CN110643027B - A kind of wetting and defoaming assistant and preparation method thereof - Google Patents

Abstract

The invention belongs to the field of functional materials, and specifically discloses a wetting and defoaming assistant and a preparation method thereof. In the present invention, under the protection of inert gas, diol, ε-caprolactone and stannous octoate are placed in a reactor, and the reaction is carried out at 100-130 DEG C for 24-72 hours to obtain hydroxyl polycaprolactone; methylaminopyridine and 10-40 ℃, hydroxy polycaprolactone and maleic anhydride are esterified in a solution; under the action of an initiator, the product is then reacted with 3-mercaptopropionic acid to obtain a wetting and defoaming aid . In the system of unsaturated resin-inorganic filler, the wetting and defoaming additive exhibits excellent wetting and defoaming performance, does not affect the curing speed of the unsaturated resin, and also improves the mechanical properties of the cured material.

Description

A kind of wetting and defoaming assistant and preparation method thereof

technical field

The invention relates to a wetting and defoaming assistant belonging to the field of functional polymer materials, in particular to a method for synthesizing a high molecular weight polycaprolactone containing multiple carboxyl groups and the application of the wetting and defoaming assistant for inorganic fillers.

Background technique

Adding powdery inorganic fillers to polymer materials can significantly reduce the cost of products, improve hardness, wear resistance or give products other special functions. Therefore, in the field of modified polymer materials, inorganic fillers are widely used. In order to uniformly disperse the inorganic particles in the polymer material, it is often necessary to supplement processes such as grinding and mechanical stirring. However, these processes will bring a large amount of air into the mixed system of inorganic particles and polymer materials in the form of bubbles. If the air bubbles are not expelled in time, the air bubbles will affect the appearance and mechanical properties of the product. In industry, the strategy of adding defoaming agent and defoaming agent is adopted to reduce the influence of bubbles on modified polymer materials. According to the mechanism of action, antifoaming agents can be subdivided into antifoaming agents, defoaming agents and foam breaking agents.

The defoaming efficiency is the main inspection index for defoamer designers and users to evaluate defoaming performance and screen defoamer products. In pursuit of higher defoaming efficiency, designers design defoamer products as compounds with lower surface tension and poor compatibility with matrix resins (such as fluorine-modified silicone products). However, these compounds with low surface tension and poor compatibility with the matrix resin have caused many new problems, such as reducing the surface tension of the matrix resin, delaying the curing reaction speed of the system, and weakening the mechanical properties of the resin matrix composites. problem.

SUMMARY OF THE INVENTION

The purpose of the present invention is to solve the shortcomings existing in the prior art, and proposes a wetting and defoaming aid and a synthesis method thereof. The prepared polycarboxy polycaprolactone wetting and defoaming aid is compatible with matrix resin. It has good properties and can be adjusted flexibly; the surface tension of its solution is high, which does not affect the mechanical properties of the matrix material and the adhesion of other materials on its surface; It is higher, and at the same time reduces many problems caused by poor compatibility between different types and different functional additives.

In order to realize one of the purposes of the invention, the technical scheme of the product is as follows:

Polycarboxy polycaprolactone wetting and defoaming auxiliary, the general structural formula is (I) or (II):

(其中m、o、p为正整数)中的任意一种。Among them, n is a positive integer, and 400≤n≤500; R is selected from

(where m, o, and p are positive integers) any of them.

In order to realize the second purpose of the invention, the technical scheme of the product preparation method is as follows:

The synthetic method of above-mentioned wetting and defoaming auxiliary agent, comprises the following steps:

S1: place glycol, ε-caprolactone and stannous octoate in a reactor under an inert atmosphere, and react at 100-130° C. for 24-72 hours to obtain polycaprolactone with hydroxyl groups at both ends of the molecule;

S2: after dissolving the polycaprolactone with hydroxyl groups at both ends of the molecule obtained in step S1 with a solvent, adding maleic anhydride, and reacting for 24-72 hours at 4-dimethylaminopyridine and 10-40° C. to the end of the reaction to obtain the solution to be precipitated,

The obtained solution to be precipitated is precipitated in a precipitant, the solid precipitate is collected and dried in a vacuum oven to constant weight to obtain a product;

S3: dissolving the product obtained in step 2 with a solvent, then adding 3-mercaptopropionic acid and an initiator, and reacting at 60-90 ° C for 6-48 hours to the end of the reaction,

