CN115073961B - High-water-resistance water-based waterproof coating with flame retardance and preparation method thereof - Google Patents

Abstract

The invention belongs to the field of waterproof coatings, and particularly relates to a high-water-resistance waterproof coating with flame retardance and a preparation method thereof. The high-water-resistance water-based waterproof paint comprises the following raw materials: 40-50 parts of acrylic emulsion, 35-45 parts of filler, 6-10 parts of water and 2.5-5 parts of flame retardant modifier; the flame retardant modifier is hydroxyl silicone oil. The invention adopts hydroxyl silicone oil with a large number of active groups as the flame retardant modifier of the water-based waterproof paint, can effectively improve the stability and safety of the existing waterproof paint in high humidity and water environment, and keeps the efficient waterproof effect.

Description

High-water-resistance water-based waterproof coating with flame retardance and preparation method thereof

Technical Field

The invention belongs to the field of waterproof coatings, and in particular relates to a high-water-resistance waterproof coating with flame retardance and a preparation method thereof.

Background

Along with the development of various industries of national economy, the paint industry serving as a matched is gradually developed from a small unobtrusive industry to an important industry which is indispensable in various fields of national economy. The water-based waterproof paint is used as one of the paint, directly uses water as a dispersion medium, is nontoxic and odorless, and does not cause adverse effects on human bodies and the environment (compared with the water-based waterproof paint, most of organic solvents have adverse effects on the environment and human health). Secondly, the availability and the low cost of the dispersion medium make the water-based waterproof paint popular in the construction industry and the decoration industry. However, as a main constituent of the water-based waterproof paint, the resin, oil or emulsion is mostly composed of a polymer, which results in a high risk of fire in use.

At present, adding flame retardant substances into the paint and modifying high polymer organic matters in the paint are two main modes for realizing flame retardant modification of the paint. The Chinese patent application with publication number of CN 111378339A and publication date of 2020, 7 and 7 discloses a water-based flame retardant coating for building waterproofing, which mainly takes 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) added into the coating as a main flame retardant modified material; the Chinese patent application with publication number of CN 106810976A and publication date of 2017, 6 and 9 discloses a waterproof flame-retardant water-based paint which mainly uses water-soluble ammonium polyphosphate as a main flame-retardant material. Therefore, as an economic and efficient way, the direct addition of the flame retardant is an important way for flame-retardant modification of the water-based paint at the present stage.

The existing additive flame retardants for improving the flame retardant property of the water-based waterproof paint are mainly organic matters and inorganic matters with small molecules. When they are added to a paint, the combustion performance of the paint can be significantly improved, but there is a problem. These small molecule flame retardants such as magnesium hydroxide, calcium hydroxide, ammonium polyphosphate, etc. are extremely likely to precipitate from the inside of the coating film of the coating material in a moist and watery environment or dissolve in water in the environment, affecting the fire resistance of the coating material. In addition, some flame retardants such as DOPO, phosphates, etc., are prone to hydrolysis reactions of moisture in the environment. On one hand, the flame retardant property of the paint is reduced; on the other hand, the hydrolyzed product can react with the coating film, so that the performance of the coating film of the coating is reduced, and the subsequent use of the coating is affected.

The waterproof paint widely used in the market at present is mainly divided into acrylic acid paint and VAE paint, and the paint contains a large amount of high molecular compounds with active groups. So that the coating is extremely easy to generate phenomena such as swelling, fracture and the like due to the fracture of molecular chains in the coating film and the damage of a crosslinked network in the environment with moisture, and the performance and the use of the coating are seriously affected.

Disclosure of Invention

The invention aims to solve the problem of flame retardance and the problem of influence of moisture on the performance of a coating film of a paint.

In order to solve the problems, the invention prepares the high-water-resistance water-based waterproof paint with flame retardance by adding hydroxyl silicone oil with higher active groups and rich flame retardant elements into a system as a main flame retardant modifier.

