A modified vegetable oil-based aqueous mold release agent and its preparation method

Abstract

The present invention relates to the technical field of mold release agents, and discloses a modified vegetable oil-based waterborne mold release agent and a preparation method thereof. By mass ratio, it includes modified self-emulsifying epoxy soybean oil, a curing agent, and deionized water with a dosage ratio of 100:2.55 to 7.36:0.24 to 1.2; the preparation method of the modified self-emulsifying epoxy soybean oil includes the following steps: mixing epoxy soybean oil and a modifier in a molar ratio of 1 to 2:1, heating to 100 to 200 °C, and reacting for 2 to 4 h to obtain material A; the modifier molecule contains a nonionic group and an anionic group; the curing agent molecule contains an amino group. In the modified vegetable oil-based waterborne mold release agent of the present invention, through high-temperature chemical modification treatment of the modifier and epoxy soybean oil, the molecular structure and functional groups contained in the epoxy soybean oil are optimized, and an active group is introduced through the curing agent, so that the finally prepared mold release agent has stronger water resistance and mold release performance, and the applicable scenarios are more extensive.

Description

Technical Field

[0001] The present invention relates to the technical field of mold release agents, and more particularly to a modified vegetable oil-based aqueous mold release agent and a preparation method thereof. Background Art

[0002] A mold release agent is a functional substance between the mold and the finished product, used to assist the finished product to separate from the mold. In the construction field, the mold release agent for concrete refers to a substance applied to the construction formwork before concrete pouring, which can make the formwork after pouring adhere to the concrete surface as little as possible, so that the concrete surface is smooth and flat. For the above-mentioned mold release agent for concrete, it can be roughly divided into an oil-based mold release agent and an aqueous mold release agent according to the affinity for water. In the actual application process, the oil-based mold release agent is easy to pollute the concrete surface, resulting in many holes on the concrete surface and a large consumption per unit area. Now it has been gradually replaced by the aqueous mold release agent.

[0003] Most aqueous mold release agents are mainly composed of mineral oil, plus appropriate emulsifiers and other auxiliaries, and are obtained after high-speed stirring and emulsifying dispersion. However, in the currently common aqueous mold release agents, after long-term storage, phenomena such as stratification are likely to occur, affecting their normal use; and after the aqueous mold release agent dries and forms a film on the mold surface, the formed film is not water-resistant. In rainy or humid environments, the formed film is easily washed away by rain or water vapor, resulting in a decrease in the mold release effect, so that the aqueous mold release agent is difficult to be promoted and used in many regions and scenarios.

[0004] In addition, mineral oil is a non-renewable resource. The large-scale use of petrochemical materials such as mineral oil is not conducive to environmental protection and sustainable development; and because the HLB values of different mineral oils are different, it is necessary to detect each batch of mineral oil before each production to obtain the HLB value, so as to determine its relevant properties, resulting in a large workload and low production efficiency.

[0005] For this reason, an aqueous mold release agent using vegetable oil as the base material has been proposed and improved. For example, the patent with the publication number CN114164039A provides an environmentally friendly concrete mold release agent and a preparation method thereof, including vegetable oil, an oil-soluble emulsifier, a water-soluble emulsifier, a penetrant, and an antifoaming component, etc. By mixing various emulsifiers into the vegetable oil, its emulsification effect is improved, and through the penetrant and the antifoaming component, the holes formed in the concrete are filled, etc. However, although the above-mentioned mold release agent can keep the emulsion in a super-stable state, its water resistance is poor and its applicability is low in many actual application scenarios.

[0006] Based on this, there is an urgent need for an aqueous mold release agent for concrete with better water resistance on the basis of maintaining good stability and emulsification effect. Summary of the Invention

[0007] Technical problems to be solved by the present invention:

[0008] Currently, in the production and processing of concrete workpieces, common water-based mold release agents are extremely prone to phenomena such as delamination after long-term storage, affecting their normal use; and after the water-based mold release agent dries into a film, the water resistance of the film is poor, and it is easily washed away in rainy or humid environments, thus affecting the mold release work, that is, the requirements for the application environment conditions are relatively high.

