention

[0312] Hydraulic Fracturing Fluid Preparation

[0313] Polymers 1 to 5 are added under stirring, at a concentration of 10,000 ppm, in a brine consisting of water, 85 g of sodium chloride (NaCl) and 33.1 g of calcium chloride (CaCl.sub.2), 2H2O) per litre of brine.

[0314] The resulting saline polymer solutions are then injected at a concentration of 0.05 pptg (pounds per thousand gallons) (which gives 0.006 g/L=6 g/m3, since 1 pptg=0.1198 g/L) into the recirculating brine for the Flow Loop tests that follow.

[0315] Flow Loop Friction Reduction Tests

[0316] A friction flow loop was constructed from ¼ inch (which gives 0.635 cm, since 1 inch=2.54 cm) outer diameter stainless steel tubing, 20 feet (which gives 6.096 m, since 1 foot=0.3048 m) in overall length. Test solutions are pumped out of the bottom of a tapered 5-liter reservoir.

[0317] The solution flows through the tubing and is returned back into the reservoir. The flow is achieved using a triplex pump equipped with a variable speed drive. 4 liters of fresh water or brine (for instance synthetic brine or sea water) is prepared in the sample reservoir and the pump is started and set to deliver a flow rate of 1.5 gal/min (1 US gal=3.78541 liters). The salt solution is recirculated until the temperature equilibrates at 25° C. and a stabilized pressure differential is achieved. This pressure is recorded as the initial pressure of the fresh water or sea water or brine. To evaluate the friction reduction of each of the polymers 1 to 5, the tank of the Flow Loop was filled with brine described above. The brine is then recirculated in the Flow Loop at a flow rate of 1.5 gal.Math.min.sup.−1. The polymer is added at a concentration of 0.05 pptg to the recirculating brine.

[0318] The test amount of polymer solution is quickly injected with a syringe into the sample reservoir containing the fresh water or sea water or brine and a timer is started. The pressure is recorded every second for 5 minutes. The percentage friction reduction (% FRt) at a given time ‘t’ is calculated from the initial pressure drop ΔPi and the pressure drop at time t, ΔPt, using the equation:

[00001]$\%{\mathrm{FR}}_t=\frac{\Delta P_i-\Delta P_t}{\Delta P_i}\times 100$

[0319] FlowLoop results are shown in FIG. 1.

[0320] Polymers prepared from the composition of the invention offer better performances, the friction reduction effect is quicker, and the maximum % FRt is higher, making these polymers more efficient than those of the state of the art.

[0321] It can be seen from FIG. 1 that the more 2-dimethylaminoethyl acrylate monomers come from the invention, the better the performances of the polymer.

Example 3—Retention Aid in Paper

[0322] Retention aid are polymers added to cellulosic fiber slurries before the formation of paper in order to improve the efficiency with which the fine particles, including cellulosic fines, are retained in the paper product.

[0323] Type of Pulp Used

[0324] Virgin Fiber Pulp:

[0325] Wet pulp is obtained by disintegrating dry pulp to obtain a final aqueous concentration of 1% by weight. It is a pH neutral pulp consisting of 90% bleached virgin long fibers, 10% bleached virgin short fibers and 30% additional GCC (ground calcium carbonate) (Hydrocal® 55 from Omya) by weight based on the weight of the fibers.

[0326] Evaluation of Total Retention and Ash Retention

[0327] For all subsequent tests, the polymer solutions are prepared at 0.5% by weight. After 45 minutes of preparation, the polymer solutions are diluted 10 times prior to injection.

[0328] The different results are obtained by using a Britt Jar type device with a stirring speed of 1000 rpm.

[0329] The sequence of the process is as follows: [0330] T=0 s: Agitation of 500 mL paper pulp at a concentration of 0.5% by weight. [0331] T=10 s: Addition of the retention agent (300 g of dry polymer/tonne of dry pulp). [0332] T=20 s: Removal of the first 20 mL corresponding to the dead volume under the wire, then recovery of 100 mL of white water.

[0333] The percentage of First Pass Retention (% FPR), corresponding to the total retention, is calculated according to the following formula: % FPR=(C.sub.HB−C.sub.WW)/C.sub.HB*100

[0334] The First Pass Ash Retention as a percentage (% FPAR) is calculated using the following formula: % FPAR=(A.sub.HB−A.sub.WW)/A.sub.HB*100 with: [0335] C.sub.HB: Headbox consistency [0336] C.sub.WW: White Water Consistency [0337] A.sub.HB: Headbox ash consistency [0338] A.sub.WW: White Water Ash Consistency

[0339] For each of these analyses, the highest values correspond to the best performances.

[0340] The same polymers as in example 2 were tested and results are summarized in table 6.

[0341] Evaluation of the Performance of Gravity Drainage Using the Canadian Standard Freeness (CSF)

[0342] In a beaker, the pulp is treated at a stirring speed of 1000 rpm.

[0343] The sequence of the process is as follows: [0344] T=0 s: Agitation of 500 mL of paper pulp at a concentration of 0.6% by weight [0345] T=10 s: Addition of the retention agent (300 g of dry polymer/tonne of dry pulp). [0346] T=20 s: Stop stirring and add the necessary amount of water to obtain 1 liter.

[0347] This liter of pulp is transferred to the Canadian Standard Freeness Tester and the TAPPI T227om-99 procedure is applied.

[0348] The volume, expressed in mL, recovered by the side tubing gives a gravity dewatering measurement. The higher the value, the better the gravity drainage.

[0349] This performance can also be expressed by calculating the percentage improvement over the blank (% CSF).

[0350] The highest values correspond to the best performances.

[0351] The same polymers as in example 2 were tested and results are summarized in table 6.

TABLE-US-00006 TABLE 6 Polymer % FPAR % FPR % CSF 1 reference 22.3 65.4 — 2 invention 25.2 66.6 5.2 3 invention 27.5 67.9 10.9 4 invention 29.1 70.2 15.1 5 invention 34.6 79.7 25.9

[0352] The polymers of the invention offer better performances as retention aid for paper.

[0353] Regarding the CSF, polymer prepared with only 2-dimethylaminoethyl acrylate monomers according to the invention offer more than 25% of improved performances.

[0354] The more 2-dimethylaminoethyl acrylate monomers come from the invention, the better the performances of the polymer.