After the reaction, remove the solvent of the reaction product with a rotary evaporator to obtain a solution to be precipitated, precipitate the solution to be precipitated in a precipitant, collect the solid precipitate, and put it in a vacuum oven to a constant weight to obtain a polycarboxy polymer. caprolactone;

in,

The diol is 1,2-ethylene glycol, 1,2-propanediol, 1,4-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, 2-methyl alcohol base-1,4-butanediol, 1,6-hexanol, 3,6-octanediol, 1,8-octanediol, 1,4-terephthalenediethanol, 1,4-terephthalene Alcohol, 2,3,5,6-tetrafluoroterephthalic alcohol, 1,4-cyclohexyldiethanol, polyethylene glycol, polypropylene glycol, polyethylene glycol-co-polypropylene glycol, polytetrahydrofuran glycol any one or more mixtures of;

The solvent is a mixture of any one or more of 1,4-dioxane, tetrahydrofuran, N,N-dimethylformamide and chloroform;

The initiator is azobisisobutyronitrile, azobisisoheptanenitrile, azobiscyanovaleric acid, dimethylazobisisobutyrate, 2,2'-azobis(4-methoxy -2,4-dimethylvaleronitrile) any one or more mixtures thereof;

Described precipitating agent is the mixture of ether and petroleum ether, or the mixture of methyl alcohol and ethanol;

and,

The mol ratio of described dihydric alcohol, ε-caprolactone, stannous octoate, maleic anhydride, 4-dimethylaminopyridine and 3-mercaptopropionic acid is 1:(800-1000):(0.02-2): (4-10):(0.2-1):(3-10);

The added mass of the initiator is 5%-50% of the mass of 3-mercaptopropionic acid.

Preferably, the mass ratio of the precipitating agent petroleum ether to ether is 1:1 to 100, the mass ratio of the precipitating agent ethanol to methanol is 1:1 to 100, and the mass ratio of the solution to be precipitated and the precipitating agent in step S2 or S3 is The ratio is 1:50-200.

Preferably, the inert gas is helium or nitrogen.

In order to realize the third purpose of the invention, the technical scheme of product use is as follows:

The polycarboxy polycaprolactone is used as a wetting and defoaming aid for an unsaturated resin-inorganic filler system.

The high molecular weight polycarboxylated polycaprolactone synthesized by the invention has good compatibility with unsaturated resins and is suitable for unsaturated polyester systems; the theoretical acid value is small, which does not affect the curing speed of the inorganic particle filling system; the surface tension is high, It can eliminate the interface between inorganic particles and unsaturated resin, and can improve the mechanical properties of the cured material.

The key of the present invention lies in the structure design and molecular weight control of the polycarboxyl polycaprolactone molecule. Further analysis shows that the two ends of the polycaprolactone molecular chain of the present invention are each connected with two carboxyl groups, and multiple carboxyl groups are simultaneously anchored on the surface of the inorganic particles to bend the polycaprolactone molecular chain. There is no bond between the molecular chains, so that the polymer molecular chain at the bent end can swing continuously relative to the end fixed on the surface of the inorganic particles under the action of thermal motion, so that the bubbles on the surface of the inorganic particles can quickly merge and rise rapidly. At the same time, the molecular weight of the polycarboxylated polycaprolactone synthesized by the present invention is as high as 80-100kg/mol, and the compatibility between the polycarboxylated polycaprolactone of the present invention and the unsaturated resin of the matrix resin can be estimated by Scott theory. The property becomes poor (mixing free energy ΔG _mix > 0), so that the bent polycaprolactone molecular chain and the matrix resin are in a critical state of "compatibility and incompatibility", which can prevent the discharged bubbles from Polycaprolactone adheres to the molecular chain, and can induce small bubbles to fuse with each other into large bubbles and be discharged.

In addition, the polycarboxyl polycaprolactone molecular chain of the present invention is as high as 80-100kg/mol, but the theoretical value of its acid value is only 2.24-2.80mgKOH/g, therefore, it is used as a wetting and defoaming aid (polymeric When the dosage is less than 1%), the acid value of the unsaturated resin will not be significantly changed, and the curing reaction of the unsaturated resin will not be affected.