[0009] Technical solutions adopted by the present invention:

[0010] The present invention provides a modified vegetable oil-based water-based mold release agent, which includes modified self-emulsifying epoxy soybean oil, a curing agent, and deionized water;

[0011] The preparation method of the modified self-emulsifying epoxy soybean oil includes the following steps:

[0012] Mix epoxy soybean oil with a modifier, heat to 100 - 200 °C, and react for 2 - 4 h to obtain the modified self-emulsifying epoxy soybean oil;

[0013] The modifier molecule contains a non-ionic group and an anionic group; the curing agent molecule contains an amino group.

[0014] Preferably, in the modifier molecule, the non-ionic group is a polyethylene glycol group, and the anionic group is a sulfonate group.

[0015] Preferably, the preparation method of the modifier includes the following steps:

[0016] Mix a high molecular raw material I containing a polyethylene glycol group with a raw material II containing a sulfonate group, and prepare the modifier through an addition reaction.

[0017] Preferably, the high molecular raw material I is selected from one or more of polyethylene glycol acrylate, isobutenyl polyethylene glycol, and allyl polyoxyethylene ether.

[0018] Preferably, the raw material II is one or more of sodium sulfite and sodium bisulfite.

[0019] Preferably, in the addition reaction, the temperature is controlled at 30 - 80 °C, and the reaction time is 60 - 90 min.

[0020] Preferably, in the preparation process of the modified self-emulsifying epoxy soybean oil, the mass ratio of epoxy soybean oil to the modifier is 1 - 2:1.

[0021] Preferably, the curing agent includes one or more of diethylenetriamine, triethylenetetramine, 1,6-hexanediamine, and polyetheramine.

[0022] The preparation method of the modified vegetable oil-based waterborne mold release agent as described above includes the following steps:

[0023] Mix the modified self-emulsifying epoxy soybean oil, curing agent and deionized water, and stir well to obtain the modified vegetable oil-based waterborne mold release agent.

[0024] Preferably, the mass ratio of the modified self-emulsifying epoxy soybean oil, curing agent and deionized water is 100:2.55 - 7.36:0.24 - 1.2.

[0025] Advantages of the present invention are manifested in:

[0026] It is found through research in the present invention that the existing waterborne mold release agents have the problem of poor water resistance, mostly due to the use of externally added emulsifiers. Since the emulsion system is a thermodynamically unstable system, a large amount of emulsifiers in the mold release agent are prone to problems such as falling off when encountering water after film formation.

[0027] Based on this, in the present invention, through modification treatment, the self-emulsification of epoxy soybean oil is realized. And during the modification process, through high-temperature chemical modification, the functional groups and molecular structure of epoxy soybean oil are optimized, and activation groups are introduced through the curing agent, so that the finally prepared mold release agent has stronger water resistance and mold release performance, and has a wider range of application scenarios.

[0028] Specifically, the modifier used in the present invention is a multifunctional functional group modifier obtained by an addition reaction of a high-molecular organic compound containing a polyethylene glycol group and an anionic salt containing a sulfonate group. When the modifier modifies epoxy soybean oil, the polyethylene glycol group and sulfonate group can be introduced into epoxy soybean oil through hydroxyl groups to thoroughly and effectively improve the stability of the emulsion.

[0029] Furthermore, in the present invention, environmentally friendly epoxy soybean oil is used as the base raw material, and the modified self-emulsifying epoxy soybean oil system obtained through modification contains an excessive amount of epoxy groups, while the curing agent contains a large number of active groups. Therefore, when the modified self-emulsifying epoxy soybean oil combines with the curing agent, cross-linking reactions will occur between the epoxy groups and the active groups, making the mold release agent system have a high degree of cross-linking, thereby effectively improving the water resistance of the mold release agent. Specific Embodiments

[0030] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Those not specified in the embodiments are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or instruments not specified in the manufacturer are all conventional products that can be obtained through commercial purchase.

