Non-ionic alkynol modified polysiloxane as well as preparation method and application thereof

Abstract

The invention provides nonionic alkynol modified polysiloxane. The nonionic alkynol modified polysiloxane comprises a structure as shown in a formula (I). Compared with the prior art, the alkynol modified polysiloxane provided by the invention has low surface tension, low foam performance and efficient wetting ability, is simple in process preparation and free of subsequent treatment process, also effectively solves the problems of rapid heat release and the like in the reaction process, and is suitable for safe and efficient industrial production. # imgabs0 #

Description

Technical Field

[0001] The invention belongs to the technical field of coating additives, and in particular relates to a nonionic acetylenic alcohol modified polysiloxane, a preparation method and application thereof. Background Art

[0002] Compared with organic coatings, water-based coatings are safer and more environmentally friendly. However, due to their high surface tension, surfactants have to be used to reduce the surface tension of the system so that water-based coatings can achieve the desired coating effect. Traditional surfactants usually produce severe foam, so the selection of defoamers becomes a very troublesome matter. Because the addition of defoamers not only affects the wetting properties of the system, but sometimes also causes adverse effects such as shrinkage, so it is usually difficult for coating formulators to find a balance between wetting and foaming.

[0003] Defoaming wetting agents can not only reduce the surface tension of the entire system, making it have good substrate wettability, but also improve the defoaming performance to a certain extent, eliminate foam in the coating mixing production process, and effectively prevent shrinkage holes, so they can be widely used in downstream coating and ink spraying, PVC board cleaning, metal cutting and other fields.

[0004] Chinese patent publication number CN101434615A discloses a polyether-modified silicone oil surfactant with extremely low surface tension, which is obtained by hydrosilylation of allyl polyether and methyl hydrogen silicone oil, but has the disadvantage of generating a lot of foam; Chinese patent publication number CN101653708A discloses a silane surfactant connected by covalent bonds, but its process steps are complicated, using a traditional kettle reaction method and involving subsequent treatment processes such as distilling off low-boiling components, and its preparation process is complicated, which is not conducive to industrial scale-up production. Summary of the invention

[0005] In view of this, the technical problem to be solved by the present invention is to provide a nonionic acetylenic alcohol-modified polysiloxane that can be used as a defoaming wetting agent, and a preparation method and application thereof.

[0006] The present invention provides a nonionic acetylenic alcohol modified polysiloxane, comprising a structure shown in formula (I):

[0007]

[0008] Here, x is an integer of 0 to 5, y is an integer of 1 to 5, m and n are each independently an integer of 0 to 10, and R is a hydroxyl group or a C1 to C10 alkoxy group.

[0009] Preferably, R is hydroxy or methoxy.

[0010] The present invention also provides a method for preparing a nonionic acetylenic alcohol modified polysiloxane, comprising the following steps:

[0011] S1) mixing hexamethyldisiloxane, D4H cyclotetrasiloxane and octamethylcyclotetrasiloxane, adding an acidic catalyst, and performing a ring-opening polymerization reaction to obtain a hydrogen-containing polysiloxane;

[0012] S2) mixing the hydrogen-containing polysiloxane with a platinum-containing catalyst to obtain component A; introducing component A and butynediol polyoxyethylene ether represented by formula (II) into a microchannel reactor for hydrosilylation reaction to obtain a nonionic acetylenic alcohol-modified polysiloxane represented by formula (I);

[0013]

[0014] Here, x is an integer of 0 to 5, y is an integer of 1 to 5, m and n are each independently an integer of 0 to 10, and R is a hydroxyl group or a C1 to C10 alkoxy group.

[0015] Preferably, the acidic catalyst is selected from acidic resins;

[0016] The mass of the acidic catalyst is 1% to 8% of the total mass of hexamethyldisiloxane, D4H cyclotetrasiloxane and octamethylcyclotetrasiloxane.

[0017] Preferably, the molar ratio of the butynediol polyoxyethylene ether represented by formula (II) to the hydrogen-containing polysiloxane is 1 to 1.5:1.

[0018] Preferably, the platinum-containing catalyst in step S2) is selected from Speier catalyst and / or Karstedt catalyst;

[0019] The mass ratio of the total mass of the butynediol polyoxyethylene ether represented by the formula (II) and the hydrogen-containing polysiloxane to the mass ratio of the platinum element in the platinum-containing catalyst is 1 g: 1 to 50 μg.

