Low-temperature coagulation-accelerating anion styrene-butadiene latex for oil field well cementation and preparation method thereof

Abstract

The invention discloses low-temperature coagulation-accelerating anion styrene-butadiene latex for oil field well cementation and a preparation method of the low-temperature coagulation-accelerating anion styrene-butadiene latex. The low-temperature coagulation-accelerating anion styrene-butadiene latex comprises the following components in parts by mass: 100 parts of anion styrene-butadiene latex raw stock; 4 to 10 parts of a nonionic surfactant I; 2 to 4 parts of a nonionic surfactant II; 10 to 20 parts of water glass; 0.5 to 1 part of a defoaming agent; and 15-20 parts of deionized water. The low-temperature coagulation-accelerating anionic styrene-butadiene latex prepared by the invention is used in cement paste, has short thickening time at low temperature, can resist sodium chloride brine to reach semi-saturation, and can effectively control the water loss of the cement paste, improve the anti-channeling performance of a cement paste system, reduce the elastic modulus of set cement, increase the density of the set cement and improve the stability of the set cement. Therefore, formation gas is effectively prevented from invading cement stone, and well cementation quality is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of latex anti-channeling agents for oil well cementing, and particularly relates to a low-temperature coagulation-promoting anionic styrene-butadiene latex for oilfield cementing and a preparation method thereof. Background Art

[0002] Styrene-butadiene latex cement has good gas channeling prevention performance and water loss reduction performance, can improve the flexural strength of the cement stone and reduce the elastic modulus of the cement stone; since the latex particles are generally between 50-200 nm, the compactness and impermeability of the cement slurry are further increased, and the corrosion resistance of the cement stone to hydrogen sulfide and carbon dioxide can be improved. According to the types of emulsifiers used, the latex can be divided into cationic latex, anionic latex and non-ionic latex. With the construction of air compression energy storage reservoirs, salt cavern gas storage reservoirs, etc., high requirements are put forward for the anti-channeling performance of the cement slurry for cementing and the toughness of the subsequent cement stone. At present, the latex used in oilfield cementing is basically anionic, and the latex cement slurry generally needs to be used in combination with an AMPS polymer water loss reducer, resulting in too long thickening time of the cement slurry at low temperature, and due to the ionic sensitivity of the anionic styrene-butadiene latex itself, it is easy to react with cations such as calcium and aluminum in the cement slurry system, resulting in demulsification and affecting the safety of the cementing construction. Summary of the Invention

[0003] The purpose of the present invention is to provide a low-temperature coagulation-promoting anionic styrene-butadiene latex for oilfield cementing and a preparation method thereof. The anionic styrene-butadiene latex prepared by the present invention has low ionic sensitivity to the ions in the cement slurry, low water loss reduction amount of the controlled cement slurry, can resist sodium chloride brine to reach semi-saturation, and can prevent gas channeling. This product has low cost and simple preparation, and is a kind of economic and environment-friendly cementing material.

[0004] In order to solve the above technical problems, the technical solution provided by the present invention is as follows:

[0005] In the first aspect, the present invention provides a low-temperature coagulation-promoting anionic styrene-butadiene latex for oilfield cementing, which comprises the following components in parts by mass:

[0006] 100 parts of anionic styrene-butadiene latex raw slurry;

[0007] 4-10 parts of non-ionic surfactant I;

[0008] 2-4 parts of non-ionic surfactant II;

[0009] 10-20 parts of water glass;

[0010] 0.5-1 part of defoaming agent;

[0011] 15-20 parts of deionized water.

[0012] Further,

[0013] The mass solid content in the original anionic styrene-butadiene latex is 40-43%, the viscosity is 35 mPa·s - 45 mPa·s, and the pH value is 6-8.

[0014] Furthermore,

[0015] The molecular structure of the non-ionic surfactant I contains C 7 -C 13 alkyl, -C 6 H 5 and -O(CH 2 CH 2 ) n , where n is an integer from 13 to 20.

[0016] Furthermore,

[0017] The molecular structure of the non-ionic surfactant II contains C 7 -C 13 alkyl, -C 6 H 5 and -O(CH 2 CH 2 ) n , where n is an integer from 20 to 60.

