Polyether supported, self-emulsifying silicone paste and method of making same
By introducing polyether structures and MQ resin into silicone paste, a self-emulsifying silicone paste was constructed, which solved the problem of poor stability of traditional silicone paste in harsh environments and achieved the effects of spontaneous dispersion and rapid defoaming in water and oil two-phase systems.
Patent Information
- Application Number
- CN202611141563.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-30
- Publication Date
- 2026-11-06
AI Technical Summary
Traditional silicone defoamers are prone to emulsion demulsification and stratification in high-temperature, strong acid and alkali, or high electrolyte concentration environments, resulting in loss of defoaming performance. They also require additional emulsifiers to maintain stability and cannot adapt to the changing industrial environment.
By introducing a polyether structure into the silicone paste, a multi-branched ladder structure is constructed through hydrosilylation and siloxane rearrangement reactions. The HLB value is adjusted to allow it to spontaneously disperse in water or oil, forming a self-emulsifying silicone paste. The stability is enhanced by combining it with MQ resin.
It achieves spontaneous dispersion in both water-based and oil-based systems, exhibits rapid defoaming, high stability, strong anti-demulsification ability, and adaptability to diverse industrial environments.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of defoamer technology, and in particular to a polyether-supported, self-emulsifying silicone paste and its preparation method. Background Technology
[0002] In industrial production processes such as chemical, pharmaceutical, textile, and wastewater treatment, foam generation often hinders mass and heat transfer, reduces equipment utilization, lowers product performance and quality, and can even lead to production accidents. Defoamers can rapidly reduce the local surface tension of foam, making them the most direct and effective means of eliminating industrial foam.
[0003] Currently, silicone defoamers are widely used due to their low surface tension and rapid defoaming. Traditional silicone defoamers typically consist of dimethyl silicone oil, silica, and emulsifiers. These products must undergo high-speed shear emulsification before use, and because they rely on external emulsifiers to maintain stability, the emulsion is prone to demulsification and separation under harsh environments such as high temperature, strong acids and alkalis, or high electrolyte concentrations, leading to a loss of defoaming performance.
[0004] To address these issues, existing technologies typically improve compatibility by introducing polyether-modified silicone oils. However, simple polyether modification often results in products with excessive hydrophilicity, leading to a loss of defoaming ability, or a simple structure that cannot adapt to changing industrial environments.
[0005] Therefore, developing a self-emulsifying silicone paste that requires no additional emulsifiers, has good dispersibility, and stable performance is an urgent problem to be solved in this field. Summary of the Invention
[0006] To address the aforementioned technical problems, this invention provides a polyether-supported, self-emulsifying silicone paste and its preparation method. The polyether structure supported in the silicone paste can alter the original hydrophilic / lipophilic balance (HLB) value of the silicone paste, making it easier to disperse in a dispersant. When used as a defoamer, it exhibits more stable performance and excellent anti-demulsification ability.
[0007] To achieve this technical objective, the present invention adopts the following solution: In a first aspect, the present invention provides a method for preparing a polyether-supported, self-emulsifying silicone paste, comprising: a hydrosilylation reaction of hydrogen-containing silicone oil, vinyl silicone oil, and polyether under the action of catalyst A to obtain product I; a siloxane rearrangement reaction of methyl silicone oil, methyltriethoxysilane, and MQ resin under the action of catalyst B; and termination of the reaction by adding silica and a terminator to obtain the polyether-supported, self-emulsifying silicone paste product; specifically including the following steps: S1. Add hydrogen-containing silicone oil, vinyl silicone oil and polyether to the reactor, stir evenly and heat to 60~120℃, add catalyst A and react for 0.5~2h to obtain product I; S2. Add methyl silicone oil, methyltriethoxysilane and MQ resin to product I, heat to 110~135℃, add catalyst B, and continue the reaction until the system viscosity is ≥20000CS; S3. Add silica and stir for at least 30 minutes. Add a reaction terminator to deactivate catalyst B. Cool to room temperature to obtain polyether-supported, self-emulsifying silicone paste.
[0008] Furthermore, by mass parts, the amount of hydrogen-containing silicone oil is 60-80 parts, vinyl silicone oil is 30-40 parts, polyether is 40-80 parts, methyl silicone oil is 50-150 parts, methyltriethoxysilane is 10-40 parts, MQ resin is 10-20 parts, and silica is 0.5-1.5 parts.
