A hydrocarbon carbon dioxide gas-soluble foaming agent composition and preparation method thereof

Abstract

The present invention belongs to the technical field of carbon sequestration and utilization, and specifically provides a hydrocarbon carbon dioxide gas-soluble foaming agent composition and a preparation method thereof, wherein the hydrocarbon carbon dioxide gas-soluble foaming agent composition comprises: 0.2-0.5% gas-soluble main agent, 0.1-0.3% gas-soluble promoter, and 0.3-1.0% gas-soluble stabilizer. The hydrocarbon carbon dioxide gas-soluble foaming agent composition has low cost, no biological toxicity, good gas solubility, and good foam stability; and has a simple composition and an easy preparation process. The composition can be adjusted in time according to the temperature, pressure, and mineralization conditions of the oil reservoir, saving costs and achieving the best effect.

Description

Technical Field

[0001] The present invention belongs to the technical field of carbon sequestration and utilization, and in particular relates to a hydrocarbon carbon dioxide gas-soluble foaming agent composition and a preparation method thereof. Background Art

[0002] CO 2 Gas-soluble foam refers to the foam formed when the gas-soluble foaming agent is dissolved in supercritical carbon dioxide and enters the oil reservoir, and contacts with formation water and the shearing action of the porous medium of the reservoir. The key to this technology is that the gas-soluble foaming agent can be carried by supercritical carbon dioxide. Even if the foam breaks and fails, it can continue to penetrate deep into the reservoir with carbon dioxide and generate foam again after contacting formation water. This characteristic can not only achieve deep sweep and oil displacement adjustment, but also effectively improve crude oil recovery. In the process of foam generation, the original formation water is consumed, and CO 2 The gas-soluble foam technology provides a larger space capacity for storage. In addition, since the injection process of the gas-soluble foam is equivalent to gas injection rather than direct foam injection, it is easier to enter the reservoir and avoids the difficulties caused by excessive injection resistance. In this way, the gas-soluble foam technology provides an effective solution for improving the efficiency of carbon dioxide storage and oil recovery.

[0003] The fatty alcohol polyoxyethylene polyoxypropylene ether and nonylphenol polyoxyethylene ether gas-soluble surfactants disclosed in Chinese patent CN103867169A have the problems of poor foam stability in the reservoir and low solubility in supercritical carbon dioxide. In addition, Chinese patents CN104774604A and CN105255473A disclose a fluorine-containing polyurethane gas-soluble foaming agent and a silicon-containing CO 2 Gas-soluble foaming agents, fluorine-containing and silicon-containing gas-soluble foaming agents, although their solubility and foam stability have been improved to a certain extent, still have the problems of complex synthesis process, high cost, high biological toxicity and unfriendly environment, and are difficult to be used for large-dose injection in tertiary oil recovery. Chinese patent CN114316939A discloses a carbon dioxide gas-soluble foaming agent composition, which is composed of a foaming agent main agent, a foam stabilizer, a foam promoter, a liquid film strengthener, an alkaline substance and a cosolvent; however, the composition of this gas-soluble foaming agent is complex and the preparation process is cumbersome. Even after adding a low-carbon alcohol cosolvent, the liquid film strengthener and the alkaline substance still cannot be dissolved in supercritical carbon dioxide; at the same time, although the cosolvent can promote the dissolution of the foaming agent main agent, the foam stabilizer and the foam promoter in supercritical carbon dioxide, it will significantly reduce the stability of the foam. In summary, the gas-soluble foaming agents currently proposed have limitations in terms of composition complexity, preparation cost, biological toxicity, foam stability and solubility in carbon dioxide. Summary of the invention

[0004] The present invention aims at the deficiencies of the existing carbon dioxide gas-soluble foaming agent and provides a hydrocarbon carbon dioxide gas-soluble foaming agent composition and a preparation method thereof. The hydrocarbon carbon dioxide gas-soluble foaming agent composition does not contain fluorocarbon and siloxane substances, so it is low in cost, non-biotoxic, environmentally friendly, and suitable for large-dose injection in tertiary oil recovery; each component single agent can be dissolved in supercritical carbon dioxide, and does not need to use low-carbon alcohol co-solvent to improve solubility, so it has good gas solubility and good foam stability; the composition is simple and the preparation process is easy; the composition can be adjusted in time according to the temperature, pressure, and salinity conditions of the oil reservoir, saving costs and achieving the best effect.

[0005] The technical solution of the present invention is as follows:

[0006] In order to achieve the above-mentioned object, the present invention provides a hydrocarbon carbon dioxide gas-soluble foaming agent composition, comprising: a gas-soluble main agent, a gas-soluble promoter, a gas-soluble stabilizer, and water.

[0007] Specifically, the hydrocarbon carbon dioxide gas-soluble foaming agent composition is composed of the following single agents in percentage by mass: 0.2-0.5% of a gas-soluble main agent, 0.1-0.3% of a gas-soluble promoter, 0.3-1.0% of a gas-soluble stabilizer, and the balance is water.

[0008] Furthermore, the gas-soluble main agent is polymethyl alcohol polyoxyethylene ether, and its molecular structure formula is:

[0009] ,

[0010] Wherein: R is any one of 3,5,5-trimethyl-1-hexyl, 2,3-dimethyl-2-heptyl, 2,4,4-trimethyl-1-pentyl, 2,2,4-trimethyl-3-pentyl, 3,4,5-trimethyl-4-heptyl, 3,4,4-trimethyl-3-pentyl, 2,3,4-trimethyl-3-pentyl, 2,3,3-trimethyl-2-pentyl, 2,4,6-trimethyl-4-heptyl, 2,4,4-trimethyl-2-pentyl, 2,6,6-trimethyl-4-heptynyl, 3,4,4-trimethyl-1-pentynyl, 3,4,4-trimethyl-1-pentenyl, 3-(tert-butyl)-2,2,4,4,-tetramethylpentyl, 2,3,3-trimethyl-2-butyl, and 3-methyl-2-butyl.

[0011] The value range of m is 5~15. The polyoxyethylene group is the main hydrophilic group in the aerosol main agent and the main foam stabilizing group. If the value range of m is lower than 5, the polyoxyethylene group is too short and cannot penetrate into the water phase at the gas-liquid interface to form a strong hydrogen bond with the water phase, which will lead to a thinner hydration film thickness and a weakened hydrogen bond between the surfactant molecules and the water phase, which will cause the foam liquid film to break easily and the foam stability to deteriorate. If the value range of m is higher than 15, the solubility of the aerosol surfactant in supercritical carbon dioxide will be lower than 0.3wt%. 2 The mass fraction of the carried aerosol surfactant is too low to form effective foam, making it difficult to achieve the purpose of oil displacement and sealing.

[0012] Furthermore, the aerosol promoter is polymethyl alcohol polyoxypropylene ether sulfonate, and its molecular structure is as follows:

[0013] ,

[0014] Wherein: R′ is any one of 3,5,5-trimethyl-1-hexyl, 2,3-dimethyl-2-heptyl, 2,4,4-trimethyl-1-pentyl, 2,2,4-trimethyl-3-pentyl, 3,4,5-trimethyl-4-heptyl, 3,4,4-trimethyl-3-pentyl, 2,3,4-trimethyl-3-pentyl, 2,3,3-trimethyl-2-pentyl, 2,4,6-trimethyl-4-heptyl, 2,4,4-trimethyl-2-pentyl, 2,6,6-trimethyl-4-heptyl, 3,4,4-trimethyl-1-pentynyl, 3,4,4-trimethyl-1-pentenyl, 3-(tert-butyl)-2,2,4,4,-tetramethylpentyl, 2,3,3-trimethyl-2-butyl, and 3-methyl-2-butyl.

[0015] The value of n ranges from 10 to 25. The polyoxypropylene group is the main CO-philic group in the aerosol accelerator. 2 If the value of n is less than 10, the solubility of the gas-soluble surfactant in supercritical carbon dioxide will be less than 0.2 wt%. 2 The mass fraction of the aerosol surfactant carried is too low to form effective foam; when the value of n is higher than 25, the polyoxypropylene blocks will spirally stack at the gas-liquid interface to form a rugby-shaped accumulation, thereby destroying the tightly arranged structure of the foam liquid film, reducing the elasticity and density of the foam liquid film, and CO 2 The molecules easily diffuse and penetrate through the liquid membrane, which will cause the foam formed by the aerosol surfactant to have a short half-life and extremely poor stability, making it impossible to achieve the purpose of effective oil displacement and sealing.