Beneficial effects:

The polycarboxy polycaprolactone auxiliary agent of the present invention has obvious effects on reducing the content of air bubbles in the system and improving the mechanical properties of the cured material. Moreover, the particularly outstanding advantage is that after adding the polycarboxy polycaprolactone wetting and defoaming auxiliary agent of the present invention, it not only does not affect the curing reaction speed of the unsaturated resin, but also improves the mechanical properties of the curing system, such as compressive strength as high as 58.19MPa, the bending strength reaches 21.5MPa, and the tensile strength is 47.6MPa.

When the present invention is used as a wetting and defoaming auxiliary agent (the amount of polymer is less than 1%), the acid value of the unsaturated resin will not be significantly changed, and the curing reaction of the unsaturated resin will not be affected.

The synthesis method of the invention is simple, the synthesized high-molecular-weight polycaprolactone has high surface tension, and has both functions of wetting and defoaming. The bubbles can be removed during the dispersion process of the inorganic filler, which can effectively prevent the bubbles from stably existing in the system.

Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the description, claims and drawings.

Description of drawings

The accompanying drawings are used to provide a further understanding of the technical solutions of the present invention, and constitute a part of the specification. They are used to explain the technical solutions of the present invention together with the specific embodiments of the present application, and do not limit the technical solutions of the present invention.

FIG. 1 is a hydrogen nuclear magnetic resonance spectrum ( ¹ H NMR) diagram of Example 1. FIG.

FIG. 2 is an infrared spectrogram of Example 1. FIG.

Figure 3 is the surface tension of Example 1 and the silicone defoamer (tego931) added to the unsaturated resin.

Figure 4 shows the effect of Example 1 on the curing speed of the unsaturated resin.

Figure 5 shows the mechanical properties of the unsaturated resin-calcium carbonate system added in Example 1.

FIG. 6 is a graph of gel permeation chromatography (GPC) of Example 1. FIG.

FIG. 7 is an infrared spectrogram of Example 2. FIG.

Figure 8 shows the surface tension of Example 2 and the addition of a silicone defoamer (Tego 931) to an unsaturated resin.

Figure 9 shows the effect of the dispersant of Example 2 on the curing speed of the unsaturated resin.

Figure 10 shows the mechanical properties of the unsaturated resin-calcium carbonate system added in Example 2.

FIG. 11 is an infrared spectrogram of Example 3. FIG.

Figure 12 shows the mechanical properties of the unsaturated resin-calcium carbonate system of Example 3 added.

Detailed ways

The present invention will be described in more detail below with reference to the accompanying drawings, in which preferred embodiments of the invention are shown, it should be understood that those skilled in the art can modify the invention described herein and still achieve the beneficial effects of the invention. Therefore, the following description should be construed as widely known to those skilled in the art and not as a limitation of the present invention.

In order to make the objects and features of the present invention more clearly understood, the specific embodiments of the present invention will be further described below with reference to the accompanying drawings. It should be noted that, the accompanying drawings are all in a very simplified form and use inaccurate ratios, and are only used for the purpose of assisting in explaining the embodiments of the present invention conveniently and clearly.

The present invention will be further described below in conjunction with specific embodiments.

Example 1

A kind of synthetic method of wetting and defoaming auxiliary agent, comprises the following steps:

S1: Under high-purity argon atmosphere, place 0.0201g (0.25mmol) 1,2-propanediol, 22.85g (0.20mol) ε-caprolactone and 2.0mg (0.005mmol) stannous octoate in the reactor, React at 100°C for 36 hours to obtain polycaprolactone with hydroxyl groups at both ends of the molecule;

S2: Add 69g solvent 1,4-dioxane to the product of step S1, stir to dissolve it, add 0.098g (1.0mmol) maleic anhydride, add 6.0mg (0.05mmol) 4-dimethylaminopyridine and 10 ℃, the reaction was carried out for 24 hours. The obtained reaction solution was precipitated in 3450g precipitating agent (petroleum ether and anhydrous ether were mixed according to mass ratio 1:4) in batches, and the solid product was collected and dried to constant weight in a vacuum oven;

S3: The product obtained in step 2 was dissolved in 69 g of tetrahydrofuran, 80 mg (0.75 mmol) of 3-mercaptopropionic acid and 4 mg of azobisisobutyronitrile were added, and the reaction was carried out at 60° C. for 6 hours. After the completion of the reaction, the reaction product was subjected to a rotary evaporator to remove part of the solvent, and then precipitated in 3450 g of precipitating agent (petroleum ether and anhydrous ether were mixed in a mass ratio of 1:4) in batches, and the solid product was collected and placed in a vacuum oven. After neutralization to constant weight, polycarboxypolycaprolactone is obtained.