[0020] Preferably, the total mass flow rate of component A in step S2) and the butine diol polyoxyethylene ether represented by formula (II) in the microchannel reactor is 20 to 120 g / min.

[0021] Preferably, the temperature of the ring-opening polymerization reaction in step S1) is 40 to 100° C.; the time of the ring-opening polymerization reaction is 3 to 8 hours;

[0022] The temperature of the hydrosilylation reaction in step S2) is 60-125°C.

[0023] The present invention also provides a use of the nonionic acetylenic alcohol modified polysiloxane as a defoaming wetting agent.

[0024] The present invention provides a nonionic acetylene alcohol modified polysiloxane, comprising a structure shown in formula (I). Compared with the prior art, the acetylene alcohol modified polysiloxane provided by the present invention has low surface tension, low foaming performance and high wetting ability, and its preparation process is simple, without subsequent treatment process, and also effectively solves the problem of rapid heat release during the reaction process, and is suitable for safe and efficient industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a photographic comparison of the acetylene alcohol-modified polysiloxane obtained in Example 2 of the present invention and the acetylene alcohol-modified polysiloxane obtained in Comparative Example 1;

[0026] Figure 2 is the hydrogen nuclear magnetic resonance spectrum of the acetylenic alcohol-modified polysiloxane obtained in Example 1 of the present invention;

[0027] Figure 3 is the hydrogen nuclear magnetic resonance spectrum of the acetylenic alcohol-modified polysiloxane obtained in Example 2 of the present invention;

[0028] Figure 4 The graph is a heat release curve during the reaction of heptamethyltrisiloxane and butynediol polyoxyethylene ether of the present invention. DETAILED DESCRIPTION

[0029] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0030] The present invention provides a nonionic acetylenic alcohol modified polysiloxane, comprising a structure shown in formula (I):

[0031]

[0032] wherein x is an integer of 0 to 5, preferably an integer of 1 to 4, more preferably an integer of 1 to 3, and more preferably 1 or 2; y is an integer of 1 to 5, preferably an integer of 2 to 5, more preferably an integer of 2 to 4, and more preferably 2 or 3; m and n are each independently an integer of 0 to 10, more preferably each independently an integer of 1 to 9, more preferably each independently an integer of 1 to 8, more preferably each independently an integer of 1 to 6, more preferably each independently an integer of 1 to 5, and more preferably each independently an integer of 1 to 5. R is independently an integer of 1 to 4, preferably each independently an integer of 1 to 3, most preferably each independently 1 or 2; R is hydroxy or C1 to C10 alkoxy, preferably hydroxy or C1 to C8 alkoxy, more preferably hydroxy or C1 to C6 alkoxy, still more preferably hydroxy or C1 to C5 alkoxy, still more preferably hydroxy or C1 to C4 alkoxy, still more preferably hydroxy or C1 to C3 alkoxy, still more preferably hydroxy or C1 to C2 alkoxy, most preferably hydroxy or methoxy.

[0033] The acetylene alcohol modified polysiloxane provided by the present invention has low surface tension, low foaming performance and high-efficiency wetting ability, and its preparation process is simple, without subsequent treatment process, and also effectively solves the problem of rapid heat release during the reaction process, and is suitable for safe and efficient industrial production.

[0034] The present invention also provides a method for preparing a nonionic acetylene alcohol modified polysiloxane, comprising the following steps: S1) mixing hexamethyldisiloxane, D4H cyclotetrasiloxane and octamethylcyclotetrasiloxane, adding an acidic catalyst, and performing a ring-opening polymerization reaction to obtain a hydrogen-containing polysiloxane; S2) mixing the hydrogen-containing polysiloxane with a platinum-containing catalyst to obtain a component A; introducing the component A and a butynediol polyoxyethylene ether represented by formula (II) into a microchannel reactor to perform a hydrosilylation reaction to obtain a nonionic acetylene alcohol modified polysiloxane represented by formula (I);

[0035]

[0036] Here, x is an integer of 0 to 5, y is an integer of 1 to 5, m and n are each independently an integer of 0 to 10, and R is a hydroxyl group or a C1 to C10 alkoxy group.

