CN119236465A

CN119236465A - A kind of silicon ether defoamer and preparation method thereof

Info

Publication number: CN119236465A
Application number: CN202411428189.4A
Authority: CN
Inventors: 宋勇; 陈浩南; 曹鑫; 常兴龙; 王喜杰
Original assignee: Deland Water Technology Co ltd
Current assignee: Xinjiang Water Treatment Engineering Technology Research Center Co ltd
Priority date: 2024-10-14
Filing date: 2024-10-14
Publication date: 2025-01-03

Abstract

本发明提供了一种硅醚消泡剂及其制备方法，该消泡剂以质量份数计，主要由以下原料制得：二甲基硅氧烷7‑11份、改性聚醚4‑12份、催化剂1‑7份、乙醇3‑5份、脂肪酸酰胺3‑17份、硅藻土2‑8份，碱液2‑8份，去离子水15‑35份。该消泡剂通过二甲基硅氧烷与改性聚醚缩合反应制得，具有优异的疏水性和低表面张力，能够快速铺展于泡沫表面并破坏其稳定性。从而实现快速消泡、长效抑泡，同时具有良好的环保性和广泛的适用性。The invention provides a siloxane defoamer and a preparation method thereof, wherein the defoamer is mainly prepared from the following raw materials by mass: 7-11 parts of dimethylsiloxane, 4-12 parts of modified polyether, 1-7 parts of catalyst, 3-5 parts of ethanol, 3-17 parts of fatty acid amide, 2-8 parts of diatomaceous earth, 2-8 parts of alkali solution, and 15-35 parts of deionized water. The defoamer is prepared by condensation reaction of dimethylsiloxane and modified polyether, has excellent hydrophobicity and low surface tension, can be quickly spread on the foam surface and destroy its stability. Thus, rapid defoaming and long-term foam suppression are achieved, while having good environmental protection and wide applicability.

Description

Silicone ether defoamer and preparation method thereof

Technical Field

The invention belongs to the technical field of defoamers, and in particular relates to a silyl ether defoamer and a preparation method thereof.

Background

In industrial processes, many processes produce foam which may not only affect the smooth progress of the production process but may also adversely affect the environment. Therefore, the use of defoamers to remove and inhibit foam generation is particularly important. Currently, the widely used defoamers mainly comprise organosilicon defoamers and polyether defoamers, and each of the silicone defoamers and the polyether defoamers has unique advantages and disadvantages.

Organosilicon defoamers are a class of siloxane-based compounds, typically composed of long-chain macromolecules of organic groups with silicon and oxygen atoms. The organic silicon defoamer has excellent defoaming effect and low consumption, and can be used in a wide temperature range. Its surface tension is generally lower than that of water and general foaming liquids, which makes it better in defoaming. However, in certain circumstances, silicone defoamers can cause contamination and adversely affect certain materials. The organosilicon compounds therein may cause safety and environmental problems and thus require special attention in use and storage.

In contrast, the polyether defoamer has relatively high safety, is commonly used in the industries of medicines, foods and the like, is relatively harmless to human bodies and the environment, and can have better applicability under certain specific application scenes. However, polyether defoamers are not ideal in defoaming effect, and in particular for certain high foam liquids, they may not be as effective as silicone defoamers. Is easy to wash away by water, and cannot maintain the defoaming effect for a long time.

There is a need for an antifoaming agent that combines the advantages of both antifoaming agents.

In view of this, the present invention has been made.

Disclosure of Invention

The first object of the invention is to provide a silicone defoaming agent which realizes the effects of quick defoaming and long-acting foam inhibition through the synergistic effect of a silicone compound with a specific structure and a functional additive, and has good environmental protection and wide applicability.

The second aim of the invention is to provide a preparation method of the silicon ether defoamer, which is simple, can realize rapid preparation of products, is economical and environment-friendly, and realizes green economy.

In order to achieve the above object of the present invention, the following technical solutions are specifically adopted:

The invention provides a silyl ether defoamer which is mainly prepared from the following raw materials, by mass, 7-11 parts of dimethyl siloxane, 4-12 parts of modified polyether, 1-7 parts of a catalyst, 2-6 parts of ethanol, 3-17 parts of fatty acid amide, 2-8 parts of diatomite, 2-8 parts of alkali liquor and 15-35 parts of deionized water.