[0016] The aerosol-soluble promoter can be used as anionic and nonionic surfactants with the aerosol-soluble main agent respectively, and anionic-nonionic compounding can be achieved through different adsorption paths and interfacial forces, thereby reducing mutual repulsion, improving the tightness of molecular arrangement at the interface, forming a more stable gas-liquid interface, and thus enhancing the stability and anti-rupture performance of the foam. In addition, the aerosol-soluble promoter and the aerosol-soluble main agent achieve synergistic synergy, and the two jointly reduce interfacial tension, enhance the strength and uniformity of the liquid film, and significantly improve the foaming performance of the foam, so that it can better resist the harsh environment of high temperature, high salt, and high pH.

[0017] Furthermore, the gas-soluble stabilizer is a vinyl acetate-maleate alternating copolymer, and its molecular structure is as follows:

[0018] ,

[0019] The value range of y is 30 to 50. Vinyl acetate-maleate alternating copolymer mainly plays the role of foam stabilizer. If the value range of y is lower than 30, the polymer chain length will be too short and cannot be entangled with the gas-soluble main agent and the gas-soluble promoter to form a three-dimensional network structure to achieve efficient foam stabilization; if the value range of y is higher than 50, the polymer chain length will be too long, causing the polymer to be paste-like or even powdery, and the solubility in supercritical carbon dioxide is too low, and it also cannot play the role of foam stabilizer.

[0020] The polymer chain of the aerosol stabilizer is intertwined and entangled in the foam liquid film to form a three-dimensional network structure, thereby increasing the viscosity of the liquid film, increasing the viscoelasticity of the foam liquid film, thereby limiting the loss of liquid, slowing down the drainage process of the bubble, extending the survival time of the foam, and improving the shear resistance of the foam, making the foam more stable under dynamic conditions. In addition, the aerosol promoter and the aerosol main agent are both chain-flexible, long-branched surfactants, and have excellent compatibility with the aerosol stabilizer. Therefore, compared to other promoters and main agents, polymethyl alcohol polyoxyethylene ether and polymethyl alcohol polyoxypropylene ether sulfonate are used as aerosol main agents and aerosol promoters, respectively, which are more likely to form a stable three-dimensional network structure with the aerosol stabilizer.

[0021] Furthermore, the water is any one of distilled water, deionized water and mineralized water.

[0022] The present invention also provides a method for preparing the hydrocarbon carbon dioxide gas-soluble foaming agent composition, comprising the following steps:

[0023] Step 1, synthesis of polymethyl alcohol polyoxyethylene ether:

[0024] In a reaction kettle, polymethyl alcohol and an alkaline catalyst are added, and ethylene oxide is introduced after nitrogen purging for 10 to 15 minutes for 1 to 10 hours. The reaction temperature is controlled at 120 to 130 °C for 1 to 10 hours. After the reaction is completed, the temperature is lowered and the material is discharged to obtain a crude product of polymethyl alcohol polyoxyethylene ether; the crude product of polymethyl alcohol polyoxyethylene ether is neutralized by adding glacial acetic acid, washed with water, and evaporated in vacuo to obtain pure polymethyl alcohol polyoxyethylene ether.

[0025] The polymethyl alcohol is 3,5,5-trimethyl-1-hexanol, 2,3-dimethyl-2-heptanol, 2,4,4-trimethyl-1-pentanol, 2,2,4-trimethyl-3-pentanol, 3,4,5-trimethyl-4-heptanol, 3,4,4-trimethyl-3-pentanol, 2,3,4-trimethyl-3-pentanol, 2,3,3-trimethyl-2-pentanol, 2,4,6-trimethyl- One of 2,4,4-trimethyl-2-pentanol, 2,6,6-trimethyl-4-heptyn-3-ol, 3,4,4-trimethyl-1-pentyn-3-ol, 3,4,4-trimethyl-1-penten-3-ol, 3-(tert-butyl)-2,2,4,4,-tetramethylpentan-3-ol, 2,3,3-trimethyl-2-butanol, and 3-methyl-2-butanol.

[0026] The molar ratio of the polymethyl alcohol to ethylene oxide is 1:(5-15);

[0027] The alkaline catalyst is a mixture of one or more of calcium hydroxide, barium hydroxide and magnesium hydroxide;

[0028] The added mass of the alkaline catalyst is 1.0-2.5% of the total mass of the polymethyl alcohol and ethylene oxide.

[0029] Step 2: Synthesis of polymethyl alcohol polyoxypropylene ether sulfonate:

[0030] In a reaction kettle, polymethyl alcohol and an alkaline catalyst are added, propylene oxide is introduced after nitrogen purging for 10 to 15 minutes, and the introduction time is 1 to 10 hours. The reaction temperature is controlled at 120 to 130 ° C for 1 to 10 hours. After the reaction is completed, the temperature is lowered and the material is discharged to obtain a crude product of polymethyl alcohol polyoxypropylene ether; the crude product of polymethyl alcohol polyoxypropylene ether is neutralized by adding glacial acetic acid, washed with water, and evaporated in vacuum to obtain pure polymethyl alcohol polyoxypropylene ether;

[0031] Using water as solvent and ethanol as co-solvent, after adding polymethyl alcohol polyoxypropylene ether, a mixed sulfonating agent solution prepared by sodium sulfite and sodium bisulfite is added dropwise, and the mixture is stirred and reacted at 80-100°C for 4-8 hours until the solution becomes one phase; after cooling to room temperature, extraction, rotary evaporation, and recrystallization are performed to obtain polymethyl alcohol polyoxypropylene ether sulfonate.

[0032] The polymethyl alcohol is 3,5,5-trimethyl-1-hexanol, 2,3-dimethyl-2-heptanol, 2,4,4-trimethyl-1-pentanol, 2,2,4-trimethyl-3-pentanol, 3,4,5-trimethyl-4-heptanol, 3,4,4-trimethyl-3-pentanol, 2,3,4-trimethyl-3-pentanol, 2,3,3-trimethyl-2-pentanol, 2,4,6-trimethyl- One of 2,4,4-trimethyl-2-pentanol, 2,6,6-trimethyl-4-heptyn-3-ol, 3,4,4-trimethyl-1-pentyn-3-ol, 3,4,4-trimethyl-1-penten-3-ol, 3-(tert-butyl)-2,2,4,4,-tetramethylpentan-3-ol, 2,3,3-trimethyl-2-butanol, and 3-methyl-2-butanol.

[0033] The molar ratio of the polymethyl alcohol to propylene oxide is 1:(10-25);

[0034] The alkaline catalyst is a mixture of one or more of calcium hydroxide, barium hydroxide and magnesium hydroxide;

[0035] The added mass of the alkaline catalyst is 0.5-2.0% of the total mass of polymethyl alcohol and propylene oxide;

[0036] The molar ratio of the mixed sulfonating agent solution to the polymethyl alcohol polyoxypropylene ether is 1: (1-5);

[0037] The molar ratio of the sodium sulfite to the sodium bisulfite is 1:(1-5).

[0038] Step 3: Synthesis of vinyl acetate-maleate alternating copolymer:

[0039] Add vinyl acetate and diethyl maleate in a 1:1 molar ratio to the reactor, then add toluene solvent. After the solvent is completely dissolved, add azobisisobutyronitrile (AIBN). Under nitrogen protection, seal the reactor, heat the reactor to 60-80°C, and keep stirring for 12-24 hours. When the temperature of the reactor drops to room temperature, pour in n-hexane for precipitation, rotary evaporate, filter, place in a high-pressure reactor, and pass CO 2 The mixture was purged and replaced for 3-6 h and then dried to obtain vinyl acetate-maleate alternating copolymer.

[0040] The volume of the toluene solvent is 70-90% of the total volume of vinyl acetate and diethyl maleate;

[0041] The mass of the azobisisobutyronitrile (AIBN) is 1-3% of the total mass of vinyl acetate and diethyl maleate.

[0042] Step 4: Preparation of hydrocarbon carbon dioxide gas-soluble foaming agent composition:

[0043] The polymethyl alcohol polyoxyethylene ether and the polymethyl alcohol polyoxypropylene ether sulfonate are mixed and stirred for 20 to 60 minutes, and then the vinyl acetate-maleate alternating copolymer is added and shaken for 1 to 2 hours to obtain a hydrocarbon carbon dioxide gas-soluble foaming agent composition.