[0037] The present invention has no particular limitation on the sources of all raw materials, and any raw materials available on the market can be used; the x, y, z, m, n and R are the same as those described above and will not be described in detail herein.

[0038] Hexamethyldisiloxane, D4H cyclotetrasiloxane and octamethylcyclotetrasiloxane are mixed, an acidic catalyst is added, and a ring-opening polymerization reaction is carried out; in the present invention, the hexamethyldisiloxane, D4H cyclotetrasiloxane and octamethylcyclotetrasiloxane are preferably mixed uniformly in a protective atmosphere; the protective atmosphere can be a protective atmosphere well known to those skilled in the art, and there is no special limitation, and nitrogen is preferably used in the present invention; the acidic catalyst is preferably a solid acid catalyst, more preferably an acidic resin, and more preferably a strongly acidic resin; in the embodiment provided by the present invention, HND-582 solid acid catalyst is specifically used The agent is used as an example for explanation; the mass of the acidic catalyst is preferably 1% to 8% of the total mass of hexamethyldisiloxane, D4Hcyclotetrasiloxane and octamethylcyclotetrasiloxane, more preferably 2% to 8%, more preferably 2% to 6%, more preferably 2% to 4%, and most preferably 2% to 3%; the temperature of the ring-opening polymerization reaction is preferably 40 to 100°C, more preferably 50 to 90°C, more preferably 60 to 80°C, and most preferably 60 to 70°C; the time of the ring-opening polymerization reaction is preferably 3 to 8h, more preferably 4 to 8h, more preferably 5 to 7h, and most preferably 5 to 6h.

[0039] After the ring-opening polymerization reaction, the low-boiling point components are preferably removed under negative pressure and heating conditions to obtain hydrogen-containing polysiloxane; the negative pressure is preferably -0.05 to -0.1 MPa, more preferably -0.08 to -0.1 MPa, more preferably -0.09 to -0.1 MPa, and most preferably -0.095 MPa; the heating temperature is preferably 80 to 120° C., more preferably 90 to 110° C., and more preferably 100° C.; the heating time is 30 to 90 min, more preferably 40 to 80 min, more preferably 50 to 70 min, and most preferably 60 min.

[0040] The hydrogen-containing polysiloxane is mixed with a platinum-containing catalyst to obtain component A; the platinum-containing catalyst can be a platinum-containing catalyst well known to those skilled in the art without any special limitation, and is preferably a Speier catalyst and / or a Karstedt catalyst in the present invention.

[0041] The component A and the butynediol polyoxyethylene ether shown in formula (II) are introduced into a microchannel reactor for a hydrosilylation reaction; the molar ratio of the butynediol polyoxyethylene ether shown in formula (II) to the hydrogen-containing polysiloxane is preferably 1-1.5:1, more preferably 1-1.2:1; the mass ratio of the total mass of the butynediol polyoxyethylene ether shown in formula (II) and the hydrogen-containing polysiloxane to the mass of the platinum element in the platinum-containing catalyst is preferably 1g:1-50μg, more preferably 1g:5-40μg, more preferably 1g:10-30μg, more preferably 1g:10-20μg, and most preferably 1g:10-15μg; the total mass flow rate of the component A and the butynediol polyoxyethylene ether shown in formula (II) in the microchannel reactor is preferably 20-120g / min, more preferably 30-110g / min, and then Preferably, it is 40-100 g / min, and most preferably, it is 40-80 g / min; the mass flow rate ratio of the component A to the butine diol polyoxyethylene ether represented by formula (II) in the microchannel reactor is preferably 1:1-1.5, more preferably 1:1.1-1.4, and further preferably 1:1.2-1.35; the temperature of the hydrosilylation reaction is preferably 60-125°C, more preferably 80-120°C, further preferably 90-120°C, and most preferably 100-110°C; in the present invention, it is preferred that the component A and the butine diol polyoxyethylene ether represented by formula (II) are introduced after the microchannel reactor reaches the temperature of the hydrosilylation reaction; the time of the hydrosilylation reaction is preferably 5-30 min, more preferably 10-25 min, further preferably 15-25 min, and most preferably 15-20 min.