The structure of polycarboxypolycaprolactone was characterized by hydrogen nuclear magnetic resonance ( ¹ HNMR) and infrared spectroscopy, respectively (the results are shown in Figures 1 and 2). As shown in Figure 1, at the chemical shift of 4.05ppm, it is the absorption peak of the hydrogen proton on the methylene group connected to the ether bond after caprolactone ring-opening, where the integral area of hydrogen is 1.0, and at the chemical shift of 2.31ppm, it is the absorption peak of the hydrogen proton on the methylene group connected to the ether bond. The absorption peak of the hydrogen proton on the connected methylene group, where the integral area of hydrogen is 1.01, the absorption peaks at 1.65 and 1.39 ppm are the absorption peaks of the methylene group after caprolactone ring-opening, respectively, corresponding to the hydrogen proton The integral area is 1.99 and 1.02. From the chemical shift and integral area, it can be confirmed that the caprolactone undergoes a successful ring-opening reaction, resulting in a high molecular weight polymer. It can be seen from Figure 2 that the absorption peak of the carbonyl group at the end of the polycaprolactone molecular chain appears at 3542cm ^-1 , and the in-plane bending vibration of OH in the carbonyl dimer and the stretching vibration of CO in the carboxyl group appear at 1411cm ^-1 . The coupling absorption peak of . Combining the 1H NMR and IR spectra of the product, it can be proved that the target product has been successfully prepared.

Example 1 was diluted with tetrahydrofuran to a solution with a mass concentration of 30% (the content of the final product of Example 1 in the solution was 30%). Figure 3 is the surface tension of the solution of Example 1 and a typical silicone defoamer (tego931) added to the unsaturated resin (trade name: 191#) in different amounts. As shown in the figure, the surface tension of the unsaturated resin added with tego931 is in the range of 25-21mN/m (as the dosage increases, the surface tension decreases slightly), indicating that tego931 is defoaming by reducing the surface tension of the matrix resin. When Example 1 is added to the unsaturated resin, its surface tension is stable at about 35mN/m (basically equal to the surface tension of the unsaturated resin without additives), illustrating the defoaming mechanism of Example 1 and tego931 Different, that is, it does not exert the defoaming function by reducing the surface tension of the matrix resin. Combined with the experimental results of Figure 5, because the addition of the polycarboxy polycaprolactone of the present invention does not affect the surface tension of the unsaturated resin, the addition of the polycarboxylate polycaprolactone of the present invention. Carboxy polycaprolactone does not affect the mechanical properties of the unsaturated resin-inorganic filler cured material like the commonly used silicone defoamer (tego931).

Add 0.0%-0.5% of the tetrahydrofuran solution of the above-mentioned Example 1 with different qualities (the concentration of the final product of Example 1 in the solution is 30%) and the calcium carbonate of 20% of the resin quality ( 325 mesh), add cobalt naphthenate catalyst of 2% by mass of resin and methyl ethyl ketone peroxide curing agent of 2% by mass of resin, and test the curing time of unsaturated resin, as shown in Figure 4. When the addition amount is less than or equal to 0.4%, the curing time of the unsaturated resin-calcium carbonate system is all about 1950 seconds. When the addition amount increases to 0.5%, the curing time of the unsaturated resin-calcium carbonate system decreases slightly to 1873 seconds. , indicating that the addition of Example 1 did not reduce the curing reaction speed of the unsaturated resin-calcium carbonate system.

Mix 18g unsaturated resin (brand name is 191#), 2g calcium carbonate (325 mesh) and 80g quartz sand, add 0.0%-0.5% tetrahydrofuran solution of the above-mentioned embodiment 1 of different quality (the final product of Example 1 in the solution) respectively. Concentration of 30%) and tego931 (control group) were mixed uniformly, and then the above mixture was cured in a mold of a specific size with a cobalt naphthenate catalyst with a resin mass of 2% and a methyl ethyl ketone peroxide curing agent with a resin mass of 2%. After the splines were completely cured, they were cured at room temperature for a week, and the compressive properties of the cured materials were measured on a universal testing machine. The results are shown in Figure 5.