[0031] The present invention provides a modified vegetable oil-based waterborne mold release agent, which includes material A and material B with a mass ratio of 100:3 - 8:

[0032] (1) Component A is modified self-emulsifying epoxy soybean oil:

[0033] React epoxy soybean oil with a modifier. The hydroxyl groups in the modifier can modify the molecular structure of epoxy soybean oil, introducing non-ionic groups and anionic groups, namely polyethylene glycol groups and sulfonate groups, into the epoxy soybean oil molecules, thereby thoroughly improving the stability of the emulsion, achieving the self-emulsifying method, and during production preparation, there is no need to measure the HLB value of the crude oil, which can reduce the workload and improve production efficiency.

[0034] Specifically, the preparation method of Component A includes the following steps:

[0035] A1 Prepare the modifier: Take a high-molecular organic compound containing double bonds and sodium sulfite and / or sodium bisulfite in a molar ratio of 1:1 to 1.1, mix them, and carry out an addition reaction at 30 - 80 °C for 60 - 90 min;

[0036] The high-molecular organic compound is selected from one or more of polyethylene glycol acrylate, isobutenyl polyethylene glycol (VPEG), and allyl polyoxyethylene ether (HPEG). Each of them contains a double bond and a hydroxyl group in its molecule. Those skilled in the art can select other high-molecular organic compounds containing double bonds, hydroxyl groups, and polyethylene glycol groups with the same effect according to the actual situation.

[0037] In this process, functional groups with improved stability are introduced into the modifier system through the addition reaction, facilitating the subsequent modification treatment of epoxy soybean oil.

[0038] A2 Prepare Component A: Take epoxy soybean oil and the modifier in a molar ratio of 1 - 2:1, mix them, heat to 100 - 200 °C for reaction for 2 - 4 h to obtain modified self-emulsifying epoxy soybean oil; in a high-temperature environment, the modifier can chemically modify epoxy soybean oil, introduce functional groups, improve the emulsification performance of epoxy soybean oil, and achieve the self-emulsifying effect.

[0039] (2) Component B is an aqueous solution of a curing agent:

[0040] During the process of mixing Component A and Component B, the modified self-emulsifying epoxy soybean oil contains a large amount of epoxy groups, which can cross-link with the active groups, namely amino groups, in the aqueous solution of the curing agent, improving the cross-linking degree of the film and enhancing the water resistance of the release agent.

[0041] Specifically, the aqueous solution of the curing agent is prepared by mixing one or more mixtures of diethylenetriamine, triethylenetetramine, 1,6 - hexanediamine, and polyetheramine with deionized water. Among them, the mass fraction of deionized water is 8 - 15%.

[0042] In the present invention, the epoxy soybean oil contains epoxy linoleate, epoxy oleate and epoxy palmitate. Preferably, the epoxy soybean oil with an epoxy value of 6-7% and a viscosity of 320-330 mPa·s at 25°C is used.

[0043] <Example>

[0044] Example 1

[0045] (1) Preparation of modifier:

[0046] Take polyethylene glycol acrylate and sodium sulfite according to a molar ratio of 1:1.05, mix them, and place them at a temperature of about 55°C for 75 minutes to obtain the modifier.

[0047] (2) Preparation of modified self-emulsifying epoxy soybean oil:

[0048] Take epoxy soybean oil and the modifier according to a molar ratio of 1.5:1, mix them, and place them under high-temperature conditions of about 150°C for 3 hours to obtain the modified self-emulsifying epoxy soybean oil.

[0049] (3) Preparation of curing agent aqueous solution:

[0050] Take diethylenetriamine, add deionized water, and control the deionized water to account for 10% of the total mass of the solution, stir well to dissolve, and obtain the curing agent aqueous solution.

[0051] (4) Preparation of modified vegetable oil-based waterborne release agent:

[0052] Take the modified self-emulsifying epoxy soybean oil and the curing agent aqueous solution according to a mass ratio of 100:5, mix them evenly to obtain the modified vegetable oil-based waterborne release agent.

[0053] Example 2

[0054] (1) Preparation of modifier:

[0055] Take isobutenyl polyethylene glycol and sodium sulfite according to a molar ratio of 1:1.05, mix them, and place them at a temperature of about 55°C for 75 minutes to obtain the modifier.