[0042] In a specific embodiment provided by the present invention, the nonionic acetylenic alcohol-modified polysiloxane is reacted according to the following reaction formula:

[0043]

[0044]

[0045] Microchannel reactor utilizes its refinement characteristics, so that the heat transfer and mass transfer performance of fluid are greatly improved compared with traditional reactors, that is, system miniaturization can achieve the goal of chemical process intensification. And it is essentially a pipeline reactor of continuous flow, compared with the traditional kettle reactor commonly used on the market, the tubular reactor can omit a long dropping time because it can react quickly and continuously, improve production efficiency, and can avoid the rapid heat release and even the material rushing problem in the reaction process, safe and controllable, and can be batched for pilot production. In addition, the alkynol-modified polysiloxane prepared by the microchannel reactor of the present invention does not need to be evaporated to remove solvent and low-boiling components, nor does it need to be decolorized, with few by-products, streamlined process flow, and improved product purity. Moreover, the whole reaction process does not use any toxic solvent, without the generation of any waste gas and waste water, and is very environmentally friendly.

[0046] The present invention also provides a use of the nonionic acetylenic alcohol modified polysiloxane as a defoaming wetting agent.

[0047] In order to further illustrate the present invention, a nonionic acetylenic alcohol modified polysiloxane provided by the present invention, a preparation method thereof and application thereof are described in detail below in conjunction with examples.

[0048] The reagents used in the following examples are all commercially available; the microchannel reactor used in the examples is a microchannel G1 glass reactor produced by Corning Reactor Technology Co., Ltd.

[0049] Example 1

[0050] 1.1 Preparation of hydrogen-containing polysiloxane:

[0051] A 250 ml four-necked flask was thoroughly dried and nitrogen was passed through for 10 min. 32.4 g of hexamethyldisiloxane and 36 g of hydrogen-containing tetramethylcyclotetrasiloxane (D4 H ) and 29.6g octamethylcyclotetrasiloxane were placed in a four-necked flask, and then 2g of strong acid resin (HND-582) was added as a catalyst, the temperature was raised to 60°C, and the reaction was carried out for 5h. Finally, under negative pressure conditions (vacuum gauge pressure was -0.095MPa), the low boiling point components were removed at 100°C for 60min to obtain the following transparent intermediate, which was hydrogen-containing polysiloxane.

[0052]

[0053] 1.2 Preparation of acetylenic alcohol modified polysiloxane:

[0054] 500 g of hydrogenated polysiloxane and Karstedt catalyst were added to storage tank 1 and mixed evenly to obtain component A; 639 g of butynediol polydioxyethylene ether was added to storage tank 2 as component B (m and n were both 1, and R was -OH); the molar ratio of the butynediol polydioxyethylene ether to the hydrogenated polysiloxane was 1.2:1, and the mass ratio of the total mass of the butynediol polydioxyethylene ether and the hydrogenated polysiloxane to the platinum element in the platinum-containing catalyst was 1 g:10 μg; the temperature of the microchannel reactor was set at 100° C., and after the temperature was stabilized, the mass flow rate of component A was adjusted to 30 g / min, and the mass flow rate of component B was adjusted to 40 g / min, and components A and B were transported to the reaction plate of the microchannel reactor for hydrosilylation reaction; the product was received in the product tank, and after reacting for 20 minutes, an amber product acetylenol-modified polysiloxane was obtained.

[0055]

[0056] Example 2

[0057] 2.1 Preparation of hydrogen-containing polysiloxane:

[0058] A 250 ml four-necked flask was thoroughly dried and nitrogen was passed through for 10 min. 48.6 g of hexamethyldisiloxane and 36 g of hydrogen-containing tetramethylcyclotetrasiloxane (D4 H ) and 22.2g of octamethylcyclotetrasiloxane were placed in a four-necked flask, and then 4.5g of strong acid resin (HND-582) was added as a catalyst, the temperature was raised to 60°C, and the reaction was carried out for 5h. Finally, under negative pressure conditions (vacuum gauge pressure was -0.095MPa), the low boiling point components were removed at 100°C for 60min to obtain the following transparent intermediate, which was hydrogen-containing polysiloxane.