[0018] Furthermore,

[0019] The modulus of the sodium silicate is 2.6 - 2.9, the mass fraction of silicon dioxide > 25.7%, and the density is 1.436 - 1.465 g / cm 3 .

[0020] Furthermore,

[0021] The defoamer is a silicone-oxygen copolymer and a phosphate ester.

[0022] Furthermore,

[0023] The silicone-oxygen copolymer contains a structure of -Si-O and -CH 3 .

[0024] Furthermore,

[0025] The low-temperature coagulation-promoting anionic styrene-butadiene latex for oilfield well cementing comprises the following components by mass: 100 parts of the original anionic styrene-butadiene latex, 4 - 10 parts of the non-ionic surfactant I, 2 - 4 parts of the non-ionic surfactant II, 10 - 20 parts of the sodium silicate, 0.5 - 1 part of the defoamer, and 15 - 20 parts of deionized water;

[0026] Among them, non-ionic surfactant I is octylphenol polyoxyethylene ether with a polymerization degree of 15; non-ionic surfactant II is octylphenol polyoxyethylene ether with a polymerization degree of 40; the modulus of sodium silicate is 2.6 - 2.9, the mass fraction of silicon dioxide > 25.7%, and the mass fraction of sodium oxide ≥ 10.2%; the defoamer is a silicone copolymer and tributyl phosphate.

[0027] In a second aspect, the present invention provides a method for preparing the low-temperature coagulation-promoting anionic styrene-butadiene latex for oilfield cementing. Non-ionic surfactant I, non-ionic surfactant II, sodium silicate, and deionized water are sequentially added to a reaction kettle, heated to a first temperature, and stirred at a constant temperature until the mixture is completely dissolved. Then, the heater of the reaction kettle is turned off, and when the temperature of the kettle body drops to a second temperature, the anionic styrene-butadiene latex stock solution and the defoamer are added, and stirring is continued to prepare the low-temperature coagulation-promoting anionic styrene-butadiene latex for oilfield cementing.

[0028] Furthermore,

[0029] The first temperature is 60 - 70 °C;

[0030] The second temperature is 25 - 30 °C.

[0031] Based on the above technical solutions, the technical effects that the present invention can achieve are as follows:

[0032] (1) The present invention uses two non-ionic surfactants and sodium silicate to improve the stability of the anionic styrene-butadiene latex stock solution. On the one hand, adding long-chain alkylphenol polyoxyethylene ether can enhance the ability to resist divalent cations such as calcium and magnesium and alkalinity; on the other hand, adding sodium silicate can form silicate ions, forming a double electric layer on the surface of the latex particles, improving the stability of the styrene-butadiene latex, and the silicate ions participate in the reaction during the cement hydration process, shortening the thickening time, and further improving the performance of the cement slurry at low temperatures.

[0033] (2) Adding this anionic styrene-butadiene latex to the cement slurry can not only shorten the thickening time, but also improve the anti-channeling performance of the cement slurry system and enhance the elasticity of the cement stone;

[0034] (3) This preparation method is simple, has low requirements for equipment, and the prepared anionic styrene-butadiene latex is suitable for low-temperature shallow well cementing operations. At the same time, it can increase the toughness of the cement stone and reduce the shrinkage rate of the cement stone. Specific Embodiments

[0035] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the following further elaborates on the present invention in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. That is, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0036] Accordingly, the following detailed description of the provided embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0037] Unless otherwise specified, the experimental methods used in the following embodiments are all conventional methods; the reagents, materials, etc. used in the following embodiments can all be obtained from commercial sources unless otherwise specified.

[0038] The low-temperature coagulation-promoting anionic styrene-butadiene latex for oilfield cementing of the present invention comprises the following components in parts by mass: 100 parts of anionic styrene-butadiene latex raw slurry, 4 - 10 parts of non-ionic surfactant I, 2 - 4 parts of non-ionic surfactant II, 10 - 20 parts of water glass, 0.5 - 1 part of defoamer, and 15 - 20 parts of deionized water.

[0039] The mass solid content in the anionic styrene-butadiene latex raw slurry is 40 - 43%, the viscosity is 35 mPa·s - 45 mPa·s, and the pH value is 6 - 8.