Preferably, as a further specific embodiment, 8-10 parts of dimethyl siloxane, 5-10 parts of modified polyether, 2-5 parts of catalyst, 3-5 parts of ethanol, 5-15 parts of fatty acid amide, 3-6 parts of diatomite, 3-6 parts of alkali liquor and 20-30 parts of deionized water.

Preferably, as a further specific embodiment, 9 parts of dimethyl siloxane, 8 parts of modified polyether, 3 parts of catalyst, 4 parts of ethanol, 10 parts of fatty acid amide, 4 parts of kieselguhr, 5 parts of alkali liquor and 25 parts of deionized water.

The dimethyl siloxane and the modified polyether are taken as reactants to participate in the reaction, the dimethyl siloxane and the modified polyether are produced into products through condensation reaction, the contents of the dimethyl siloxane and the modified polyether are corresponding, when one component is excessive, the content of the other component is inevitably reduced, and finally, the produced products generate unnecessary byproducts, so that the performance of the products is affected. In the present invention, the modified polyether may be one in which Ethylene Oxide (EO) and Propylene Oxide (PO) form long homo-segments and are arranged at intervals on the main chain, and EPE-type or PEP-type polyethers are formed according to the difference of block sequences, or one in which Ethylene Oxide (EO) and Propylene Oxide (PO) are arranged randomly on the molecular chain, the two monomers being randomly distributed on the main chain, and no one monomer being capable of forming a separate long segment on the molecular chain.

In the invention, the ethanol and the fatty acid amide are used as the functional regulator, so that the silicon ether defoamer can be better mutually dissolved with the substances to be defoamed, and the silicon ether defoamer can be dispersed in the substances to be defoamed more uniformly, thereby improving the solubility and the dispersibility of the defoamer and finally achieving the purpose of improving the defoaming performance of the defoamer. Meanwhile, the invention limits the dosage of the two, when the ethanol or the fatty acid amide is excessive, the reaction system is influenced, but the solubility and the dispersibility of the defoaming agent are reduced, when the dosage of the two is small, the improvement of the reaction system is limited, the solubility and the dispersibility of the defoaming agent are reduced, the defoaming agent is difficult to uniformly and stably exist in the substances to be defoamed, and the adaptability is reduced, so that the defoaming and foam inhibition effects of the defoaming agent are influenced.

The diatomite can play a role in stabilizing the defoaming agent, can prevent the defoaming agent from decomposing or precipitating in the long-term storage or use process, and has a certain antibacterial effect. Under excessive conditions, not only is unnecessary waste caused, but also the defoamer is too viscous.

The alkali liquor can influence the crosslinking property of the dimethyl siloxane, and the proper amount of alkali liquor is added into a reaction system to promote the condensation reaction of the dimethyl siloxane and the modified polyether.

Preferably, as a further specific embodiment, the catalyst is any one of sulfuric acid or a resin catalyst.

Preferably, as a further specific embodiment, the lye is sodium hydroxide solution;

Preferably, the lye is 20wt% to 30wt% sodium hydroxide solution;

Preferably, the lye is 25wt% sodium hydroxide solution.

In the actual reaction process, sodium hydroxide or potassium hydroxide can be selected as alkali liquor to participate in the reaction, the concentration and the dosage of the alkali liquor are limited, when the alkali liquor is excessive, the excessive alkali liquor can not promote the reaction, and the alkali liquor has certain corrosiveness, so that the waste is caused, and the environment is easily polluted.

The invention also provides a preparation method of the silyl ether defoamer, which comprises the following steps:

mixing and stirring dimethyl siloxane and modified polyether, heating, then adding a catalyst, and continuously stirring to obtain a silyl ether main body;

Cooling the main body of the silyl ether, adding ethanol and fatty acid amide, and continuously stirring for 25-35 min;

maintaining the temperature after cooling, adding diatomite, and continuously stirring for 1-2 h;

And finally adding deionized water, cooling to 25-35 ℃, and continuously stirring to obtain the product.