[0044] Wherein, the gas-soluble stabilizer is added after the gas-soluble main agent and the gas-soluble promoter are fully mixed, so that the gas-soluble main agent and the gas-soluble promoter are physically mixed during the stirring process, thereby reducing the interfacial tension and improving the initial effect of foam generation. If the three are added at the same time, the gas-soluble stabilizer may directly interact with the gas-soluble main agent or the gas-soluble promoter, resulting in a weakened synergistic effect between molecules, which is not conducive to the optimal formation of the three-dimensional network structure of the stabilizer in the foam liquid film. In addition, the gas-soluble stabilizer has the effect of increasing the viscosity of the liquid film and enhancing the viscoelasticity. If it is added too early, it may interfere with the initial effect of the gas-soluble main agent and the gas-soluble promoter, causing the viscosity of the hydrocarbon carbon dioxide gas-soluble foaming agent composition to rise too quickly, hindering further mixing and gas-liquid interface adsorption process, resulting in reduced foaming efficiency or poor foam performance.

[0045] The hydrocarbon carbon dioxide gas-soluble foaming agent composition provided by the present invention includes a gas-soluble main agent, a gas-soluble promoter, and a gas-soluble stabilizer, and the composition composition can be adjusted in time according to the reservoir conditions. Among them, the main function of the gas-soluble main agent is to reduce the interfacial tension and form a stable foam. Under high temperature and high salinity environment, the hydrophobic tail of the gas-soluble main agent can be well expanded, and the contact area with the gas phase is increased, further reducing the interfacial tension; the main function of the gas-soluble promoter is to enhance the formation rate and initial stability of the foam. Under low temperature or low salinity conditions, the gas-soluble promoter increases the initial foaming rate and shortens the bubble generation time. At the same time, it also helps to maintain the stability of the foam under high pressure conditions; the gas-soluble stabilizer mainly forms a three-dimensional network structure to increase the viscosity and viscoelasticity of the foam liquid film, enhance the shear resistance and rupture resistance of the foam, and under high pressure or dynamic conditions, the gas-soluble stabilizer can form a stronger three-dimensional network structure to improve the strength of the foam liquid film.

[0046] The beneficial effects of the present invention include but are not limited to:

[0047] 1. The hydrocarbon carbon dioxide gas-soluble foaming agent composition provided by the present invention does not contain fluorocarbon and siloxane substances, so it is low in cost, non-biotoxic, environmentally friendly, and suitable for large-dose injection in tertiary oil recovery;

[0048] 2. The gas-soluble main agent, gas-soluble promoter and gas-soluble stabilizer provided by the present invention can be dissolved in supercritical carbon dioxide, and do not need to use low-carbon alcohol cosolvent to improve solubility. Therefore, the gas solubility is good and the foam stability is good;

[0049] 3. The hydrocarbon carbon dioxide gas-soluble foaming agent composition provided by the present invention has a simple composition and an easy preparation process. The composition can be adjusted in time according to the temperature, pressure and salinity conditions of the oil reservoir, thereby saving costs and achieving the best effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 This is the foam liquid film morphology of Example 1;

[0051] Figure 2 This is the foam liquid film morphology of Comparative Example 3. DETAILED DESCRIPTION

[0052] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0053] Example 1

[0054] The hydrocarbon carbon dioxide gas-soluble foaming agent composition of this embodiment uses 3,5,5-trimethyl-1-hexanol polyoxyethylene ether as a gas-soluble main agent, 2,4,4-trimethyl-2-pentanol polyoxypropylene ether sulfonate as a gas-soluble promoter, and vinyl acetate-maleate-30 alternating copolymer as a gas-soluble stabilizer, wherein:

[0055] The molecular structure of 3,5,5-trimethyl-1-hexanol polyoxyethylene ether is:

[0056] ;

[0057] The molecular structure of 2,4,4-trimethyl-2-pentanol polyoxypropylene ether sulfonate is:

[0058] ;

[0059] The molecular structure of vinyl acetate-maleate-30 alternating copolymer is:

[0060] .

[0061] The preparation method of the hydrocarbon carbon dioxide gas-soluble foaming agent composition of this embodiment is:

[0062] Step 1, synthesis of 3,5,5-trimethyl-1-hexanol polyoxyethylene ether:

[0063] In a high-pressure stainless steel reactor equipped with a stirring, heating and cooling system, 1.0 mol (144 g) of 3,5,5-trimethyl-1-hexanol and 7.9 g of barium hydroxide catalyst were added, and high-purity nitrogen (purity greater than 99.999%) was purged for 13 minutes, and then 9 mol (396 g) of ethylene oxide was introduced, and the reaction temperature was controlled at 120 ° C for 6.5 hours to obtain a crude product of 3,5,5-trimethyl-1-hexanol polyoxyethylene ether, and the temperature was lowered to discharge the material. The crude product of 3,5,5-trimethyl-1-hexanol polyoxyethylene ether was neutralized with glacial acetic acid, vacuum filtered, dissolved and filtered in ethyl acetate, rotary evaporated and vacuum dried to obtain 3,5,5-trimethyl-1-hexanol polyoxyethylene ether.

[0064] Step 2: Synthesis of 2,4,4-trimethyl-2-pentanol polyoxypropylene ether sulfonate:

[0065] In a high-pressure stainless steel reactor equipped with a stirring, heating and cooling system, 1.0 mol (130 g) of 2,4,4-trimethyl-2-pentanol and 7.9 g of barium hydroxide catalyst were added, and 13 mol (754 g) of propylene oxide was introduced after purging with high-purity nitrogen for 13 minutes. The reaction temperature was controlled at 130 °C for 6.5 hours to obtain a crude product of 2,4,4-trimethyl-2-pentanol polyoxypropylene ether, and the temperature was lowered to discharge the material. The crude product of 2,4,4-trimethyl-2-pentanol polyoxypropylene ether was neutralized with glacial acetic acid, vacuum filtered, dissolved and filtered with ethyl acetate, rotary evaporated and vacuum dried to obtain 2,4,4-trimethyl-2-pentanol polyoxypropylene ether.

[0066] With 30 mL of water as solvent and 30 mL of ethanol as cosolvent, add 2,4,4-trimethyl-2-pentanol polyoxypropylene ether into a three-necked flask, dropwise add a mixed sulfonating agent solution prepared by 12.6 g of sodium sulfite and 10.4 g of sodium bisulfite, and stir at 85 ºC for 5 h until the solution becomes one phase to obtain a light yellow liquid. After cooling to room temperature, add isopropanol for extraction, extract the upper layer of extract with dichloromethane, and remove dichloromethane by rotary evaporation to obtain a yellow liquid. The yellow liquid is recrystallized three times with ethanol and dried to obtain a white powdery solid 2,4,4-trimethyl-2-pentanol polyoxypropylene ether sodium sulfonate.

[0067] Step 3: Synthesis of vinyl acetate-maleate-30 alternating copolymer:

[0068] In a high-pressure reactor equipped with stirring, condensation reflux, temperature control and nitrogen protection, 484.8 mL of diethyl maleate (3 mol) with a mass concentration of 1.064 g / mL, 318.6 mL of vinyl acetate (3 mol) with a mass concentration of 0.81 g / mL, 9 g of AIBN, and 600 mL of toluene were added. The reaction was frozen, vacuumized, and filled with nitrogen three times. The reactor was sealed and the reaction temperature was controlled at 75 °C for 24 h. After the temperature was lowered to room temperature, it was poured into n-hexane for precipitation. After rotary evaporation, it was separated by suction filtration, and CO was introduced into the autoclave. 2 The purge was carried out for 3 h using 10 MPa CO 2 The low-volatile small molecules were taken out, and then vacuum dried at 40 °C to constant weight to obtain vinyl acetate-maleate-30 alternating copolymer.

[0069] Step 4: Preparation of hydrocarbon carbon dioxide gas-soluble foaming agent composition:

[0070] According to the mass percentage in Table 1, the above-mentioned 3,5,5-trimethyl-1-hexanol polyoxyethylene ether and 2,4,4-trimethyl-2-pentanol polyoxypropylene ether sulfonate were mixed and added to 99.3 g of distilled water, and stirred continuously for 45 minutes using a magnetic stirrer. Then, vinyl acetate-maleate-30 alternating copolymer was added, and the mixture was oscillated for 1.5 hours using an ultrasonic oscillator to obtain a hydrocarbon carbon dioxide gas-soluble foaming agent composition.