[0040] The molecular structure of non-ionic surfactant I contains an alkyl group of C 7 -C 13 , -C 6 H 5 and -O(CH 2 CH 2 )n, where n is an integer from 13 to 20.

[0041] The molecular structure of non-ionic surfactant II contains an alkyl group of C 7 -C 13 , -C 6 H 5 and -O(CH 2 CH 2 )n, where n is an integer from 20 to 60.

[0042] The modulus of the water glass is 2.6 - 2.9, the mass fraction of silicon dioxide > 25.7%, the mass fraction of sodium oxide ≥ 10.2%, and the density is 1.436 - 1.465 g / cm 3 .

[0043] The defoamer is a silicone-oxygen copolymer and tributyl phosphate, and the silicone-oxygen copolymer contains a structure of -Si-O and -CH 3 .

[0044] By mass, it includes the following components: 100 parts of anionic styrene-butadiene latex stock solution, 5 - 10 parts of non-ionic surfactant I, 2 - 4 parts of non-ionic surfactant II, 10 - 20 parts of water glass, and 0.5 - 1 part of defoamer; wherein surfactant I is octylphenol polyoxyethylene ether with a polymerization degree of 15; surfactant II is octylphenol polyoxyethylene ether with a polymerization degree of 40; the modulus of water glass is 2.6 - 2.9, the mass fraction of silicon dioxide > 25.7%, and the mass fraction of sodium oxide ≥ 10.2%; the defoamer is a silicone-oxygen copolymer and tributyl phosphate.

[0045] Preparation method of a low-temperature coagulation-promoting anionic styrene-butadiene latex for oilfield well cementing. Add water, non-ionic surfactant I, non-ionic surfactant II, and water glass into the reaction kettle in corresponding proportions in sequence, heat up to 60 - 70 °C, stir constantly at a constant temperature until all the mixtures are dissolved, then turn off the heater of the reaction kettle. When the temperature of the kettle body drops to 25 - 30 °C, add the anionic latex stock solution and defoamer, and continue to stir for 1 h to prepare the low-temperature coagulation-promoting anionic styrene-butadiene latex for oilfield well cementing.

[0046] The anionic styrene-butadiene latex used in the present invention has a Zeta potential of -30—-50 mV and a latex particle size of 50 - 200 nm, which is 1 / 200—1 / 100 of the particle size of oil well cement particles. It can fill the pores of the formed cement stone, making the cement stone more dense and further reducing the permeability of the cement stone. On the other hand, under the action of differential pressure, the latex particles aggregate into a non-permeable membrane between the cement particles, further reducing the water loss of the cement slurry.

[0047] The non-ionic surfactants I and II used in the present invention play the role of divalent cations such as calcium and magnesium generated during the hydration process of the cement slurry and the ability to resist alkalinity, preventing the demulsification of styrene-butadiene latex and resulting in flash setting of the cement slurry. The present invention adds water glass to form a negative ion double electric protection layer for the styrene-butadiene latex particles in the latex system to avoid the destruction of the latex by polyvalent positive ions Ca 2+ 、Al 3+ In addition, adding water glass can shorten the thickening time of the cement slurry, shorten the transition time of the cement slurry thickening, and further improve the gas channeling prevention performance of the cement slurry.

[0048] The low-temperature coagulation-promoting anionic styrene-butadiene latex prepared by the present invention has a short thickening time at low temperature when used in the cement slurry, is resistant to sodium chloride brine up to half saturation, and can effectively control the water loss of the cement slurry, improve the gas channeling prevention performance of the cement slurry system, reduce the elastic modulus of the cement stone, and increase the density of the cement stone, thereby effectively preventing formation gas from invading the cement stone and ensuring the well cementing quality.

[0049] Due to the addition of surfactants in styrene-butadiene latex, a large number of bubbles will be generated during the preparation process. Therefore, adding silicone-oxygen copolymer and tributyl phosphate can inhibit the generation of foam and has the function of defoaming at the same time. The anionic styrene-butadiene latex stock solution involved in the present invention is a styrene-butadiene latex for well cementing produced by Xinxiang Rixin Chemical Co., Ltd.