Preferably, the stirring time is 30min;

preferably, stirring is continued for 2 hours;

Preferably, the temperature is reduced to 25 ℃.

In the invention, reactants are added to be fully mixed, then a catalyst is added to catalyze the reaction, then a functional regulator is added to improve the reaction product, finally diatomite is added to stably thicken the product, and finally part of ionized water is added to regulate the defoaming agent.

Preferably, as a further specific embodiment, in the step of mixing, stirring and heating the modified polyether, the heating temperature is 117 ℃ to 123 ℃;

Preferably, the heating temperature is 120 ℃.

Preferably, as a further specific embodiment, in the step of cooling the silyl ether main body, the temperature of cooling is 40 ℃ to 50 ℃;

Preferably, the temperature of the cooling is 45 ℃.

Preferably, as a further specific embodiment, in the step of cooling to 25 ℃ to 35 ℃ and continuously stirring, the stirring time is 25min to 35min;

preferably, the stirring time is 30min.

Preferably, as a further specific embodiment, in the step of adding the catalyst and continuously stirring, the stirring time is 3h to 4h;

preferably, the stirring time is 4 hours.

The reaction temperature and the stirring time are limited in the invention, on one hand, the excessive temperature can easily cause the self-decomposition of the reactant and can not produce the defoamer, on the other hand, the excessive temperature can cause the reaction to be too intense to control the reaction, and finally, when the reaction temperature exceeds the limiting value, the unknown and difficult-to-separate organic matters are easily generated, so that the defoamer can not be obtained.

In the case of stirring time, the stirring is likely to cause bubbles in the reaction system over time, thereby reducing the quality of the antifoaming agent.

Compared with the prior art, the invention has the beneficial effects that:

(1) The defoamer is prepared by condensation reaction of dimethyl siloxane and modified polyether, has excellent hydrophobicity and low surface tension, and can be rapidly spread on the surface of foam and destroy the stability of the foam. Thereby realizing quick defoaming and long-acting foam inhibition, and simultaneously having good environmental protection and wide applicability.

(2) The preparation method is simple, can effectively reduce environmental pollution, and simultaneously improves the preparation efficiency and ensures the stability of the product.

Detailed Description

The technical solution of the present invention will be clearly and completely described in conjunction with the specific embodiments, but it will be understood by those skilled in the art that the examples described below are some, but not all, examples of the present invention, and are intended to be illustrative only and should not be construed as limiting the scope of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.

Example 1

7G of dimethyl siloxane and 4g of modified polyether are taken and added into a reaction kettle, the mixture is heated to 117 ℃, then 1g of sulfuric acid is added into the mixture, and stirring is continued for 3 hours, so that a silyl ether main body is obtained;

The silyl ether main body is cooled to 40 ℃, 2g of ethanol and 3g of fatty acid amide are added into a reaction kettle, and stirring is continued for 25min;

Maintaining the temperature at 40 ℃, adding 3g of 20wt% sodium hydroxide solution and 3g of diatomite into a reaction kettle, and continuously stirring for 1h;

And finally, adding 15g of deionized water into the reaction kettle, and cooling to 25 ℃ to obtain the product.

Example 2

Adding 11g of dimethyl siloxane and 12g of modified polyether into a reaction kettle, heating to 123 ℃, then adding 7g of sulfuric acid into the reaction kettle, and continuously stirring for 4 hours to obtain a silyl ether main body;

The silyl ether main body is cooled to 50 ℃, 6g of ethanol and 17g of fatty acid amide are added into a reaction kettle, and stirring is continued for 25min;

Maintaining the temperature at 40 ℃, adding 8g of 20wt% sodium hydroxide solution and 8g of diatomite into a reaction kettle, and continuously stirring for 1h;

And finally, adding 35g of deionized water into the reaction kettle, and cooling to 35 ℃ to obtain the product.