As shown in Figure 5, the compressive strength of the sample without the additive of the present invention is 53.81MPa, and when the addition amount of the defoamer tego931 is 0.3%, the compressive performance of the sample reaches the maximum value of 55.74MPa (about 2MPa higher than the blank value). , the addition amount is less than 0.3% or more than 0.4%, and its compressive performance is lower than that of the blank sample, indicating that in the spline added with tego931, the two effects of degassing and reducing the interface strength of inorganic filler and resin coexist. When the content of tego931 When it is higher, reducing the interfacial strength between the resin and the inorganic filler plays a major role, and the addition of the silicone defoamer weakens the interfacial strength between the resin and the inorganic filler particles, resulting in a decrease in the compressive performance. For the product of Example 1, in all the investigated concentration ranges (0.2%-0.5%), adding the wetting and defoaming agent of the present invention can improve the compression resistance of the cured material, and the current addition amount is 0.4% When , the mechanical properties of the cured material reached the maximum value of 58.19MPa, indicating that the addition of Example 1 improved the interface properties between the unsaturated resin and the inorganic filler. After most of the bubbles were removed, the number of defect points in the cured material was reduced. Therefore, Will improve the compressive properties of the cured material.

According to Scott's theory, whether phase separation occurs in the system is related to the molecular weight of the polymer. The higher the molecular weight of the polymer, the easier it is to phase separate from the unsaturated resin, which is less conducive to the stable suspension of bubbles in the system. Fig. 6 is the gel permeation chromatography (GPC) figure of embodiment 1, it can be seen that the number-average molecular weight of the product of the present invention is about 83400 g/mol, and its molecular weight distribution is 1.57, indicating that the product is a high molecular polymer, which is easy to be mixed with unsaturated The phase separation of the resin is not conducive to the stable suspension of bubbles in the system. When the polycarboxy polycaprolactone of the present invention is used as a wetting and defoaming agent, a plurality of carboxyl groups are firmly adsorbed on the surface of the inorganic particles, so that the linear molecular chains are bent, and the bent polycaprolactone molecular chains are under the thermal motion of the molecules. Easily drive air bubbles out of unsaturated resins.

And, the above conclusion is further proved by the wetting and defoaming effect of the following examples.

Embodiment 2

A kind of synthetic method of wetting and defoaming auxiliary agent, comprises the following steps:

S1: Under a high-purity nitrogen atmosphere, 0.2011 g (0.10 mmol) polyethylene glycol (average molecular weight is 2000 g/mol), 11.41 g (0.10 mol) ε-caprolactone and 81.3 mg (0.20 mmol) stannous octoate were mixed placed in a reactor, and reacted at 130 ° C for 24 hours to obtain polycaprolactone with hydroxyl groups at both ends of the molecule;

S2: Add 114g solvent chloroform to the product of step S1, stir to dissolve, add 0.098g (1.0mmol) maleic anhydride, and react 72g under 12.7mg (0.10mmol) 4-dimethylaminopyridine and 40°C Hour. The obtained reaction solution was precipitated in batches of 5700 g of precipitating agent (ethanol and methanol were mixed in a mass ratio of 1:2), and the solid product was collected and dried to constant weight in a vacuum oven;

S3: Dissolve the product obtained in step 2 with 114 g of 1,4-dioxane, add 107 mg (1.0 mmol) of 3-mercaptopropionic acid and 53 mg of azobisisoheptanenitrile, and react at 90° C. for 48 hours. After the reaction, after the reaction product was removed from the solvent with a rotary evaporator, it was precipitated in 5700 g of precipitating agent (petroleum ether and anhydrous ether were mixed in a mass ratio of 1:5) in batches, and the solid product was collected and placed in a vacuum oven. After medium to constant weight, a high molecular weight polycarboxy polycaprolactone is obtained.

The structure of polycarboxypolycaprolactone was characterized by infrared spectroscopy (the results are shown in Fig. 7). It can be seen from Figure 7 that the absorption peak of the carbonyl group at the end of the polycaprolactone molecular chain appears at 3537 cm ^-1 , and the absorption peaks of alkanes in the main chain of polycaprolactone at 2944 and 2866 cm ^-1 are at 1731 cm ^-1 . The strong peak of is the absorption peak of the carbonyl group, and the coupling absorption peak of the in-plane bending vibration of OH in the carbonyl dimer and the stretching vibration of CO in the carboxyl group appeared at 1413 cm ^-1 . The above information can prove that the target product was successfully prepared.