[0071] Table 1 Composition of hydrocarbon carbon dioxide gas-soluble foaming agent composition

[0072] composition substance Mass percentage Aerosol main agent 3,5,5-Trimethyl-1-hexanol polyoxyethylene ether 0.25% Aerosol accelerator Sodium 2,4,4-trimethyl-2-pentanol polyoxypropylene ether sulfonate 0.15% Aerosol stabilizer Vinyl acetate-maleate-30 alternating copolymer 0.30% water Distilled water margin

[0073] Example 2

[0074] This embodiment uses 2,4,4-trimethyl-1-pentanol polyoxyethylene ether as the gas-soluble main agent, 2,3,3-trimethyl-2-butanol polyoxypropylene ether sulfonate as the gas-soluble promoter, and vinyl acetate-maleate-35 alternating copolymer as the gas-soluble stabilizer, wherein:

[0075] The molecular structure of 2,4,4-trimethyl-1-pentanol polyoxyethylene ether is:

[0076] ;

[0077] The molecular structure of 2,3,3-trimethyl-2-butanol polyoxypropylene ether sulfonate is:

[0078] ;

[0079] The molecular structure of vinyl acetate-maleate-35 alternating copolymer is:

[0080] .

[0081] The preparation method of the hydrocarbon carbon dioxide gas-soluble foaming agent composition of this embodiment is:

[0082] Step 1, Synthesis of 2,4,4-trimethyl-1-pentanol polyoxyethylene ether:

[0083] In a high-pressure stainless steel reactor equipped with a stirring, heating and cooling system, 1.0 mol (130 g) of 2,4,4-trimethyl-1-pentanol and 14.1 g of calcium hydroxide catalyst were added, and high-purity nitrogen (purity greater than 99.999%) was purged for 11 minutes, and then 13 mol (572 g) of ethylene oxide was introduced, and the reaction temperature was controlled at 120 ° C for 5 hours to obtain a crude product of 2,4,4-trimethyl-1-pentanol polyoxyethylene ether, and the temperature was lowered to discharge the material. The crude product of 2,4,4-trimethyl-1-pentanol polyoxyethylene ether was neutralized with glacial acetic acid, vacuum filtered, dissolved and filtered in ethyl acetate, rotary evaporated and vacuum dried to obtain 2,4,4-trimethyl-1-pentanol polyoxyethylene ether.

[0084] Step 2: Synthesis of 2,3,3-trimethyl-2-butanol polyoxypropylene ether sulfonate:

[0085] In a high-pressure stainless steel reactor equipped with a stirring, heating and cooling system, 1.0 mol (116 g) of 2,3,3-trimethyl-2-butanol and 12.9 g of magnesium hydroxide catalyst were added, and 18 mol (1044 g) of propylene oxide was introduced after purging with high-purity nitrogen for 14 minutes. The reaction was completed in 8.0 hours, and the reaction temperature was controlled at 130 °C for 7.5 hours to obtain a crude product of 2,3,3-trimethyl-2-butanol polyoxypropylene ether, and the material was discharged after cooling. The crude product of 2,3,3-trimethyl-2-butanol polyoxypropylene ether was neutralized with glacial acetic acid, vacuum filtered, dissolved and filtered in ethyl acetate, rotary evaporated and vacuum dried to obtain 2,3,3-trimethyl-2-butanol polyoxypropylene ether.

[0086] With 40 mL of water as solvent and 30 mL of ethanol as cosolvent, add 2,3,3-trimethyl-2-butanol polyoxypropylene ether into a three-necked flask, dropwise add a mixed sulfonating agent solution prepared by 12.6 g of sodium sulfite and 20.4 g of sodium bisulfite, and stir at 85 ºC for 5 h until the solution becomes one phase to obtain a light yellow liquid. After cooling to room temperature, add isopropanol for extraction, extract the upper layer of the extract with dichloromethane, and remove dichloromethane by rotary evaporation to obtain a yellow liquid. Recrystallize the yellow liquid twice with ethanol and dry to obtain a white powdery solid 2,3,3-trimethyl-2-butanol polyoxypropylene ether sodium sulfonate.

[0087] Step 3, Synthesis of Vinyl Acetate-Maleate-35 Alternating Copolymer:

[0088] In a high-pressure reactor equipped with stirring, condensation reflux, temperature control and nitrogen protection, 565.6 mL of diethyl maleate (3.5 mol), 371.7 mL of vinyl acetate (3.5 mol), 10.2 g of AIBN, and 700 mL of toluene were added. The reactor was frozen, vacuumized, and filled with nitrogen three times. The reactor was sealed and the reaction temperature was controlled to be 75 °C for 24 h. After the temperature was lowered to room temperature, it was poured into n-hexane for precipitation. After rotary evaporation and separation by suction filtration, CO was introduced into the autoclave. 2 The purge was carried out for 6 h using 5 MPa CO 2 The small molecules that are not volatile are taken out and then dried in vacuum at 40 °C to constant weight.

[0089] Step 4: Preparation of hydrocarbon carbon dioxide gas-soluble foaming agent composition:

[0090] According to the mass percentage in Table 2, the above-mentioned 2,4,4-trimethyl-1-pentanol polyoxyethylene ether and 2,3,3-trimethyl-2-butanol polyoxypropylene ether sulfonate sodium were mixed and added to 98.85 g of distilled water, and stirred continuously for 50 minutes using a magnetic stirrer. Then, vinyl acetate-maleate-35 alternating copolymer was added, and the mixture was oscillated for 1.5 hours using an ultrasonic oscillator to obtain a hydrocarbon carbon dioxide gas-soluble foaming agent composition.

[0091] Table 2 Composition of hydrocarbon carbon dioxide gas-soluble foaming agent composition

[0092] composition substance Mass percentage Aerosol main agent 2,4,4-Trimethyl-1-pentanol polyoxyethylene ether 0.45% Aerosol accelerator Sodium 2,3,3-trimethyl-2-butanol polyoxypropylene ether sulfonate 0.20% Aerosol stabilizer Vinyl acetate-maleate-35 alternating copolymer 0.50% water Distilled water margin

[0093] Example 3

[0094] This embodiment uses 2,3-dimethyl-2-heptyl alcohol polyoxyethylene ether as the gas-soluble main agent, 2,2,4-trimethyl-3-pentanol polyoxypropylene ether sulfonate as the gas-soluble promoter, and vinyl acetate-maleate-40 alternating copolymer as the gas-soluble stabilizer, wherein:

[0095] The molecular structure of 2,3-dimethyl-2-heptanol polyoxyethylene ether is:

[0096] ;

[0097] The molecular structure of 2,2,4-trimethyl-3-pentanol polyoxypropylene ether sulfonate is:

[0098] ;

[0099] The molecular structure of vinyl acetate-maleate-40 alternating copolymer is:

[0100] .

[0101] The preparation method of the hydrocarbon carbon dioxide gas-soluble foaming agent composition of this embodiment is:

[0102] Step 1: Synthesis of 2,3-dimethyl-2-heptanol polyoxyethylene ether

[0103] In a high-pressure stainless steel reactor equipped with a stirring, heating and cooling system, 1.0 mol (144 g) of 2,3-dimethyl-2-heptanol and 8.1 g of calcium hydroxide catalyst were added, and high-purity nitrogen (purity greater than 99.999%) was purged for 13 minutes, and then 10 mol (440 g) of ethylene oxide was introduced, and the reaction temperature was controlled at 120 ° C for 6.5 hours to obtain a crude product of 2,3-dimethyl-2-heptanol polyoxyethylene ether, and the temperature was lowered to discharge the material. The crude product of 2,3-dimethyl-2-heptanol polyoxyethylene ether was neutralized with glacial acetic acid, vacuum filtered, dissolved and filtered in ethyl acetate, rotary evaporated and vacuum dried to obtain 2,3-dimethyl-2-heptanol polyoxyethylene ether.