Example 3

Adding 5g of dimethyl siloxane and 2g of modified polyether into a reaction kettle, heating to 120 ℃, then adding 2g of sulfuric acid into the reaction kettle, and continuously stirring for 4 hours to obtain a silyl ether main body;

the silyl ether main body is cooled to 45 ℃, 3g of ethanol and 5g of fatty acid amide are added into a reaction kettle, and stirring is continued for 25min;

Maintaining the temperature at 40 ℃, adding 3g of 30wt% sodium hydroxide solution and 3g of diatomite into a reaction kettle, and continuously stirring for 2 hours;

And finally, adding 20g of deionized water into the reaction kettle, and cooling to 25 ℃ to obtain the product.

Example 4

maintaining the temperature at 40 ℃, adding 3g of 25wt% sodium hydroxide solution and 3g of diatomite into a reaction kettle, and continuously stirring for 2 hours;

Example 5

9G of dimethyl siloxane and 8g of modified polyether are taken and added into a reaction kettle, heated to 120 ℃, then 3g of sulfuric acid is added into the reaction kettle, and stirring is continued for 4 hours, so as to obtain a silyl ether main body;

the silyl ether main body is cooled to 45 ℃, 4g of ethanol and 10g of fatty acid amide are added into a reaction kettle, and stirring is continued for 25min;

Maintaining the temperature at 40 ℃, adding 5g of 25wt% sodium hydroxide solution and 4g of diatomite into a reaction kettle, and continuously stirring for 2 hours;

and finally, adding 25g of deionized water into the reaction kettle, and cooling to 25 ℃ to obtain the product.

Example 6

The specific embodiment was consistent with example 5, replacing the catalyst with an equal mass resin catalyst only.

Example 7

A specific embodiment was consistent with example 5, changing only the concentration of sodium hydroxide solution to 45wt%.

Example 8

The specific embodiment is consistent with example 5, changing only the concentration of sodium hydroxide solution to 10wt%.

Example 9

Specific embodiments were consistent with example 5, with the reaction conditions being varied, as shown in table 1.

TABLE 1 variation of reaction conditions

Comparative example 1

The specific embodiment was consistent with example 5, and the amounts of each material were varied as shown in table 2.

TABLE 2 variation of the amount of each substance

Comparative example 2

Commercially available common defoamers are selected, and the main components of the defoamer are an emulsifier, a carrier, an emulsifying aid and an active ingredient.

Experimental example 1

Uniformly mixing sodium dodecyl sulfate, tween 80 and lecithin according to the ratio of 1:1:1, preparing an aqueous solution with the mass concentration of 1% to serve as foaming liquid, introducing air into 100mL of foaming liquid in a 500mL measuring cylinder with the constant temperature of 50 ℃ in a constant-temperature water bath by using an air pump, stopping ventilation when the foam amount reaches 500mL, simultaneously adding 0.1g of defoaming agent for defoaming, and recording the time when the agent is added to foam, wherein the time is defoaming time. The bubbling was continued and time was recorded when the foam again reached 500 mL. And simultaneously, the stability of the prepared defoamer is tested.

The experimental results are shown in tables 3 and 4.

TABLE 3 experimental results of defoaming time and foam suppressing time of examples

TABLE 4 Experimental results of comparative examples defoaming time and foam suppressing time

From the above data, the following conclusions can be drawn:

Comparing example 5 with schemes 1 to 4 in comparative example 1, it can be seen that the occurrence of too much or too little of a certain component in the present invention affects the defoaming performance and the foam suppressing performance of the defoaming agent. The dimethyl siloxane and the modified polyether are reactants of the invention, so that when the content of any component of the dimethyl siloxane and the modified polyether is too high, the dimethyl siloxane and the modified polyether can be decomposed at high temperature, and the decomposed product can generate uncontrollable other reactions, which can be reflected from experimental data, when the dosage of the dimethyl siloxane and the modified polyether is changed, the defoaming time and the foam inhibition time of the generated defoaming agent are prolonged, the purity of the product can be reflected from the side surface, and the performance of the defoaming agent is influenced. In addition, since the impurities are more, the stability of the defoamer is also negatively affected.

As can be seen by comparing example 5 with schemes 3-8 of comparative example 1, the functional additive can affect the stability of the defoamer to a greater extent. The experimental data can intuitively show that when the components are changed, the defoaming time is prolonged, the foam inhibition time is reduced, the stability is reduced, the data can be reflected from the side, and the functional additive can adjust the performance of the foam inhibitor, so that the purpose of improving the defoaming performance of the foam inhibitor is achieved.