[0056] (2) Preparation of modified self-emulsifying epoxy soybean oil:

[0057] Take epoxy soybean oil and the modifier according to a molar ratio of 1.5:1, mix them, and place them under high-temperature conditions of about 150°C for 3 hours to obtain the modified self-emulsifying epoxy soybean oil.

[0058] (3) Preparation of curing agent aqueous solution:

[0059] Take diethylenetriamine, add deionized water, control the deionized water to account for 10% of the total mass of the solution, stir well to dissolve, and obtain an aqueous solution of the curing agent;

[0060] (4) Prepare a modified vegetable oil-based waterborne mold release agent:

[0061] Take the modified self-emulsifying epoxy soybean oil and the aqueous solution of the curing agent in a mass ratio of 100:5, mix them evenly to obtain a modified vegetable oil-based waterborne mold release agent.

[0062] Example 3

[0063] (1) Prepare a modifier:

[0064] Take allyl polyoxyethylene ether and sodium sulfite in a molar ratio of 1:1.05, mix them, place them at a temperature of about 55 °C, and react for 75 min to obtain a modifier;

[0065] (2) Prepare a modified self-emulsifying epoxy soybean oil:

[0066] Take epoxy soybean oil and the modifier in a molar ratio of 1.5:1, mix them, place them under high temperature conditions of about 150 °C, and react for 3 h to obtain a modified self-emulsifying epoxy soybean oil;

[0067] (3) Prepare an aqueous solution of the curing agent:

[0068] Take diethylenetriamine, add deionized water, control the deionized water to account for 10% of the total mass of the solution, stir well to dissolve, and obtain an aqueous solution of the curing agent;

[0069] (4) Prepare a modified vegetable oil-based waterborne mold release agent:

[0070] Take the modified self-emulsifying epoxy soybean oil and the aqueous solution of the curing agent in a mass ratio of 100:5, mix them evenly to obtain a modified vegetable oil-based waterborne mold release agent.

[0071] Example 4

[0072] (1) Prepare a modifier:

[0073] Take polyethylene glycol acrylate and sodium sulfite in a molar ratio of 1:1.05, mix them, place them at a temperature of about 55 °C, and react for 75 min to obtain a modifier;

[0074] (2) Prepare a modified self-emulsifying epoxy soybean oil:

[0075] Take epoxy soybean oil and the modifier in a molar ratio of 1.5:1, mix them, place them under high temperature conditions of about 150 °C, and react for 3 h to obtain a modified self-emulsifying epoxy soybean oil;

[0076] (3) Prepare an aqueous solution of the curing agent:

[0077] Take triethylenetetramine, add deionized water, control the deionized water to account for 10% of the total mass of the solution, stir well to dissolve, and obtain an aqueous solution of the curing agent;

[0078] (4) Prepare a modified vegetable oil-based waterborne mold release agent:

[0079] Take the modified self-emulsifying epoxy soybean oil and the aqueous solution of the curing agent in a mass ratio of 100:5, mix them evenly to obtain a modified vegetable oil-based waterborne mold release agent.

[0080] Example 5

[0081] (1) Prepare a modifier:

[0082] Take polyethylene glycol acrylate and sodium sulfite in a molar ratio of 1:1.05, mix them, place them at a temperature of about 55 °C, and react for 75 min to obtain a modifier;

[0083] (2) Prepare a modified self-emulsifying epoxy soybean oil:

[0084] Take epoxy soybean oil and the modifier in a molar ratio of 1.5:1, mix them, place them under high-temperature conditions of about 150 °C, and react for 3 h to obtain a modified self-emulsifying epoxy soybean oil;

[0085] (3) Prepare an aqueous solution of the curing agent:

[0086] Take 1,6-hexanediamine, add deionized water, control the deionized water to account for 10% of the total mass of the solution, stir well to dissolve, and obtain an aqueous solution of the curing agent;

[0087] (4) Prepare a modified vegetable oil-based waterborne mold release agent:

[0088] Take the modified self-emulsifying epoxy soybean oil and the aqueous solution of the curing agent in a mass ratio of 100:5, mix them evenly to obtain a modified vegetable oil-based waterborne mold release agent.