[0104] Step 2: Synthesis of 2,2,4-trimethyl-3-pentanol polyoxypropylene ether sulfonate

[0105] In a high-pressure stainless steel reactor equipped with a stirring, heating and cooling system, 1.0 mol (130 g) of 2,2,4-trimethyl-3-pentanol and 6.1 g of barium hydroxide catalyst were purged with high-purity nitrogen for 10 min, and then 13 mol (754 g) of propylene oxide was introduced. The reaction was completed in 6.0 h, and the reaction temperature was controlled at 130 °C for 6.5 h to obtain a crude product of 2,2,4-trimethyl-3-pentanol polyoxypropylene ether, and the material was discharged after cooling. The crude product of 2,2,4-trimethyl-3-pentanol polyoxypropylene ether was neutralized with glacial acetic acid, vacuum filtered, dissolved and filtered with ethyl acetate, rotary evaporated and vacuum dried to obtain 2,2,4-trimethyl-3-pentanol polyoxypropylene ether.

[0106] With 60 mL of water as solvent and 60 mL of ethanol as cosolvent, add 2,2,4-trimethyl-3-pentanol polyoxypropylene ether into a three-necked flask, dropwise add a mixed sulfonating agent solution prepared by 15 g of sodium sulfite and 50 g of sodium bisulfite, and stir at 85 ºC for 5 h until the solution becomes one phase to obtain a light yellow liquid. After cooling to room temperature, add isopropanol for extraction, extract the upper extract with dichloromethane, and remove dichloromethane by rotary evaporation to obtain a yellow liquid. Recrystallize the yellow liquid with ethanol three times and dry to obtain a white powdery solid 2,2,4-trimethyl-3-pentanol polyoxypropylene ether sodium sulfonate.

[0107] Step 3: Synthesis of vinyl acetate-maleate-40 alternating copolymer

[0108] In a high-pressure reactor equipped with stirring, condensation reflux, temperature control and nitrogen protection, 646.4 mL of diethyl maleate (4 mol), 424.8 mL of vinyl acetate (4 mol), 12 g of AIBN, and 800 mL of toluene were added. The reactor was frozen, vacuumized, and filled with nitrogen three times. The reactor was sealed and the reaction temperature was controlled to be 75 °C for 24 h. After the temperature was lowered to room temperature, it was poured into n-hexane for precipitation. After rotary evaporation and separation by suction filtration, CO was introduced into the autoclave. 2 The purge was carried out for 4.5 h using 10 MPa CO 2 The small molecules that are not volatile are taken out and then dried in vacuum at 40 °C to constant weight.

[0109] Step 4: Preparation of hydrocarbon carbon dioxide gas-soluble foaming agent composition:

[0110] According to the mass percentage in Table 3, the above-mentioned 2,3-dimethyl-2-heptanol polyoxyethylene ether and 2,2,4-trimethyl-3-pentanol polyoxypropylene ether sulfonate were mixed and added to 98.9 g of distilled water, and stirred continuously for 55 minutes using a magnetic stirrer. Then, vinyl acetate-maleate-40 alternating copolymer was added, and the mixture was oscillated for 2 hours using an ultrasonic oscillator to obtain a hydrocarbon carbon dioxide gas-soluble foaming agent composition.

[0111] Table 3 Composition of hydrocarbon carbon dioxide gas-soluble foaming agent composition

[0112] composition substance Mass percentage Aerosol main agent 2,3-Dimethyl-2-heptanol polyoxyethylene ether 0.20% Aerosol accelerator Sodium 2,2,4-trimethyl-3-pentanol polyoxypropylene ether sulfonate 0.30% Aerosol stabilizer Vinyl acetate-maleate-40 alternating copolymer 0.60% water Distilled water margin

[0113] Example 4

[0114] This embodiment uses 3,4,4-trimethyl-3-pentanol polyoxyethylene ether as the gas-soluble main agent, 2,4,4-trimethyl-2-pentanol polyoxypropylene ether sulfonate as the gas-soluble promoter, and vinyl acetate-maleate-30 alternating copolymer as the gas-soluble stabilizer, wherein:

[0115] The molecular structure of 3,4,4-trimethyl-3-pentanol polyoxyethylene ether is:

[0116] ;

[0117] The molecular structure of 2,4,4-trimethyl-2-pentanol polyoxypropylene ether sulfonate is:

[0118] ;

[0119] The molecular structure of vinyl acetate-maleate-30 alternating copolymer is:

[0120] .

[0121] The preparation method of the hydrocarbon carbon dioxide gas-soluble foaming agent composition of this embodiment is:

[0122] Step 1, Synthesis of 3,4,4-trimethyl-3-pentanol polyoxyethylene ether:

[0123] In a high-pressure stainless steel reactor equipped with a stirring, heating and cooling system, 1.0 mol (130 g) of 3,4,4-trimethyl-3-pentanol and 7.2 g of barium hydroxide catalyst were purged with high-purity nitrogen (purity greater than 99.999%) for 11 minutes, and then 8 mol (352 g) of ethylene oxide was introduced. The reaction was completed in 5.5 hours, and the reaction temperature was controlled at 120 ° C for 4.5 hours to obtain a crude product of 3,4,4-trimethyl-3-pentanol polyoxyethylene ether, and the temperature was lowered to discharge the material. The crude product of 3,4,4-trimethyl-3-pentanol polyoxyethylene ether was neutralized with glacial acetic acid, vacuum filtered, dissolved and filtered in ethyl acetate, rotary evaporated and vacuum dried to obtain 3,4,4-trimethyl-3-pentanol polyoxyethylene ether.

[0124] Step 2: Synthesis of 2,4,4-trimethyl-2-pentanol polyoxypropylene ether sulfonate:

[0125] In a high-pressure stainless steel reactor equipped with a stirring, heating and cooling system, 1.0 mol (130 g) of 2,4,4-trimethyl-2-pentanol and 7.9 g of barium hydroxide catalyst were accurately weighed, and 15 mol (870 g) of propylene oxide was introduced after purging with high-purity nitrogen for 13 minutes. The reaction was completed in 6.0 hours, and the reaction temperature was controlled at 130 °C for 6.5 hours to obtain the crude product of 2,4,4-trimethyl-2-pentanol polyoxypropylene ether, and the material was discharged after cooling. The crude product of 2,4,4-trimethyl-2-pentanol polyoxypropylene ether was neutralized with glacial acetic acid, vacuum filtered, dissolved and filtered with ethyl acetate, rotary evaporated and vacuum dried to obtain 2,4,4-trimethyl-2-pentanol polyoxypropylene ether.

[0126] With 45 mL of water as solvent and 70 mL of ethanol as cosolvent, add 2,4,4-trimethyl-2-pentanol polyoxypropylene ether into a three-necked flask, dropwise add a mixed sulfonating agent solution prepared by 18 g of sodium sulfite and 54 g of sodium bisulfite, and stir at 85 ºC for 5 h until the solution becomes one phase to obtain a light yellow liquid. After cooling to room temperature, add isopropanol for extraction, extract the upper layer of extract with dichloromethane, and remove dichloromethane by rotary evaporation to obtain a yellow liquid. Recrystallize the yellow liquid with ethanol 5 times and dry to obtain a white powdery solid 2,4,4-trimethyl-2-pentanol polyoxypropylene ether sodium sulfonate.

[0127] Step 3: Synthesis of vinyl acetate-maleate-30 alternating copolymer:

[0128] In a high-pressure reactor equipped with stirring, condensation reflux, temperature control and nitrogen protection, 484.8 mL of diethyl maleate (3 mol), 318.6 mL of vinyl acetate (3 mol), 9 g of AIBN, and 600 mL of toluene were added. The reactor was frozen, vacuumized, and filled with nitrogen three times. The reactor was sealed and the reaction temperature was controlled at 75 °C for 24 h. After the temperature was lowered to room temperature, it was poured into n-hexane for precipitation. After rotary evaporation and separation by suction filtration, CO was introduced into the autoclave. 2 The purge was carried out for 5 h using 12 MPa CO 2 The small molecules that are not volatile are taken out and then dried in vacuum at 40 °C to constant weight.

[0129] Step 4: Preparation of hydrocarbon carbon dioxide gas-soluble foaming agent composition:

[0130] According to the mass percentage in Table 4, the above-mentioned 3,4,4-trimethyl-3-pentanol polyoxyethylene ether and 2,4,4-trimethyl-2-pentanol polyoxypropylene ether sulfonate were mixed and added to 99.1 g of distilled water, and stirred continuously for 45 minutes using a magnetic stirrer. Then, vinyl acetate-maleate-30 alternating copolymer was added, and the mixture was oscillated for 1.5 hours using an ultrasonic oscillator to obtain a hydrocarbon carbon dioxide gas-soluble foaming agent composition.