[0050] The following further elaborates with examples. The numbers in parentheses represent the degree of polymerization. The thickening experiment of the latex for well cementing prepared in the present invention in oil well cement is carried out on a high-temperature and high-pressure thickening instrument. First, prepare the latex cement slurry according to the GB / T19139-2012 standard. The composition of the cement slurry is: 800 g of G-grade cement, 64 g of styrene-butadiene latex (prepared), 24 g of fluid loss reducer BH-F201L, 280 g of deionized water, and 6 g of special defoamer BH-XP901L for latex. Among them, the G-grade cement is produced by Shandong Huayin Cement Factory, and BH-F201L and BH-XP901L are produced by Bohai Drilling Engineering Co., Ltd. Thickening conditions: thickening temperature is 40 °C, thickening pressure is 20 MPa, and the heating-up time is 10 min.

[0051] Example 1

[0052] Add 4 parts of non-ionic surfactant octylphenol polyoxyethylene ether (15), 2 parts of non-ionic surfactant octylphenol polyoxyethylene ether (40), x parts of water glass, and 20 parts of deionized water to the reaction kettle in the corresponding proportions in sequence. Heat up to 60 °C and stir constantly at a constant temperature until all the mixtures are dissolved. Then turn off the heater of the reaction kettle. When the temperature of the kettle body drops to between 25 - 30 °C, add 100 parts of anionic latex stock solution and 0.5 part of defoamer, and continue to stir for 1 h to prepare the finished product of anionic styrene-butadiene latex JR-1. The performance of the cement slurry is shown in Table 1.

[0053] The modulus of the water glass is 2.6, the mass fraction of silicon dioxide is 26.2%, and the density is 1.465 g / cm 3 .

[0054] According to the addition amount in Example 1, where the addition amount of water glass < 10 parts or > 20 parts, it is used as Comparative Example 1.

[0055] As can be seen from Table 1, after the prepared styrene-butadiene latex JR-1 is added to the cement slurry, the initial consistency, the sudden change value of the thickening line type of the cement slurry with the addition amount of x parts of water glass (x is 10 - 20) are normal, and the transition time is ≤ 10 min. The compressive strength of the cement stone > 20 MPa, and the elastic modulus is ≤ 5.6 GPa, and the permeability is 0.01×10 -3 μm 2, it meets the requirements of volume fracturing. When the addition amount of sodium silicate is < 10 parts during the preparation of styrene-butadiene latex, during the thickening process of the cement slurry, the stability is poor and phenomena such as bulging appear in the thickening curve; when the addition amount of sodium silicate is > 20 parts, the latter shows that due to the excessive amount of sodium silicate, the cement slurry is too thick.

[0056] Table 1 Cement properties of the cement incorporated with the formula JR-1 of Example 1 and the cement properties of the cement incorporated with the formula of Comparative Example 1

[0057] Example 2

[0058] Add 7 parts of non-ionic surfactant octylphenol polyoxyethylene ether (15), 3 parts of non-ionic surfactant octylphenol polyoxyethylene ether (40), x parts of sodium silicate and 20 parts of deionized water into the reaction kettle in corresponding proportions in sequence, heat up to 60 °C, stir at a constant temperature until all the mixtures are dissolved, then turn off the heater of the reaction kettle, when the temperature of the kettle body drops to between 25 - 30 °C, add 100 parts of anionic latex stock solution and 0.5 part of defoamer, and continue to stir for 1 h to prepare the finished product of anionic styrene-butadiene latex JR-2.

[0059] The modulus of the sodium silicate is 2.7, the mass fraction of silicon dioxide is 27.2%, and the density is 1.445 g / cm 3 .

[0060] According to the addition amount of Example 2, where the addition amount of sodium silicate is < 10 parts or > 20 parts, it is used as Comparative Example 2.