[0009] Furthermore, the hydrogen content of the hydrogen-containing silicone oil is 0.05~0.2%; the vinyl silicone oil is an end-vinyl silicone oil or a side-vinyl silicone oil with different vinyl contents; the polyether is selected from one or more of the E-series polyethers (polyoxyethylene ether) or the P-series polyethers (polyoxypropylene ether), with a molecular weight of 400~3000; the methyl silicone oil is preferably a methyl silicone oil with a viscosity of 350CS, but other methyl silicone oils with different viscosities can also be used.
[0010] Furthermore, catalyst A is a platinum complex catalyst, and its amount is 0.5% of the total mass of the reactants in step S1; catalyst B is a KOH alkaline gel catalyst, and its amount is 1% of the total product mass; the terminator is phosphoric acid, and its amount is 10% of the mass of catalyst B.
[0011] Furthermore, product I has a multi-branched ladder structure. This structure gives product I stronger self-emulsifying properties and makes it easier to graft into the second reaction step. One structural formula of product I is: Where n = 5~30; One structure of the prepared polyether-supported, self-emulsifying silicone paste is as follows: Where m = 20~80, n = 5~30.
[0012] Secondly, the present invention provides a polyether-supported, self-emulsifying silicone paste, which is obtained by the aforementioned method for preparing polyether-supported, self-emulsifying silicone paste.
[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention grafts polyether onto the silicone paste skeleton, adjusting the HLB value of the product in situ. The polyether segments act as an emulsifier, enabling the silicone paste to spontaneously disperse in water or oil without the need for additional emulsifiers and co-emulsifiers.
[0014] This invention allows for the control of the HLB value of silicone paste by adjusting the type and proportion of polyether, making the paste suitable for both aqueous and oil-based systems. If the loaded polyether contains more hydrophilic polyether, the product has good water solubility, and water can be used as a dispersant to eliminate foam generated in aqueous solutions in general production and daily life. If the loaded polyether contains more lipophilic polyether, the product is easily dispersed in the oil phase, and foam generated in the oil phase can be quickly eliminated after dissolving the silicone paste with solvents such as dodecene.
[0015] This invention utilizes a process of first reacting to thicken the product and then adding silica to construct a stable multi-branched ladder structure in combination with MQ resin. This effectively inhibits the migration and exudation of silicone oil, and the product exhibits stable performance in accelerated aging tests. Detailed Implementation
[0016] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.
[0017] Unless otherwise specified, the experimental methods used in the embodiments and comparative examples of this invention are conventional methods. Unless otherwise specified, the materials and reagents used are commercially available.
[0018] This invention provides a method for preparing a polyether-supported, self-emulsifying silicone paste. The method involves a hydrosilylation reaction of hydrogen-containing silicone oil, vinyl silicone oil, and polyether under the action of catalyst A to obtain product I. Based on product I, a siloxane rearrangement reaction is carried out using methyl silicone oil, methyltriethoxysilane, and MQ resin under the action of catalyst B. The reaction is terminated by adding silica and a terminator to obtain the polyether-supported, self-emulsifying silicone paste product. The method specifically includes the following steps: S1. Add 60-80 parts of hydrogen-containing silicone oil (hydrogen content 0.05-0.2%), 30-40 parts of vinyl silicone oil, and 40-80 parts of polyether to the reactor. After stirring evenly, heat to 60-120℃, add catalyst A (platinum complex catalyst, the amount added is 0.5% of the total amount of reactants in this step), and react for 0.5-2 hours to obtain product I. The vinyl silicone oil is an end-vinyl silicone oil or a side-vinyl silicone oil with different vinyl contents; the polyether is selected from one or more of the E-series polyethers or the P-series polyethers, specifically E100, E200, E500, E800, E1000, E2000, P50, P150, P300, P600 or P1000. S2. Add 50-150 parts of methyl silicone oil (preferably with a viscosity of 350 CS), 10-40 parts of methyltriethoxysilane and 10-20 parts of MQ resin to product I obtained in step S1, heat to 110-135℃, add catalyst B (KOH alkaline gel catalyst, the amount added is 1% of the total mass of the product), and continue the reaction until the viscosity of the system is ≥20000 CS; S3. After the reaction system reaches the expected viscosity, add 0.5~1.5 parts of silica, stir for at least 30 minutes, add reaction terminator (phosphoric acid, the amount added is 10% of the mass of catalyst B) to deactivate catalyst B, cool to room temperature, and obtain polyether supported self-emulsifying silicone paste. Example 1
[0019] S1. Preparation of Product I: 60 parts of hydrogen-containing silicone oil (0.08% hydrogen content), 30 parts of vinyl silicone oil, and 20 parts of E100, 30 parts of E200, 5 parts of E500, 10 parts of E800, and 5 parts of E1000 polyethers were added to a reactor. The mixture was stirred until homogeneous and heated to 100°C. 0.5% (by weight) of a platinum complex catalyst from this step was added to the reactor, and the reaction was allowed to proceed for 2 hours to obtain Product I.