[0131] Table 4 Composition of hydrocarbon carbon dioxide gas-soluble foaming agent composition

[0132] composition substance Mass percentage Aerosol main agent 3,4,4-Trimethyl-3-pentanol polyoxyethylene ether 0.35% Aerosol accelerator Sodium 2,4,4-trimethyl-2-pentanol polyoxypropylene ether sulfonate 0.25% Aerosol stabilizer Vinyl acetate-maleate-30 alternating copolymer 0.30% water Distilled water margin

[0133] Example 5

[0134] This embodiment uses 3,5,5-trimethyl-1-hexanol polyoxyethylene ether as the gas-soluble main agent, 3-(tert-butyl)-2,2,4,4,-tetramethylpentan-3-ol polyoxypropylene ether sulfonate as the gas-soluble promoter, and vinyl acetate-maleate-30 alternating copolymer as the gas-soluble stabilizer, wherein:

[0135] The molecular structure of 3,5,5-trimethyl-1-hexanol polyoxyethylene ether is:

[0136] ;

[0137] The molecular structure of 3-(tert-butyl)-2,2,4,4,-tetramethylpentan-3-ol polyoxypropylene ether sulfonate is:

[0138] ;

[0139] The molecular structure of vinyl acetate-maleate-30 alternating copolymer is:

[0140] .

[0141] The preparation method of the hydrocarbon carbon dioxide gas-soluble foaming agent composition of this embodiment is:

[0142] Step 1, preparation of 3,5,5-trimethyl-1-hexanol polyoxyethylene ether:

[0143] In a high-pressure stainless steel reactor equipped with a stirring, heating and cooling system, 1.0 mol (144 g) of 3,5,5-trimethyl-1-hexanol and 7.9 g of barium hydroxide catalyst were added, and high-purity nitrogen (purity greater than 99.999%) was purged for 13 minutes, and then 9 mol (396 g) of ethylene oxide was introduced, and the reaction temperature was controlled at 130 ° C for 6.5 hours to obtain a crude product of 3,5,5-trimethyl-1-hexanol polyoxyethylene ether, and the temperature was lowered to discharge the material. The crude product of 3,5,5-trimethyl-1-hexanol polyoxyethylene ether was neutralized with glacial acetic acid, vacuum filtered, dissolved and filtered in ethyl acetate, rotary evaporated and vacuum dried to obtain 3,5,5-trimethyl-1-hexanol polyoxyethylene ether.

[0144] Step 2: Synthesis of 3-(tert-butyl)-2,2,4,4-tetramethylpentan-3-ol polyoxypropylene ether sulfonate:

[0145] In a high-pressure stainless steel reactor equipped with a stirring, heating and cooling system, 1.0 mol (200 g) of 3-(tert-butyl)-2,2,4,4,-tetramethylpentan-3-ol and 14.6 g of magnesium hydroxide catalyst were added, and 13 mol (754 g) of propylene oxide was introduced after purging with high-purity nitrogen for 13 minutes. The reaction temperature was controlled at 130°C for 6.5 hours to obtain a crude product of 3-(tert-butyl)-2,2,4,4,-tetramethylpentan-3-ol polyoxypropylene ether, and the temperature was lowered to discharge the material. The crude product of 3-(tert-butyl)-2,2,4,4,-tetramethylpentan-3-ol polyoxypropylene ether was neutralized with glacial acetic acid, vacuum filtered, dissolved and filtered with ethyl acetate, rotary evaporated and vacuum dried to obtain 3-(tert-butyl)-2,2,4,4,-tetramethylpentan-3-ol polyoxypropylene ether.

[0146] With 60 mL of water as solvent and 40 mL of ethanol as cosolvent, add 3-(tert-butyl)-2,2,4,4,-tetramethylpentan-3-ol polyoxypropylene ether into a three-necked flask, dropwise add a mixed sulfonating agent solution prepared by 10 g of sodium sulfite and 30 g of sodium bisulfite, and stir at 85 ºC for 5 h until the solution becomes one phase to obtain a light yellow liquid. After cooling to room temperature, add isopropanol for extraction, extract the upper extract with dichloromethane, and remove dichloromethane by rotary evaporation to obtain a yellow liquid. The yellow liquid is recrystallized with ethanol 4 times and dried to obtain a white powdery solid 3-(tert-butyl)-2,2,4,4,-tetramethylpentan-3-ol polyoxypropylene ether sodium sulfonate.

[0147] Step 3: Synthesis of vinyl acetate-maleate-30 alternating copolymer:

[0148] In a high-pressure reactor equipped with stirring, condensation reflux, temperature control and nitrogen protection, 484.8 mL of diethyl maleate (3 mol), 318.6 mL of vinyl acetate (3 mol), 9 g of AIBN, and 600 mL of toluene were added. The reactor was frozen, vacuumized, and filled with nitrogen three times. The reactor was sealed and the reaction temperature was controlled to be 60 °C for 12 h. After the temperature was lowered to room temperature, it was poured into n-hexane for precipitation. Most of the liquid after the reaction was rotary evaporated, filtered and separated, and CO was introduced into the autoclave. 2 The purge was carried out for 3.5 h using 15 MPa CO 2 The small molecules that are not volatile are taken out and then dried in vacuum at 40 °C to constant weight.

[0149] Step 4: Preparation of hydrocarbon carbon dioxide gas-soluble foaming agent composition:

[0150] According to the mass percentage in Table 5, the above-mentioned 3,5,5-trimethyl-1-hexanol polyoxyethylene ether and 3-(tert-butyl)-2,2,4,4,-tetramethylpentan-3-ol polyoxypropylene ether sulfonate were mixed and added to 99.1 g of deionized water, and stirred continuously for 45 min using a magnetic stirrer. Then, vinyl acetate-maleate-30 alternating copolymer was added, and the mixture was oscillated for 1.5 h using an ultrasonic oscillator to obtain a hydrocarbon carbon dioxide gas-soluble foaming agent composition.

[0151] Table 5 Composition of hydrocarbon carbon dioxide gas-soluble foaming agent composition

[0152] composition substance Mass percentage Aerosol main agent 3,5,5-Trimethyl-1-hexanol polyoxyethylene ether 0.25% Aerosol accelerator Sodium 3-(tert-butyl)-2,2,4,4-tetramethylpentan-3-ol polyoxypropylene ether sulfonate 0.20% Aerosol stabilizer Vinyl acetate-maleate-30 alternating copolymer 0.45% water Deionized water margin

[0153] Comparative Example 1

[0154] Same as Example 1, except that no aerosol accelerator was used.

[0155] Comparative Example 2

[0156] Same as Example 1, except that no gas-soluble stabilizer is used.

[0157] Comparative Example 3

[0158] This comparative example uses the aerosol surfactant fatty alcohol polyoxyethylene polyoxypropylene ether disclosed in patent CN103867169A to replace the hydrocarbon carbon dioxide aerosol foaming agent composition as the aerosol foaming agent.

[0159] The molecular structural formula of the fatty alcohol polyoxyethylene polyoxypropylene ether is:

[0160] ,

[0161] Where n is 5 and m is 9.

[0162] Comparative Example 4

[0163] The same as Example 1, except that the aerosol main agent is replaced by the aerosol surfactant fatty alcohol polyoxyethylene polyoxypropylene ether disclosed in CN103867169A, and the molecular structure of the fatty alcohol polyoxyethylene polyoxypropylene ether is:

[0164] ,

[0165] Where n is 5 and m is 9.

[0166] Comparative Example 5

[0167] Same as Example 1, except that the aerosol accelerator is replaced by triethanolamine.

[0168] Comparative Example 6

[0169] Same as Example 1, except that the aerosol stabilizer is replaced by carboxymethyl cellulose.

[0170] For the CO in Examples 1 to 5 and Comparative Examples 1 to 6 2 The gas-soluble foaming agent compositions were evaluated in CO 2 The solubility and foam performance of the solution were determined by the turbidity method and the foam performance was determined by the Waring-Blender method. The solubility results are shown in Table 6 and the foam performance results are shown in Table 7.