[0061] The properties of the cement slurry are shown in Table 2. It can be seen from Table 2 that after the prepared styrene-butadiene latex JR-2 is added to the cement slurry, for the cement slurry with the addition amount of sodium silicate being x parts (x is 10 - 20), the initial consistency, the mutation value of the thickening line type of the cement slurry are all normal, and the transition time is ≤ 10 min, the compressive strength of the cement stone is > 23 MPa, and the elastic modulus is ≤ 6.0 GPa, and the permeability is 0.01 × 10 -3 μm 2 , it meets the requirements of volume fracturing. When the addition amount of sodium silicate is < 10 parts during the preparation of styrene-butadiene latex, during the thickening process of the cement slurry, the stability is poor and phenomena such as bulging appear in the thickening curve; when the addition amount of sodium silicate is > 20 parts, the latter shows that due to the excessive amount of sodium silicate, the cement slurry is too thick.

[0062] Table 2 Cement properties of the cement incorporated with the formula JR-2 of Example 2 and the cement properties of the cement incorporated with the formula of Comparative Example 2

[0063] Example 3

[0064] Add 10 parts of non-ionic surfactant octylphenol polyoxyethylene ether (15), 4 parts of non-ionic surfactant octylphenol polyoxyethylene ether (40), x parts of water glass and 20 parts of deionized water into the reaction kettle in sequence according to the corresponding proportions, heat up to 60 °C, stir at a constant temperature until the mixture is completely dissolved, then turn off the reaction kettle heater. When the temperature of the kettle body drops to between 25 - 30 °C, add 100 parts of anionic latex stock solution and 0.5 part of defoamer, and continue to stir for 1 h to prepare the finished anionic styrene-butadiene latex JR-3.

[0065] The modulus of the water glass is 2.9, the mass fraction of silicon dioxide is 28.2%, and the density is 1.436 g / cm 3 。

[0066] According to the addition amount in Example 3, where the addition amount of water glass < 10 parts or > 20 parts, it is used as Comparative Example 3.

[0067] The properties of the cement slurry are shown in Table 3. It can be seen from Table 3 that after the prepared styrene-butadiene latex JR-3 is added to the cement slurry, the initial consistency and the sudden change value of the thickening line type of the cement slurry with the addition amount of water glass being x parts (x is 10 - 20) are normal, and the transition time is ≤ 10 min. The compressive strength of the cement stone > 20 MPa, and the elastic modulus is ≤ 5.9 GPa, and the permeability is 0.01 × 10 -3 μm 2 ,meeting the requirements of volume fracturing. When the addition amount of water glass < 10 parts during the preparation of the styrene-butadiene latex, the stability of the cement slurry is poor during the thickening process, and phenomena such as bulging appear in the thickening curve; when the addition amount of water glass > 20 parts, the latter shows that due to the excessive amount of water glass, the cement slurry is too thick.

[0068] Table 3 Cement properties of the cement slurry doped with the JR-3 formula of Example 3 and the cement properties of the formula of Comparative Example 3

[0069] Comparative Example 4

[0070] Add 7 parts of non-ionic surfactant octylphenol polyoxyethylene ether (15), 15 parts of water glass and 20 parts of deionized water into the reaction kettle in sequence according to the corresponding proportions, heat up to 60 °C, stir at a constant temperature until the mixture is completely dissolved, then turn off the reaction kettle heater. When the temperature of the kettle body drops to between 25 - 30 °C, add 100 parts of anionic latex stock solution and 0.5 part of defoamer, and continue to stir for 1 h to prepare the finished anionic styrene-butadiene latex JR-1'.

[0071] The modulus of the water glass is 2.7, the mass fraction of silicon dioxide is 27.2%, and the density is 1.445 g / cm 3 。

[0072] Comparative Example 5

[0073] Add 3 parts of non-ionic surfactant octylphenol polyoxyethylene ether (40), 15 parts of water glass and 20 parts of deionized water into the reaction kettle in corresponding proportions in sequence, stir at a constant temperature until the mixture is completely dissolved, then turn off the heater of the reaction kettle. When the temperature of the kettle body drops to between 25-30 °C, add 100 parts of anionic latex stock solution and 0.5 part of defoamer, and continue to stir for 1 h to prepare the finished product of anionic styrene-butadiene latex JR-2'.