The solubility and the dispersibility of the defoaming agent can be increased by the ethanol and the fatty acid amide, so that the defoaming agent can form a uniform and stable phase with a substance to be defoamed, the working efficiency of the defoaming agent is improved, and the purpose of adjusting the performance of the defoaming agent is achieved.

As can be seen from a comparison of the embodiment 5 with the embodiment 9-10 of the comparative example 1, the diatomaceous earth is selected mainly from the aspect of long-term storage of the antifoaming agent, and the diatomaceous earth is added to exert a stabilizing effect on the antifoaming agent when it is stored for a long period of time, and can effectively prevent decomposition, precipitation or delamination of the antifoaming agent during long-term storage or use. It can also be seen from the experimental data that diatomaceous earth does not directly affect the performance of the defoamer, but directly affects its stability.

Comparing example 5 with schemes 11-12 of comparative example 1, an appropriate amount of alkali solution was added to promote condensation between dimethylsiloxane and polyether during the experiment, and the improvement of condensation was lower when the content was lower, resulting in slightly longer defoaming time, and excessive amount did not affect the reaction but caused unnecessary waste.

It should be noted that the above embodiments are merely for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that the technical solution described in the above embodiments may be modified or some or all of the technical features may be equivalently replaced, and these modifications or substitutions do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present invention.

Claims

1. A silicone ether defoamer, characterized in that it is mainly made from the following raw materials, by weight: 7-11 parts of dimethylsiloxane, 4-12 parts of modified polyether, 1-7 parts of catalyst, 2-6 parts of ethanol, 3-17 parts of fatty acid amide, 2-8 parts of diatomaceous earth, 2-8 parts of alkali solution, and 15-35 parts of deionized water.

2. The silicone ether defoamer according to claim 1, characterized in that it comprises 8-10 parts of dimethylsiloxane, 5-10 parts of modified polyether, 2-5 parts of catalyst, 3-5 parts of ethanol, 5-15 parts of fatty acid amide, 3-6 parts of diatomaceous earth, 3-6 parts of alkali solution, and 20-30 parts of deionized water.

3. The silicone ether defoamer according to claim 1, characterized in that it comprises 9 parts of dimethylsiloxane, 8 parts of modified polyether, 3 parts of catalyst, 4 parts of ethanol, 10 parts of fatty acid amide, 4 parts of diatomaceous earth, 5 parts of alkali solution, and 25 parts of deionized water.

4. The silicone ether defoamer according to claim 1, characterized in that the catalyst is any one of sulfuric acid or a resin catalyst.

5. The silicone ether defoamer according to claim 1, characterized in that the alkali solution is a sodium hydroxide solution;

Preferably, the alkali solution is a 20wt%-30wt% sodium hydroxide solution;

Preferably, the alkali solution is a 25wt% sodium hydroxide solution.

6. A method for preparing the silicone ether defoamer according to any one of claims 1 to 5, characterized in that it comprises the following steps:

The dimethylsiloxane and the modified polyether are mixed, stirred and heated, and then a catalyst is added and stirred continuously to obtain a silyl ether main body;

The silyl ether body is cooled, and ethanol and fatty acid amide are added and stirred for 25-35 minutes;

Keep the temperature after cooling, add diatomaceous earth, and continue stirring for 1h-2h;

Finally, add deionized water, cool to 25°C-35°C, and continue stirring to obtain the mixture.

7. The method for preparing a silicone ether defoamer according to claim 6, characterized in that in the step of mixing, stirring and heating the modified polyether, the heating temperature is 117°C-123°C.

8. The method for preparing a silicone ether defoaming agent according to claim 6, characterized in that in the step of cooling the silicone ether body, the cooling temperature is 40°C-50°C.

9. The method for preparing a silicone ether defoaming agent according to claim 6, characterized in that in the step of cooling to 25°C-35°C and continuously stirring, the stirring time is 25min-35min.

10. The method for preparing a silicone ether defoamer according to claim 6, characterized in that in the step of adding the catalyst and continuously stirring, the stirring time is 3h-4h.