[0020] S2, Siloxane rearrangement reaction: Add 100 parts of methyl silicone oil, 10 parts of methyltriethoxysilane, and 10 parts of MQ803 resin to product I, stir and heat to 130℃, add 1% of KOH alkaline gel catalyst of the total product mass, and continue the reaction.
[0021] S3. After the reaction system reaches 20000CS (30 min after catalyst B is added), add 1 part of fumed silica and stir for 30 min; add phosphoric acid (10% of the mass of KOH alkaline gel catalyst) to neutralize the catalyst. After neutralization, heat to 150℃ and stir for 2 h to strengthen the grafting reaction and improve product stability. After 2 h, stop heating and cool to room temperature to obtain the silicone paste product. Example 2
[0022] S1. Preparation of Product I: 60 parts of hydrogen-containing silicone oil (0.08% hydrogen content), 30 parts of vinyl silicone oil, and 25 parts of P50, 5 parts of P150, 5 parts of P300, and 5 parts of P600 polyether were added to a reactor, stirred until homogeneous, and heated to 100°C. 0.5% (by mass) of a platinum complex catalyst from this step was added to the reactor, and the reaction was carried out for 2 hours to prepare Product I.
[0023] S2, Siloxane rearrangement reaction: Add 100 parts of methyl silicone oil, 10 parts of methyltriethoxysilane, and 10 parts of MQ803 resin to product I, stir and heat to 130℃, add 1% of KOH alkaline gel catalyst of the total product mass, and continue the reaction.
[0024] S3. After the reaction system reaches 20000CS, add 1 part of fumed silica and stir for 30 min. Add phosphoric acid (10% of the mass of KOH alkaline gel catalyst) to neutralize the catalyst. After neutralization, heat to 150℃ and stir for 2 h to strengthen the grafting reaction and improve product stability. After 2 h, stop heating and cool to room temperature to obtain the silicone paste product. Example 3
[0025] S1. Preparation of Product I: 80 parts of hydrogen-containing silicone oil with a hydrogen content of 0.18%, 40 parts of vinyl silicone oil, and 5 parts of E100, 10 parts of E200, 25 parts of E500, 15 parts of E800, 20 parts of E1000, and 30 parts of E2000 polyether were added to a reactor, stirred and mixed evenly, and heated to 100°C. 0.5% (by weight) of a platinum complex catalyst from this step was added to the reactor, and the reaction was carried out for 2 hours to prepare Product I.
[0026] S2, Siloxane rearrangement reaction: Add 50 parts of methyl silicone oil, 40 parts of methyltriethoxysilane, and 20 parts of MQ803 resin to product I, stir and heat to 130℃, add 1% of KOH alkaline gel catalyst of the total product mass, and continue the reaction.
[0027] S3. After the reaction system reaches 20000CS, add 1 part of fumed silica and stir for 30 min. Add phosphoric acid (10% of the mass of KOH alkaline gel catalyst) to neutralize the catalyst. After neutralization, heat to 150℃ and stir for 2 h to strengthen the grafting reaction and improve product stability. After 2 h, stop heating and cool to room temperature to obtain the silicone paste product. Example 4
[0028] S1. Preparation of Product I: 80 parts of hydrogen-containing silicone oil with a hydrogen content of 0.18%, 40 parts of vinyl silicone oil, and 5 parts of P50, 10 parts of P150, 15 parts of P300, 25 parts of P600, and 15 parts of P1000 polyether were added to a reactor, stirred and mixed evenly, and heated to 100°C. 0.5% (by weight) of a platinum complex catalyst from this step was added to the reactor, and the reaction was carried out for 2 hours to prepare Product I.
[0029] S2, Siloxane rearrangement reaction: Add 150 parts of methyl silicone oil, 30 parts of methyltriethoxysilane, and 20 parts of MQ803 resin to product I, stir and heat to 130℃, add 1% of KOH alkaline gel catalyst of the total product mass, and continue the reaction.