[0089] Example 6

[0090] (1) Prepare a modifier:

[0091] Take polyethylene glycol acrylate and sodium sulfite in a molar ratio of 1:1.05, mix them, place them at a temperature of about 55 °C, and react for 75 min to obtain a modifier;

[0092] (2) Prepare a modified self-emulsifying epoxy soybean oil:

[0093] Take epoxy soybean oil and the modifier in a molar ratio of 1.5:1, mix them, place them under high-temperature conditions of about 150 °C, and react for 3 h to obtain a modified self-emulsifying epoxy soybean oil;

[0094] (3) Prepare an aqueous solution of the curing agent:

[0095] Take polyetheramine, add deionized water, control the deionized water to account for 10% of the total mass of the solution, stir well to dissolve, and obtain an aqueous solution of the curing agent;

[0096] (4) Prepare a modified vegetable oil-based waterborne mold release agent:

[0097] Take the modified self-emulsifying epoxy soybean oil and the aqueous solution of the curing agent in a mass ratio of 100:5, mix well, and obtain a modified vegetable oil-based waterborne mold release agent.

[0098] <Comparative Example>

[0099] Comparative Example 1

[0100] (1) Prepare a modifier:

[0101] Take polyethylene glycol acrylate and sodium sulfite in a molar ratio of 1:1.05, mix them, place them at a temperature of about 55 °C, and react for 75 min to obtain a modifier;

[0102] (2) Prepare a composite epoxy soybean oil:

[0103] Take epoxy soybean oil and the modifier in a molar ratio of 1.5:1, mix them, place them at a temperature of about 60 °C, and react for 3 h to obtain a composite epoxy soybean oil;

[0104] (3) Prepare an aqueous solution of the curing agent:

[0105] Take diethylenetriamine, add deionized water, control the deionized water to account for 10% of the total mass of the solution, stir well to dissolve, and obtain an aqueous solution of the curing agent;

[0106] (4) Prepare a mold release agent:

[0107] Take the composite epoxy soybean oil and the aqueous solution of the curing agent in a mass ratio of 100:5, mix well, and obtain a mold release agent.

[0108] Comparative Example 2

[0109] (1) Prepare an aqueous solution of the curing agent:

[0110] Take diethylenetriamine, add deionized water, control the deionized water to account for 10% of the total mass of the solution, stir well to dissolve, and obtain an aqueous solution of the curing agent;

[0111] (2) Prepare a mold release agent:

[0112] Take epoxy soybean oil and the aqueous solution of the curing agent in a mass ratio of 100:5, mix well, and obtain a mold release agent.

[0113] Comparative Example 3

[0114] (1) Preparation of the curing agent aqueous solution:

[0115] Take diethylenetriamine, add deionized water, control the deionized water to account for 10% of the total mass of the solution, stir evenly to dissolve, and obtain the curing agent aqueous solution;

[0116] (2) Preparation of the release agent:

[0117] According to the mass ratio of 100:65:5, take epoxy soybean oil, soybean oil emulsifier (provided by Jiangsu Haian Petrochemical), and the curing agent aqueous solution, mix evenly, and obtain the release agent.

[0118] <Test Example>

[0119] Samples: Examples 1-6, Comparative Examples 1-3

[0120] Prepare the release agent in the manner of Examples 1-6 and Comparative Examples 1-3, and randomly sample the prepared release agent products to obtain the samples of Examples 1-6 and Comparative Examples 1-3.

[0121] (1) Stability test

[0122] Mix the sampled samples with water according to the mass ratio of 1:9, place them in a test tube, let them stand still, observe their layering situation, record the time when no layering occurs or layering begins, and summarize the results in Table 1 below:

[0123] Table 1 Sample stability test situation

[0124]

[0125]

[0126] Among them, before the formal test, a pre-test is carried out first. The results show that the release agent prepared by Examples 1-6 begins to show layering after nearly 100 days, while the release agent prepared by Comparative Examples 1-3 shows layering within 10 days. Based on this, during the formal test, the samples of Examples 1-6 are tested and recorded every 5 days, while the samples of Comparative Examples 1-3 are recorded every day. Therefore, if the first day of layering is accurately observed, record the time when layering begins; if the first day of layering cannot be accurately judged, record the longest time without layering.