Example 2 was diluted with tetrahydrofuran to a solution with a mass concentration of 30%. Figure 8 is the surface tension measured by the static contact angle method after adding different amounts of the solution of Example 2 and tego931 to the unsaturated resin (grade 191#). As shown in the figure, the surface tension of the unsaturated resin added with tego931 is in the range of 25-21mN/m, and as the amount of addition increases, the surface tension decreases slightly, indicating that tego931 is achieved by reducing the surface tension of the matrix resin. The surface tension of Example 2 added to the unsaturated resin is stable in the range of 35-36 mN/m, indicating that the addition of Example 2 will not affect the surface tension of the unsaturated resin.

In the unsaturated resin (191#), add the tetrahydrofuran solution of Example 2 with different quality (wherein, the concentration of the product of Example 2 in the solution is 30%) and the calcium carbonate (325 mesh) of 20% resin quality, resin quality 1 % cobalt naphthenate catalyst and resin mass 2% methyl ethyl ketone peroxide curing agent, the curing time of the tested unsaturated resin is shown in Figure 9. Figure 9 shows that the curing reaction time of the unsaturated resin-calcium carbonate is gradually shortened when the addition amount increases from 0.2% to 0.5% (from 4378 seconds for the blank sample to 3719 seconds). The reason for the analysis is that the molecular weight of Example 2 is relatively large (102kg/mol), and as a wetting and defoaming aid, it has a very fast anchoring speed and exhausting speed (wet the surface of calcium carbonate in a short time, and the air on the surface of calcium carbonate is removed. and the rapid air discharge system introduced by stirring), eliminating the polymerization inhibition effect of oxygen in the air on the curing reaction of the unsaturated resin, so the wetting and degassing effect of Example 2 can significantly shorten the curing of the unsaturated resin-calcium carbonate system. Reaction time.

20g unsaturated resin (191#), 2g calcium carbonate (325 mesh) and 78g quartz sand are mixed, respectively, add the tetrahydrofuran solution of 0.2%-0.5% different quality Example 2 (wherein, the concentration of the product of Example 2 in the solution) 30%) and tego931 (control group) were mixed uniformly, and then the above mixture was cured in a mold of specific size with 1% by mass of resin cobalt naphthenate catalyst and 2% by mass of resin of methyl ethyl ketone peroxide curing agent. After the splines were completely cured, they were cured at room temperature for a week, and the compressive properties of the cured materials were measured on a universal testing machine. The results are shown in Figure 10.

As shown in Figure 10, the compressive strength of the sample without additives was 48.97MPa. Combined with the results in Figure 5, it was demonstrated that increasing the amount of unsaturated resin and decreasing the amount of filler would reduce the mechanical properties of the cured system. It can also be seen from Figure 10 that when the addition amount of defoamer tego931 is small (<0.3%), the compressive performance of the spline increases slightly, and the compressive performance of the cured sample with the addition amount greater than 0.3% gradually decreases with the increase of the addition amount. , indicating that when the content of tego931 is high, silicone plays a major role in reducing the interface strength between resin and inorganic filler, and silicone weakens the interface strength between resin and inorganic filler particles, resulting in a decrease in compressive performance. For the product of Example 2, in all the investigated concentration ranges (0.2%-0.5%), with the increase of the amount of wetting and defoaming agent added, the compression resistance of the cured material gradually increased, indicating that the The addition improves the interface properties of the unsaturated resin and the inorganic filler, and prolonging the curing time is beneficial to reduce the number of air bubbles in the cured material, so the performance of the cured material is significantly improved.