[0059]

[0060] 2.2 Preparation of acetylenic alcohol modified polysiloxane:

[0061] 500 g of hydrogenated polysiloxane and Karstedt catalyst were added to storage tank 1, and the mixture was uniformly mixed to obtain component A. 736 g of butynediol polytetraoxyethylene ether was added to storage tank 2 as component B (m and n were both 2, and R was -OH); the molar ratio of the butynediol polytetraoxyethylene ether to the hydrogenated polysiloxane was 1:1, and the mass ratio of the total mass of the butynediol polytetraoxyethylene ether and the hydrogenated polysiloxane to the platinum element in the platinum-containing catalyst was 1 g:15 μg; the temperature of the microchannel reactor was set at 110° C., and after the temperature was stabilized, the mass flow rate of component A was adjusted to 50 g / min, and the mass flow rate of component B was adjusted to 60 g / min, and components A and B were transported to the reaction plate of the microchannel reactor for a hydrosilylation reaction; the product was received in a product tank, and after reacting for 15 minutes, an amber product, acetylene alcohol-modified polysiloxane, was obtained.

[0062]

[0063] Comparative Example 1

[0064] Add 510g of butynediol polyoxyethylene ether (m, n are both 1, R is -OH) and 200g of heptamethyltrisiloxane to the reactor, add 300g of heptamethyltrisiloxane to the constant pressure dropping funnel, turn on the reactor heating, and raise the temperature to 60°C. Then add Karstedt catalyst, the mass ratio of the total mass of butynediol polyoxyethylene ether and heptamethyltrisiloxane to the mass ratio of platinum element in the platinum-containing catalyst is 1g:15μg; continue to heat to 80°C after the addition is completed. After the temperature stabilizes, open the valve of the constant pressure dropping funnel, add heptamethyltrisiloxane dropwise, strictly control the temperature during the addition, and after the addition is completed, continue to keep the reaction at 100°C for 300min, end the reaction, and receive the product at the bottom of the reactor. The obtained acetylene alcohol modified polysiloxane product is dark in color.

[0065] Comparative Example 2

[0066] 2.1 Preparation of hydrogen-containing polysiloxane:

[0067] A 250 ml four-necked flask was thoroughly dried and nitrogen was passed through for 10 min. 48.6 g of hexamethyldisiloxane and 18 g of hydrogen-containing tetramethylcyclotetrasiloxane (D4 H ) and 44.4g octamethylcyclotetrasiloxane were placed in a four-necked flask, and then 5.0g of strong acid resin (HND-582) was added as a catalyst, the temperature was raised to 60°C, and the reaction was carried out for 5h. Finally, under negative pressure conditions (vacuum gauge pressure was -0.095MPa), the low boiling point components were removed at 100°C for 60min to obtain the following transparent intermediate, which was hydrogen-containing polysiloxane.

[0068]

[0069] 2.2 Preparation of acetylenic alcohol modified polysiloxane:

[0070] Add 496g of butynediol polytetraoxyethylene ether (m and n are both 2, R is -OH) and 300g of hydrogenated polysiloxane into the reactor. Add 200g of hydrogenated polysiloxane into the constant pressure dropping funnel, turn on the heating of the reactor, raise the temperature to 70°C, and then add the Karstedt catalyst, the mass ratio of the total mass of the butynediol polytetraoxyethylene ether and hydrogenated polysiloxane to the mass ratio of the platinum element in the platinum-containing catalyst is 1g:15μg; after the addition is completed, continue to heat to 85°C, after the temperature stabilizes, open the valve of the constant pressure dropping funnel, drop the hydrogenated polysiloxane, strictly control the temperature during the dropwise addition, after the dropwise addition is completed, continue to keep the temperature at 90°C for 300min, end the reaction, and receive the product at the bottom of the reactor. The obtained acetylene alcohol modified polysiloxane product is dark in color.

[0071] Evaluation Test

[0072] In order to obtain comprehensive and systematic evaluation results, a unified evaluation test was performed on all the embodiments and comparative examples. The evaluation method is as follows:

[0073] Test evaluation 1

[0074] Test the appearance of all the above products. Appearance was determined visually. Pour about 100g of sample into a clean, dry, colorless and transparent 250ml beaker and observe it under natural light indoors. The results are shown in Table 1.