[0171] Table 6 Solubility of blowing agent in supercritical carbon dioxide at 60℃

[0172] project Cloud point pressure (MPa) Dissolved mass fraction (%) Example 1 15.61 0.3 Example 2 15.60 0.3 Example 3 15.66 0.3 Example 4 15.20 0.3 Example 5 15.46 0.3 Comparative Example 1 14.36 0.3 Comparative Example 2 16.39 0.3 Comparative Example 3 19.90 0.3 Comparative Example 4 17.35 0.3 Comparative Example 5 18.55 0.3 Comparative Example 6 18.96 0.3

[0173] As shown in Table 6, without the aid of low-carbon alcohol cosolvent, the carbon dioxide gas-soluble foaming agent composition of the present invention can achieve a higher supercritical carbon dioxide solubility performance. This is because the single agent constituting the composition introduces a CO2-philic 2 This is due to the increased free volume of the groups (polyoxyethylene group, polyoxypropylene group, polyvinyl acetate group, polydiethyl maleate group) and the polymethyl groups.

[0174] Table 7 Foam properties of foaming agent at mass fraction 0.3%

[0175] project Dialysis half-life (min) Foaming volume (mL) Foam comprehensive value (mL·min) Example 1 32.04 321 10284.84 Example 2 33.71 330 11124.30 Example 3 31.35 305 9561.75 Example 4 33.12 324 10730.88 Example 5 33.25 341 11338.25 Comparative Example 1 27.18 239 6496.02 Comparative Example 2 14.36 420 6031.20 Comparative Example 3 5.14 537 2400.38 Comparative Example 4 12.56 270 3391.20 Comparative Example 5 7.01 222 1556.22 Comparative Example 6 9.11 247 2250.17

[0176] In Comparative Examples 1 and 2, no gas-soluble promoter or gas-soluble stabilizer was used. Although their solubility was almost the same as that of Examples 1-5, their foaming performance was poor. Comparative Example 3 directly used fatty alcohol polyoxyethylene polyoxypropylene ether as the gas-soluble foaming agent. Without adding low-carbon alcohol cosolvent, the solubility was extremely poor.

[0177] The replacement of the gas-soluble main agent, gas-soluble promoter or gas-soluble stabilizer in Comparative Examples 4-6 leads to a decrease in the solubility of supercritical carbon dioxide, mainly because the compatibility of the substitute substances used with supercritical carbon dioxide is poor. Specifically: Comparative Example 4 replaces the gas-soluble main agent with fatty alcohol polyoxyethylene polyoxypropylene ether, and the molecular structure of this substitute does not match the polarity and diffusivity of carbon dioxide, resulting in a decrease in its solubility in supercritical carbon dioxide; Comparative Example 5 replaces the gas-soluble promoter with triethanolamine. Although triethanolamine has a certain polarity, its solubility and interfacial activity are poor, and it is difficult to effectively disperse in supercritical carbon dioxide, so its solubility is low; Comparative Example 6 replaces the gas-soluble stabilizer with carboxymethyl cellulose, which is a water-soluble polymer with a high molecular weight and strong hydrophilicity, making it poorly soluble in non-polar or supercritical carbon dioxide.

[0178] As can be seen from Table 7, the hydrocarbon carbon dioxide gas-soluble foaming agent compositions of Examples 1 to 5 have relatively high foaming ability and foam stability, which is because the gas-soluble promoter improves the foaming ability and the gas-soluble stabilizer improves the foam stabilizing ability.

[0179] In Comparative Example 1, no aerosol accelerator is used, and the foaming ability is lower than that of Examples 1 to 5, which shows that in the absence of an aerosol accelerator, the foaming ability of the foam system is weak. The aerosol accelerator (polymethyl alcohol polyoxypropylene ether sulfonate) itself, as an anionic surfactant, can form a compound system with a nonionic aerosol main agent (polymethyl alcohol polyoxyethylene ether) to jointly reduce the interfacial tension and enhance the strength of the liquid film. This anionic-non-compounding can significantly reduce the interfacial tension and improve the foaming efficiency. If the aerosol accelerator is lacking, the arrangement density of the single aerosol main agent molecule on the interface is low, resulting in poor liquid film strength and adhesion, thereby affecting the formation of bubbles. Therefore, in the absence of an accelerator, the foaming ability of Comparative Example 1 is greatly reduced.

[0180] Comparative Example 2 does not use an aerosol stabilizer, and its foam comprehensive value is significantly lower than that of Examples 1 to 5, indicating that its foam stability is poor. The aerosol stabilizer (vinyl acetate-maleate alternating copolymer) can form a three-dimensional network structure in the liquid film, thereby enhancing the viscoelasticity of the liquid film, improving the shear resistance of the liquid film, and delaying the drainage process and rupture speed of the foam. In the absence of a stabilizer, the liquid film lacks an interwoven molecular structure, resulting in easy loss of liquid and easy merging and rupture of bubbles. Therefore, the foam stabilization performance of Comparative Example 2 is significantly reduced, which is manifested as a significant reduction in the foam comprehensive value.

[0181] Comparative Example 3 replaces the aerosol main agent with fatty alcohol polyoxyethylene polyoxypropylene ether, and its foaming property is enhanced but the foam stability is deteriorated. Reasons for improved foaming performance: fatty alcohol polyoxyethylene polyoxypropylene ether has a lower critical micelle concentration (CMC), which can form foam on the interface faster, so it shows a higher foaming volume in the initial stage. Reasons for reduced foam stability: fatty alcohol polyoxyethylene polyoxypropylene ether is a short-chain molecule with weak intermolecular forces and insufficient viscoelasticity in the liquid film, which makes the foam liquid film easy to drain and merge. At the same time, it lacks the long-chain flexibility and highly methylated structure at the tail end like polymethyl alcohol polyoxyethylene ether, and it is difficult to form a stable three-dimensional network structure with aerosol promoters and stabilizers. In this way, the liquid film is easy to break and the foam stability is reduced. Therefore, although the foaming ability is enhanced, the foam is easy to break and disappear, resulting in a lower comprehensive foam value than the embodiment.

[0182] The foam performance of Comparative Examples 4-6 is poor, mainly because the replaced reagents cannot form an effective synergistic effect, resulting in a decrease in interface stability and the integrity of the foam structure: in Comparative Example 4, the gas-soluble main agent is replaced by fatty alcohol polyoxyethylene polyoxypropylene ether, whose interfacial activity and structural tightness are not as good as polymethyl alcohol polyoxyethylene ether, so its synergistic effect with the gas-soluble promoter is insufficient, resulting in an unstable foam film; in Comparative Example 5, the gas-soluble promoter is replaced by triethanolamine, which lacks a suitable molecular structure to quickly adsorb to the gas-liquid interface and form a tight composite interface with the gas-soluble main agent, resulting in a decrease in foam formation efficiency and stability; in Comparative Example 6, after replacing vinyl acetate-maleate alternating copolymer with carboxymethyl cellulose, it lacks the ability to form a three-dimensional network structure and cannot increase the viscoelasticity of the liquid film. The foam liquid film is more likely to rupture, resulting in poor shear resistance and rupture resistance of the foam.

[0183] Effect verification example 1

[0184] During the foam formation process, the microscopic morphology of the foam was observed using a Keyence microscope. The microscopic morphologies of the foam liquid films of Example 1 and Comparative Example 3 are shown in Figures 1 and 2. Figure 1 and Figure 2 As shown. By comparing the two, it can be found that the carbon dioxide gas-soluble foam formed by the present invention is significantly higher than that of comparative example 3 in terms of liquid film thickness and base liquid viscosity. This is due to the addition of gas-soluble promoters and gas-soluble stabilizers. A part of them adheres to the liquid film, which can significantly reduce the interfacial tension of the foam system, making the foam liquid film more uniform and having higher adhesion, and the other part is interwoven and entangled in the foam liquid film to form a three-dimensional network structure, thereby increasing the viscosity of the liquid film and the viscoelasticity of the foam liquid film, thereby limiting the loss of liquid, slowing down the drainage process of bubbles, prolonging the survival time of the foam, and improving the shear resistance of the foam, making the foam more stable under dynamic conditions.

[0185] Any equivalent structure or equivalent process transformation based on the present invention, or directly or indirectly applied to other related technical fields, is included in the patent protection scope of the present invention. The embodiments of the present invention are only examples and do not limit the patent scope of the present invention.