[0030] S3. After the reaction system reaches 20000CS, add 1 part of fumed silica and stir for 30 min. Add phosphoric acid (10% of the mass of KOH alkaline gel catalyst) to neutralize the catalyst. After neutralization, heat to 150℃ and stir for 2 h to strengthen the grafting reaction and improve product stability. After 2 h, stop heating and cool to room temperature to obtain the silicone paste product. Comparative Example 1
[0031] Prepared using conventional methods: 100 parts of dimethyl silicone oil, 3 parts of emulsifier (Span-80 / Tween-60 compound) and 5 parts of silica were emulsified by high-speed shearing to obtain conventional emulsified silicone paste. Comparative Example 2
[0032] The difference compared to Example 1 is that no polyether is added in step S1. Comparative Example 3
[0033] The difference compared to Example 2 is that MQ resin is not added in step S2. Performance testing:
[0034] The silicone pastes prepared in each embodiment and comparative example were tested as follows, and the test results are shown in Table 1.
[0035] Dispersibility: Take 10g of sample and add it to 40g of dispersant (the dispersant is deionized water or dodecene solution), stir at low speed, and visually observe the ease of dispersion and the state of the emulsion.
[0036] Defoaming time: The time (s) after adding the sample was recorded using the bubbling method to ensure that the foam completely disappeared.
[0037] Foam suppression performance: Add the sample to the foam generation system and record the height of the foam layer (mm) after continuous bubbling for 5 minutes.
[0038] Stability: Centrifugation (3000 rpm, 30 min) and storage at room temperature for 6 months were used to observe whether stratification or demulsification occurred.
[0039] Table 1 Performance test results of each embodiment and comparative example
[0040] As shown in Table 1, the silicone pastes prepared in Examples 1-4 of this invention, which incorporate polyether segments, all exhibit excellent self-emulsifying capabilities and can spontaneously disperse in water or oil without high-speed shearing. In terms of defoaming speed, the products of this invention are significantly faster than traditional silicone pastes. Regarding stability, the "emulsified" structure introduced through chemical bonding in the products of this invention provides far superior resistance to demulsification and storage stability compared to traditional products that rely on physically mixed emulsifiers.
[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; if these modifications and variations fall within the scope of the claims of the present invention and their equivalents, they should all be considered to be within the protection scope of the present invention.
Claims
1. A method for preparing a polyether-supported, self-emulsifying silicone paste, characterized in that, Includes the following steps: S1. Add hydrogen-containing silicone oil, vinyl silicone oil and polyether to the reactor, stir evenly and heat to 60~120℃, add catalyst A and react for 0.5~2h to obtain product I; S2. Add methyl silicone oil, methyltriethoxysilane and MQ resin to product I, heat to 110~135℃, add catalyst B, and continue the reaction until the system viscosity is ≥20000CS; S3. Add silica and stir for at least 30 minutes. Add a reaction terminator to deactivate catalyst B. Cool to room temperature to obtain polyether-supported, self-emulsifying silicone paste.
2. The method for preparing polyether-supported, self-emulsifying silicone paste according to claim 1, characterized in that, By weight, the components are: 60-80 parts hydrogen-containing silicone oil, 30-40 parts vinyl silicone oil, 40-80 parts polyether, 50-150 parts methyl silicone oil, 10-40 parts methyltriethoxysilane, 10-20 parts MQ resin, and 0.5-1.5 parts silica.
3. The method for preparing polyether-supported, self-emulsifying silicone paste according to claim 1, characterized in that, The hydrogen content of the hydrogen-containing silicone oil is 0.05~0.2%; the polyether is selected from one or more of the E-series polyethers or the P-series polyethers, with a molecular weight of 400~3000.
4. The method for preparing polyether-supported, self-emulsifying silicone paste according to claim 1, characterized in that, Catalyst A is a platinum complex catalyst, and its dosage is 0.5% of the total mass of the reactants in step S1; catalyst B is a KOH alkaline gel catalyst, and its dosage is 1% of the total product mass; the terminator is phosphoric acid, and its dosage is 10% of the mass of catalyst B.
5. A polyether-supported, self-emulsifying silicone paste, characterized in that, It is obtained by the preparation method of polyether-supported, self-emulsifying silicone paste according to any one of claims 1-4.