[0127] It can be seen from the stability test situation in Table 1 above that:

[0128] The release agents of Examples 1-6 can always remain without layering for at least 70 days, while the release agents of Comparative Examples 1-3 all show layering within 10 days. That is, the release agents of Examples 1-6 can maintain good stability for a significantly longer time, indicating that the release agent provided by the present invention can significantly improve the problem of poor stability of the release agent.

[0129] (2) Demoulding performance test

[0130] According to the performance requirements of the demoulding agent in JC / T 949-2021 "Demoulding Agent for Concrete Products", such as: it should achieve the effects of non-dissolution and non-stickiness after soaking in water. The demoulding agent sample is mixed and diluted with water at a volume ratio of 1:5, and the film-forming time, film-forming water resistance, etc. of the sample are measured. The results are summarized in Table 2 below:

[0131] Table 2 Demoulding performance test of the sample

[0132]

[0133]

[0134] It was found after dilution by the above operations that the particle size distribution of the demoulding agent emulsion in Examples 1-6 was uniform and showed a blue light under sunlight, while the demoulding agent using external emulsification in Comparative Example 3 was a white emulsion.

[0135] It can be seen from the demoulding performance test in Table 2 above that:

[0136] Compared with Comparative Examples 1-3, the demoulding agents prepared in Examples 1-6 showed better demoulding performance as a whole. Specifically, after dilution with water, the demoulding agents in Examples 1-6 had a shorter film-forming time, and when soaked in water, they could all meet the requirements of non-solvent and non-stickiness proposed in JC / T 949-2021. The concrete adhesion amount was also significantly lower, the demoulding was smooth, and the concrete workpieces after demoulding could maintain their edges and corners, and the surface was intact and smooth.

[0137] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A modified vegetable oil-based aqueous mold release agent, characterized in that, It includes modified self-emulsifying epoxy soybean oil, a curing agent and deionized water; The preparation method of the modified self-emulsifying epoxy soybean oil includes the following steps: Mix epoxy soybean oil with a modifier, heat to 100 - 200 °C, and react for 2 - 4 h to obtain the modified self-emulsifying epoxy soybean oil; The preparation method of the modifier includes the following steps: Mix a polymer raw material Ⅰ containing a polyethylene glycol group with a raw material Ⅱ containing a sulfonate group, and prepare the modifier through an addition reaction; the polymer raw material Ⅰ is selected from one or more of polyethylene glycol acrylate, isobutenyl polyethylene glycol, and allyl polyoxyethylene ether, and the raw material Ⅱ is one or more of sodium sulfite or sodium bisulfite; The curing agent includes one or more of diethylenetriamine, triethylenetetramine, 1,6-hexanediamine, and polyetheramine.

2. The modified vegetable oil-based aqueous mold release agent according to claim 1, wherein In the addition reaction, control the temperature at 30 - 80 °C and the reaction time at 60 - 90 min.

3. The modified vegetable oil-based aqueous mold release agent according to claim 1, characterized in that, In the preparation process of the modified self-emulsifying epoxy soybean oil, the mass ratio of epoxy soybean oil to the modifier is 1 - 2:

1.

4. The preparation method of the modified vegetable oil-based aqueous mold release agent according to any one of claims 1 to 3, characterized in that It includes the following steps: Mix the modified self-emulsifying epoxy soybean oil, the curing agent and deionized water, and stir well to obtain the modified vegetable oil-based waterborne release agent.

5. The preparation method of the modified vegetable oil-based aqueous mold release agent according to claim 4, characterized in that, The mass ratio of the modified self-emulsifying epoxy soybean oil, the curing agent and deionized water is 100:2.55 - 7.36:0.24 - 1.2.

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