Embodiment 3

A kind of synthetic method of wetting and defoaming auxiliary agent, comprises the following steps:

S1: Under an argon atmosphere, 0.1067g (0.10mmol) of diethylene glycol, 9.131g (80mmol) of ε-caprolactone and 40.7mg (0.10mmol) of stannous octoate were placed in a reactor, at 120 Reaction at °C for 72 hours to obtain polycaprolactone with hydroxyl groups at both ends of the molecule;

S2: add 46g solvent N,N-dimethylformamide to the product of step S1, stir to dissolve, add 50mg (0.5mmol) maleic anhydride, add 12.7mg (0.10mmol) 4-dimethylaminopyridine and 30 ℃, the reaction was carried out for 36 hours. The obtained reaction solution was precipitated in batches of 4600 g of precipitating agent (ethanol and methanol were mixed in a mass ratio of 1:10), and the solid product was collected and dried to constant weight in a vacuum oven;

S3: The product obtained in step 2 was dissolved with 92 g of 1,4-dioxane, 54 mg (0.5 mmol) of 3-mercaptopropionic acid and 17 mg of azobisisoheptonitrile were added, and the reaction was carried out at 80° C. for 36 hours. After the reaction, after removing most of the solvent with a rotary evaporator, the reaction product was precipitated in 4600 g of precipitating agent (petroleum ether and anhydrous ether were mixed in a mass ratio of 1:9) in batches, and the solid product was collected and placed in After being kept in a vacuum oven to a constant weight, a high molecular weight polycarboxy polycaprolactone is obtained.

The structure of polycarboxypolycaprolactone was characterized by infrared spectroscopy (the results are shown in Figure 11). It can be seen from Figure 11 that the absorption peak of the carbonyl group at the end of the polycaprolactone molecular chain appears at 3542 cm ^-1 , the absorption peaks of alkanes in the main chain of polycaprolactone at 2946 and 2869 cm ^-1 , and the absorption peak at 1734 cm ^-1 The strong peak of is the absorption peak of the carbonyl group, and the coupling absorption peaks of the in-plane bending vibration of OH in the carbonyl dimer and the stretching vibration of CO in the carboxyl group appear at 1410 cm ^-1 . The above information can prove that the target product was successfully prepared.

20g unsaturated resin (trade name is 196#), 2g calcium carbonate (325 mesh) and 78g quartz sand are mixed, respectively add the tetrahydrofuran solution of 0.2%-0.5% different quality Example 3 (wherein, in the solution, Example 2 The concentration of the product is 30%) and tego931 (control group) are mixed uniformly, and then the above mixture is carried out in a mold of a specific size with a cobalt naphthenate catalyst with a resin mass of 2% and a methyl ethyl ketone peroxide curing agent with a resin mass of 2%. cured. After the splines were completely cured, they were cured at room temperature for a week, and the compressive properties of the cured materials were measured on a universal testing machine. The results are shown in Figure 12.

As shown in Figure 12, the compressive strength of the sample without additives was 42.66 MPa. When the addition amount of defoamer tego931 was 0.2%, the compressive properties of the splines reached the maximum value of 43.4 MPa (about 0.74 MPa higher than the blank value). Continuing to increase the addition of tego931, the compressive properties of the splines gradually decreased, indicating that when the content of tego931 was high, the addition of silicone defoamer weakened the interface strength between resin and inorganic filler particles. For the product of Example 3, the addition of a wetting and defoaming agent can improve the compression resistance of the cured material in all the examined concentration ranges (0.2%-0.5%). When the addition amount in the current period is 0.5%, the mechanical properties of the cured material reach the maximum value of 47.63MPa (about 4.97MPa higher than the blank value), indicating that the addition of Example 3 improves the interface properties between the unsaturated resin and calcium carbonate particles, and removes the large Part of the air bubbles, so it will improve the compressive properties of the cured material.

In the present invention, diol, ε-caprolactone and stannous octoate are placed in a reactor protected by high-purity nitrogen or high-purity argon, and reacted at 100-130 DEG C for 24-72 hours to obtain hydroxyl polycaprolactone; At 4-dimethylaminopyridine and 10-40 ℃, hydroxypolycaprolactone and maleic anhydride are esterified in solution; under the action of initiator, the product is reacted with 3-mercaptopropionic acid to obtain polycaprolactone containing Carboxylic polycaprolactone. The above examples show that the present invention controls the molecular weight of the product to be as high as 80-100 kg/mol from the principle of defoaming/defoaming to obtain a defoaming agent suitable for the unsaturated resin-inorganic filler particle composite system. In addition, the polycarboxylated polycaprolactone auxiliary agent of the present invention has obvious effects on reducing the content of air bubbles in the system and improving the mechanical properties of the cured material.