[0075] Figure 1 This is a photographic comparison of the acetylene alcohol-modified polysiloxane obtained in Example 2 and the acetylene alcohol-modified polysiloxane obtained in Comparative Example 1, wherein the left side is Example 2 and the right side is Comparative Example 1.

[0076] Table 1 Appearance of acetylenic alcohol-modified polysiloxane

[0077]

[0078]

[0079] Test evaluation 2

[0080] The surface tension of all the above embodiments was tested. First, a 0.1% aqueous solution was prepared in a volumetric flask, using pure water; the aqueous solution was stabilized at 25°C ± 0.2°C; a static surface tension instrument was started; the platinum ring method was used; the corresponding value was measured; the test was repeated three times and the average value was taken, and the results were shown in Table 2.

[0081] Table 2 Surface tension test results of acetylenol modified polysiloxane

[0082] Surface tension (mN / s) Example 1 21.05 Example 2 21.23 Comparative Example 1 24.81 Comparative Example 2 25.17

[0083] Test evaluation 3

[0084] Test the Si-H bond conversion rate of all the above products

[0085]

[0086] The hydrogen content was calculated by the area ratio of the characteristic peaks through nuclear magnetic hydrogen spectrum (tritiated chloroform as solvent). The above formula was used to calculate the silicon-hydrogen bond conversion rate. The results are shown in Table 3.

[0087] The hydrogen nuclear magnetic resonance spectrum of the acetylenic alcohol-modified polysiloxane obtained in Example 1 is as follows: Figure 2 shown.

[0088] The hydrogen nuclear magnetic resonance spectrum of the acetylenic alcohol-modified polysiloxane obtained in Example 2 is as follows: Figure 3 shown.

[0089] Table 3 Si-H bond conversion rate test results

[0090] Si-H bond conversion rate Example 1 100％ Example 2 100％ Comparative Example 1 98％ Comparative Example 2 97％

[0091] Tables 1 to 3 show the performance comparison between the present invention using a microchannel reactor and a traditional kettle reaction. Compared with the traditional kettle reaction, the microchannel reaction time is shorter and the side reactions are fewer, so the appearance color is lighter. Within the limited reaction time, the silicon-hydrogen bond conversion rate of the microchannel reaction achieves 100% conversion and lower surface tension, which is also far beyond the reach of the traditional kettle reaction.

[0092] Evaluation 4 reaction heat test

[0093] According to GB / T42300-2022 "Specifications for Safety Risk Assessment of Fine Chemical Reactions", the reaction heat and decomposition heat of the addition reaction were tested. The RC1mx automatic reaction calorimeter produced by METTLER TOLEDO was used, with a 1L atmospheric pressure glass reactor, a glass reactor cover, a glass anchor stirring paddle, a 25W calibrated heater probe, a stirring speed of 180rpm, and the test method was the heat flow method.

[0094] The specific experimental operation is as follows: at room temperature, add 300g of heptamethyltrisiloxane to the reactor, start stirring, and heat to 90°C. Then add a platinum-containing catalyst, heat to 110°C after the addition is completed, and add butynediol polyoxyethylene ether (m, n are both 1, R is -OH) dropwise after stabilization, and heat for 120 minutes. Finally, read the total volume of the reactants after the reaction, measure the reaction heat of the system after the reaction, and the experiment ends.

[0095] Figure 4The heat release curve of this reaction process is shown in Figure 2. The orange-yellow bold curve is the reaction heat release rate curve. The heat release during the reaction process can be obtained by integrating the time. Figure 4 It can be seen that the heat released during the reaction is 15.778 kJ and 220.06 kJ; in this experiment, a total of 300 g of hydrogen-containing polysiloxane was added to the reactor, and the specific heat released based on hydrogen-containing polysiloxane was 786.13 kJ / kg.

[0096] Through the kettle reaction test, the specific heat release of the reaction based on hydrogen-containing polysiloxane is 786.13 kJ / kg. The reaction process hazard level is level 3. The decomposition heat of acetylene oxide polyether is large, which can easily cause the reaction materials to boil and cause the danger of material rushing, and even cause the instantaneous pressure of the system to increase, with a high potential explosion risk. Based on this, if the reaction is carried out in a microchannel reactor, the miniaturization of its scale can effectively avoid the rapid temperature rise of the reaction process, so as to avoid heat accumulation and material rushing, which is safer and more suitable for industrial-grade scale-up pilot production.