Claims

1. A hydrocarbon carbon dioxide gas-soluble foaming agent composition, characterized in that: include: Aerosol main agent, aerosol accelerator, aerosol stabilizer, water; The gas-soluble main agent is polymethyl alcohol polyoxyethylene ether, and the general molecular structure formula is: ， wherein R is any one of 3,5,5-trimethyl-1-hexyl, 2,3-dimethyl-2-heptyl, 2,4,4-trimethyl-1-pentyl, 2,2,4-trimethyl-3-pentyl, 3,4,5-trimethyl-4-heptyl, 3,4,4-trimethyl-3-pentyl, 2,3,4-trimethyl-3-pentyl, 2,3,3-trimethyl-2-pentyl, 2,4,6-trimethyl-4-heptyl, 2,4,4-trimethyl-2-pentyl, 2,6,6-trimethyl-4-heptynyl, 3,4,4-trimethyl-1-pentynyl, 3,4,4-trimethyl-1-pentenyl, 3-(tert-butyl)-2,2,4,4,-tetramethylpentyl, 2,3,3-trimethyl-2-butyl, and 3-methyl-2-butyl; The value range of m is 5~15; The aerosol accelerator is polymethyl alcohol polyoxypropylene ether sulfonate, and the general molecular structure is as follows: ， wherein R′ is any one of 3,5,5-trimethyl-1-hexyl, 2,3-dimethyl-2-heptyl, 2,4,4-trimethyl-1-pentyl, 2,2,4-trimethyl-3-pentyl, 3,4,5-trimethyl-4-heptyl, 3,4,4-trimethyl-3-pentyl, 2,3,4-trimethyl-3-pentyl, 2,3,3-trimethyl-2-pentyl, 2,4,6-trimethyl-4-heptyl, 2,4,4-trimethyl-2-pentyl, 2,6,6-trimethyl-4-heptynyl, 3,4,4-trimethyl-1-pentynyl, 3,4,4-trimethyl-1-pentenyl, 3-(tert-butyl)-2,2,4,4,-tetramethylpentyl, 2,3,3-trimethyl-2-butyl, and 3-methyl-2-butyl; The value range of n is 10~25; The gas-soluble stabilizer is a vinyl acetate-maleate alternating copolymer, and the general molecular structure formula is as follows: ， The value range of y is 30~50; The content of each component is as follows by mass percentage: The gas-soluble main agent is 0.2~0.5%, the gas-soluble promoter is 0.1~0.3%, the gas-soluble stabilizer is 0.3~1.0%, and the balance is water.

2. A method for preparing a hydrocarbon carbon dioxide gas-soluble foaming agent composition, characterized in that ， The hydrocarbon carbon dioxide gas-soluble foaming agent composition as claimed in claim 1, wherein the preparation method comprises the following steps: Step 1, synthesis of polymethyl alcohol polyoxyethylene ether: In a reaction kettle, polymethyl alcohol and an alkaline catalyst are added, ethylene oxide is introduced after nitrogen purging for 10 to 15 minutes, and the introduction time is 1 to 10 hours. The reaction temperature is controlled at 120 to 130°C for 1 to 10 hours. After the reaction is completed, the temperature is lowered and the material is discharged to obtain a crude product of polymethyl alcohol polyoxyethylene ether; the crude product of polymethyl alcohol polyoxyethylene ether is neutralized by adding glacial acetic acid, washed with water, and evaporated in vacuum to obtain polymethyl alcohol polyoxyethylene ether; Step 2: Synthesis of polymethyl alcohol polyoxypropylene ether sulfonate: In a reaction kettle, polymethyl alcohol and an alkaline catalyst are added, propylene oxide is introduced after nitrogen purging for 10 to 15 minutes, and the introduction time is 1 to 10 hours. The reaction temperature is controlled at 120 to 130 ° C for 1 to 10 hours. After the reaction is completed, the temperature is lowered and the material is discharged to obtain a crude product of polymethyl alcohol polyoxypropylene ether; the crude product of polymethyl alcohol polyoxypropylene ether is neutralized by adding glacial acetic acid, washed with water, and evaporated in vacuum to obtain polymethyl alcohol polyoxypropylene ether; Using water as solvent and ethanol as co-solvent, adding polymethyl alcohol polyoxypropylene ether, then dropping a mixed sulfonating agent solution prepared by sodium sulfite and sodium bisulfite, stirring and reacting at 80-100°C for 4-8 hours until the solution becomes one phase; after cooling to room temperature, extracting, rotary evaporating, and recrystallizing to obtain polymethyl alcohol polyoxypropylene ether sulfonate; Step 3: Synthesis of vinyl acetate-maleate alternating copolymer: In a reactor, vinyl acetate and diethyl maleate are added in a molar ratio of 1:1, and toluene solvent is added. After the mixture is completely dissolved, AIBN is added. Under nitrogen protection, the reactor is sealed, heated to 60-80°C, and stirred for 12-24 hours. After the temperature of the reactor is lowered to room temperature, n-hexane is poured into the reactor for precipitation. After rotary evaporation and suction filtration, the mixture is placed in a high-pressure reactor, and CO2 is introduced for purging and replacement for 3-6 hours, followed by drying to obtain a vinyl acetate-maleate alternating copolymer. Step 4: Preparation of hydrocarbon carbon dioxide gas-soluble foaming agent composition: The polymethyl alcohol polyoxyethylene ether and the polymethyl alcohol polyoxypropylene ether sulfonate are mixed and stirred for 20 to 60 minutes, and then the vinyl acetate-maleate alternating copolymer is added and shaken for 1 to 2 hours to obtain a hydrocarbon carbon dioxide gas-soluble foaming agent composition.

3. The method for preparing the hydrocarbon carbon dioxide gas-soluble foaming agent composition according to claim 2, characterized in that: The polymethyl alcohols in step 1 and step 2 are 3,5,5-trimethyl-1-hexanol, 2,3-dimethyl-2-heptanol, 2,4,4-trimethyl-1-pentanol, 2,2,4-trimethyl-3-pentanol, 3,4,5-trimethyl-4-heptanol, 3,4,4-trimethyl-3-pentanol, 2,3,4-trimethyl-3-pentanol, 2,3,3-trimethyl-2-pentanol, 2,4 ,6-trimethyl-4-heptanol, 2,4,4-trimethyl-2-pentanol, 2,6,6-trimethyl-4-heptyn-3-ol, 3,4,4-trimethyl-1-pentyn-3-ol, 3,4,4-trimethyl-1-penten-3-ol, 3-(tert-butyl)-2,2,4,4,-tetramethylpentan-3-ol, 2,3,3-trimethyl-2-butanol, and 3-methyl-2-butanol.

4. The method for preparing the hydrocarbon carbon dioxide gas-soluble foaming agent composition according to claim 2, characterized in that: In step 1, the molar ratio of the polymethyl alcohol to ethylene oxide is 1:(5-15); In step 2, the molar ratio of the polymethyl alcohol to propylene oxide is 1:(10-25).

5. The method for preparing the hydrocarbon carbon dioxide gas-soluble foaming agent composition according to claim 2, characterized in that: The alkaline catalyst is a mixture of one or more of calcium hydroxide, barium hydroxide and magnesium hydroxide.

6. The method for preparing the hydrocarbon carbon dioxide gas-soluble foaming agent composition according to claim 2, characterized in that: In step 1, the added mass of the alkaline catalyst is 1.0-2.5% of the total mass of the polymethyl alcohol and ethylene oxide; In step 2, the added mass of the alkaline catalyst is 0.5-2.0% of the total mass of the polymethyl alcohol and propylene oxide.

7. The method for preparing the hydrocarbon carbon dioxide gas-soluble foaming agent composition according to claim 2, characterized in that: In step 2, the molar ratio of the mixed sulfonating agent solution to the polymethyl alcohol polyoxypropylene ether is 1: (1-5); The molar ratio of the sodium sulfite to the sodium bisulfite is 1:(1-5).

8. The method for preparing the hydrocarbon carbon dioxide gas-soluble foaming agent composition according to claim 2, characterized in that: In step 3, the volume of the toluene solvent is 70-90% of the total volume of vinyl acetate and diethyl maleate.

9. The method for preparing the hydrocarbon carbon dioxide gas-soluble foaming agent composition according to claim 2, characterized in that: In step 3, the mass of AIBN is 1-3% of the total mass of vinyl acetate and diethyl maleate.

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