Moreover, the synthesis method of the invention is simple, the synthesized high-molecular-weight polycaprolactone has high surface tension, and has both functions of wetting and defoaming, so that the air bubbles can be removed during the dispersion process of the inorganic filler, and the air bubbles can be effectively prevented from stably existing in the In the system, and the mechanical properties of the curing system of the unsaturated resin are guaranteed to remain unchanged.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. 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.

Although the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, they do not limit the scope of protection of the present invention. Those skilled in the art should understand that on the basis of the technical solutions of the present invention, those skilled in the art do not need to pay creative efforts. Various modifications or deformations that can be made are still within the protection scope of the present invention.

Claims (5)

1. A wetting defoaming auxiliary agent is characterized in that the structural general formula is (I) or (II):

wherein n is a positive integer, and n is more than or equal to 400 and less than or equal to 500;

r is selected from

Wherein m, o and p are positive integers.

2. A synthesis method of a wetting defoaming auxiliary agent is characterized by comprising the following steps:

s1: placing dihydric alcohol, epsilon-caprolactone and stannous octoate in a reactor under inert atmosphere, and reacting for 24-72 hours at the temperature of 100 ℃ and 130 ℃ to obtain polycaprolactone with two hydroxyl groups at two molecular ends;

s2: dissolving polycaprolactone with two hydroxyl groups at two molecular ends obtained in the step S1 in a solvent, adding maleic anhydride, reacting for 24-72 hours at 10-40 ℃ in 4-dimethylaminopyridine until the reaction is finished to obtain a solution to be precipitated,

precipitating the obtained solution to be precipitated in a precipitating agent, collecting solid precipitates, and drying the solid precipitates in a vacuum oven to constant weight to obtain a product;

s3: dissolving the product obtained in the step 2 by using a solvent, adding 3-mercaptopropionic acid and an initiator, reacting for 6-48 hours at the temperature of 60-90 ℃ until the reaction is finished,

after the reaction is finished, removing the solvent from the reaction product by using a rotary evaporator to obtain a solution to be precipitated, precipitating the solution to be precipitated in a precipitator, collecting solid precipitate, and putting the solid precipitate in a vacuum oven to constant weight to obtain the polycarboxy polycaprolactone;

wherein,

the dihydric alcohol is any one or a mixture of more of 1, 2-ethanediol, 1, 2-propanediol, 1, 4-butanediol, 2-methyl-1, 3-propanediol, 1, 5-pentanediol, 2-methyl-1, 4-butanediol, 1, 6-hexanol, 3, 6-octanediol, 1, 8-octanediol, 1, 4-p-phenylenediethanol, 1, 4-p-phenylenedibutanol, 2,3,5, 6-tetrafluoro-p-xylylene glycol, 1, 4-cyclohexyl-diethanol, polyethylene glycol, polypropylene glycol, polyethylene glycol-co-polypropylene glycol and polytetrahydrofuran diol;

the solvent is any one or a mixture of more of 1, 4-dioxane, tetrahydrofuran, N-dimethylformamide and trichloromethane;

the initiator is any one or a mixture of azodiisobutyronitrile, azodiisoheptonitrile, azodicyano valeric acid, azodiisobutyronitrile dimethyl ester and 2,2' -azobis (4-methoxy-2, 4-dimethyl valeronitrile);

the precipitator is a mixture of diethyl ether and petroleum ether, or a mixture of methanol and ethanol;

and,

the molar ratio of the dihydric alcohol, the epsilon-caprolactone, the stannous octoate, the maleic anhydride, the 4-dimethylamino pyridine and the 3-mercaptopropionic acid is 1 (800) -1000 (0.02-2) (4-10) to (0.2-1) to (3-10);

the addition mass of the initiator is 5-50% of the mass of the 3-mercaptopropionic acid.

3. The method according to claim 2, wherein the mass ratio of the precipitant petroleum ether to diethyl ether is 1: 1-100, the mass ratio of the precipitant ethanol to methanol is 1: 1-100, and the mass ratio of the solution to be precipitated in step S2 or S3 to the precipitant is 1: 50-200.

4. The method of claim 2, wherein the inert gas is helium or nitrogen.

5. The use of the wet defoamation assistant of claim 1 as a wet defoamation assistant for an unsaturated resin-inorganic filler system.

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