[0074] The modulus of the water glass is 2.7, the mass fraction of silicon dioxide is 27.2%, and the density is 1.445 g / cm 3 。

[0075] The performance of the cement slurry in the comparative example is shown in Table 4. It can be seen from Table 4 that after the styrene-butadiene latex prepared according to the comparative example is added to the cement slurry, the initial consistency and the sudden change value of the thickening line type of the cement slurry both meet the construction requirements. However, the stability of the cement slurry is slightly poor, and the anti-channeling performance of the cement slurry becomes worse. The transition time of the cement slurry is > 20 min. Compared with the examples, the compressive strength of the cement stone is < 20 MPa, and the elastic modulus is > 6 GPa, and the permeability increases, which does not meet the requirements of volume fracturing.

[0076] Table 4 Performance of Cement Slurry Containing Latex in Comparative Example at 40 °C

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A low-temperature accelerating anionic styrene-butadiene latex for oil field cementing, It is characterized in that The components include the following in parts by mass: 100 parts of anionic styrene-butadiene latex stock; Nonionic surfactant I 4-10 parts; Nonionic surfactant II 2-4 parts; 10-20 parts of water glass; Defoaming agent 0.5-1 part; 15-20 parts of deionized water.

2. The low-temperature accelerating anionic styrene-butadiene latex for oil field cementing according to claim 1, It is characterized in that The anionic styrene-butadiene latex stock slurry has a mass solid content of 40-43%, a viscosity of 35 mPa·s-45 mPa·s, and a pH value of 6-8.

3. The low-temperature accelerating anionic styrene-butadiene latex for oil field cementing according to claim 1, It is characterized in that The molecular structure of the nonionic surfactant I contains C 7 -C 13 Alkyl, -C 6 H 5 and -O(CH 2 CH 2 ) n , n is an integer from 13 to 20.

4. The low-temperature accelerating anionic styrene-butadiene latex for oil field cementing according to claim 1, It is characterized in that The molecular structure of the nonionic surfactant II contains C 7 -C 13 Alkyl, -C 6 H 5 and -O(CH 2 CH 2 ) n , n is an integer from 20 to 60.

5. The low-temperature accelerating anionic styrene-butadiene latex for oil field cementing according to claim 1, It is characterized in that The modulus of the water glass is 2.6-2.9, the mass fraction of silicon dioxide is greater than 25.7%, the mass fraction of sodium oxide is greater than 10.2%, and the density is 1.436-1.465 g / cm 3 .

6. The low-temperature accelerating anionic styrene-butadiene latex for oil field cementing according to claim 1, It is characterized in that The defoaming agent is a silicone copolymer and a phosphate ester.

7. The low-temperature accelerating anionic styrene-butadiene latex for oil field cementing according to claim 6, It is characterized in that Silicon-oxygen copolymers contain -Si-O and -CH 3 structure.

8. The low-temperature accelerating anionic styrene-butadiene latex for oil field cementing according to claim 1, It is characterized in that The composition includes the following components by weight: 100 parts of anionic styrene-butadiene latex stock, 4-10 parts of nonionic surfactant I, 2-4 parts of nonionic surfactant II, 10-20 parts of water glass, 0.5-1 parts of defoaming agent, and 15-20 parts of deionized water; The nonionic surfactant I is octylphenol polyoxyethylene ether with a polymerization degree of 15; the nonionic surfactant II is octylphenol polyoxyethylene ether with a polymerization degree of 40; the modulus of water glass is 2.6-2.9, the mass fraction of silicon dioxide is greater than 25.7%, and the mass fraction of sodium oxide is greater than or equal to 10.2%; and the defoaming agent is a silicon-oxygen copolymer and tributyl phosphate.

9. A method for preparing the low-temperature accelerating anionic styrene-butadiene latex for oil field cementing according to any one of claims 1 to 8, It is characterized in that Nonionic surfactant I, nonionic surfactant II, water glass and deionized water are added into a reactor in sequence, the temperature is raised to a first temperature, and the mixture is stirred at a constant temperature until all the mixture is dissolved. Then, the heater of the reactor is turned off, and the temperature of the reactor body is reduced to a second temperature. Then, anionic styrene-butadiene latex slurry and a defoaming agent are added, and stirring is continued to prepare a low-temperature accelerating coagulation anionic styrene-butadiene latex for oil field cementing.

10. The preparation method according to claim 9, It is characterized in that The first temperature is 60-70°C; The second temperature is 25-30°C.

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