[0097] Evaluation 5 Wetting Performance Test

[0098] First, a 0.1% aqueous solution was prepared in a volumetric flask, 10 μL was taken with a pipette and dropped onto a PVC board, and its spreading speed and spreading area on the PVC board were observed. The results are shown in Table 5.

[0099] Table 5 Spreading performance test results

[0100] Spreading performance Example 1 The droplets spread and expand at a faster speed Example 2 The droplets spread and expand at a faster speed

[0101] Evaluation of 6 defoaming wetting agent application performance tests

[0102] Add 0.1g of 0.2% self-made defoaming wetting agent to 50g of paint (Aquolin 270, Wanhua). Take an appropriate amount and drop it on the tinplate sheet, and immediately scrape it flat with a wire rod applicator at a uniform speed to observe the shrinkage of the paint film on the tinplate sheet. 2 The number of shrinkage holes with a diameter greater than 1 mm on the area of ​​the paint film is used to measure the compatibility of the defoaming wetting agent with the paint. The fewer the number of shrinkage holes, the better the compatibility of the ultra-low foam wetting agent with the paint.

[0103] Table 6 Application performance test results

[0104] Applicability Example 1 No orange peel, no shrinkage, no shrinkage Example 2 No orange peel, no shrinkage, no shrinkage

[0105] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A nonionic acetylenic alcohol modified polysiloxane, characterized in that: Including the structure shown in formula (I): Here, x is an integer of 0 to 5, y is an integer of 1 to 5, m and n are each independently an integer of 0 to 10, and R is a hydroxyl group or a C1 to C10 alkoxy group.

2. The nonionic acetylenic alcohol-modified polysiloxane according to claim 1, characterized in that: The R is a hydroxyl group or a methoxy group.

3. A method for preparing a nonionic acetylenic alcohol-modified polysiloxane, characterized in that: The following steps are involved: S1) mixing hexamethyldisiloxane, D4H cyclotetrasiloxane and octamethylcyclotetrasiloxane, adding an acidic catalyst, and performing a ring-opening polymerization reaction to obtain a hydrogen-containing polysiloxane; S2) mixing the hydrogen-containing polysiloxane with a platinum-containing catalyst to obtain component A; introducing component A and butynediol polyoxyethylene ether represented by formula (II) into a microchannel reactor for hydrosilylation reaction to obtain a nonionic acetylenic alcohol-modified polysiloxane represented by formula (I); Here, x is an integer of 0 to 5, y is an integer of 1 to 5, m and n are each independently an integer of 0 to 10, and R is a hydroxyl group or a C1 to C10 alkoxy group.

4. The preparation method according to claim 3, characterized in that: The acidic catalyst is selected from acidic resins; The mass of the acidic catalyst is 1% to 8% of the total mass of hexamethyldisiloxane, D4H cyclotetrasiloxane and octamethylcyclotetrasiloxane.

5. The preparation method according to claim 3, characterized in that: The molar ratio of the butynediol polyoxyethylene ether represented by the formula (II) to the hydrogen-containing polysiloxane is 1 to 1.5:

1.

6. The preparation method according to claim 3, characterized in that: The platinum-containing catalyst in step S2) is selected from Speier catalyst and / or Karstedt catalyst; The mass ratio of the total mass of the butynediol polyoxyethylene ether represented by the formula (II) and the hydrogen-containing polysiloxane to the mass ratio of the platinum element in the platinum-containing catalyst is 1 g: 1 to 50 μg.

7. The preparation method according to claim 3, characterized in that: The total mass flow rate of component A in step S2) and the butine diol polyoxyethylene ether represented by formula (II) in the microchannel reactor is 20 to 120 g / min.

8. The preparation method according to claim 3, characterized in that: The temperature of the ring-opening polymerization reaction in step S1) is 40 to 100° C.; the time of the ring-opening polymerization reaction is 3 to 8 hours; The temperature of the hydrosilylation reaction in step S2) is 60-125°C.

9. Use of the nonionic acetylenic alcohol-modified polysiloxane according to claim 1 or 2 or the nonionic acetylenic alcohol-modified polysiloxane prepared by the preparation method of any one of claims 3 to 8 as a defoaming wetting agent.

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