The first aspect of the invention provides a high-water-resistance water-based waterproof coating with flame retardance, which comprises the following raw materials in parts by weight: 40-50 parts of acrylic emulsion, 35-45 parts of filler, 6-10 parts of water and 2.5-5 parts of flame retardant modifier; the flame retardant modifier is hydroxyl silicone oil.

In the components, the acrylic emulsion is taken as a main film forming substance, and emulsion particles are gradually aggregated and crosslinked along with the volatilization of moisture in the coating when the acrylic emulsion is coated on a concrete base layer, so that a compact waterproof film is finally formed; the filler (such as calcium carbonate) is a main filling and supporting substance, and plays a role in improving the strength and stability of a coating film when being coated on a waterproof film formed by polymer emulsion; the flame retardant modifier mainly takes hydroxyl silicone oil with active groups as main material, and plays a role in improving the flame retardant property and the water resistance of the coating film.

The innovation point (or improvement point) and key technical principle of the invention are as follows:

1. hydroxy silicone oil is a linear polymer with repeating siloxane bonds as the main chain, methyl groups as the side groups and hydroxyl terminated. Which contains a large amount of silicon element. And silicon can be rapidly separated from the compound in the combustion process, a heat-resistant barrier layer with a large number of Si-O bonds is formed on the surface of the material, the influence of heat and oxygen in the environment on the internal material is restrained, and the purpose of high-efficiency flame retardance is realized.

2. The hydroxyl silicone oil is colorless, transparent, odorless, and insoluble in organic solvents such as carbon tetrachloride, benzene, chloroform, diethyl ether, toluene, etc. As an auxiliary agent of the water-based waterproof paint, the water-based waterproof paint is not easy to separate out due to the influence of external moisture, and can maintain long-term flame retardant performance.

3. The active groups in the acrylic paint can be crosslinked with the hydroxyl groups in the hydroxyl silicone oil under the action of external force (heat, acid, alkali and the like). Thus, the aim of inhibiting the precipitation of the flame retardant can be further realized; but also can reduce the number of water absorbing groups in the paint, effectively inhibit the influence of moisture on the performance of the paint film and keep the high-efficiency waterproof effect.

The ratio of the acrylic emulsion to the hydroxyl silicone oil is 40-50:2.5-5, the formed water-based waterproof paint can maintain long-term flame retardant property and high-efficiency waterproof effect.

The hydroxyl silicone oil has the effect of improving the water resistance of the coating, and is mainly characterized in that the hydroxyl silicone oil reacts with active groups in the emulsion to reduce water absorption groups in the coating, so that the water resistance of the coating is improved. Possible crosslinking reactions are shown in FIG. 1. The hydroxyl groups at two ends of the hydroxyl silicone oil are subjected to alcoholysis reaction or transesterification reaction with ester groups on the side chains of the acrylic ester under the action of external force (heat, acid, alkali and the like), so that the hydroxyl silicone oil is fixed on the molecular chain of the acrylic ester to form a network structure with a certain crosslinking degree, and the purposes of fixing the hydroxyl silicone oil well and reducing the water absorption groups are achieved.

As a preferable scheme, the raw material composition of the Gao Naishui water-based waterproof paint further comprises at least one of the following components: 0-1 part of defoaming agent, 0-1 part of film forming auxiliary agent and 0-3 parts of pigment.

Among the components, the defoamer is used as an auxiliary material, and mainly eliminates air bubbles in the coating so as to improve the compactness of the coating; the film forming auxiliary agent can be added to effectively improve the flexibility of the latex particles, and promote the continuity of the coating film by promoting the swelling of the latex particles; pigments (such as titanium white slurry) are mainly used for adjusting the color of the paint and playing an attractive role.

As a preferable scheme, the hydroxyl value of the hydroxyl silicone oil is 8.5-10, and if the hydroxyl value is selected from the following: DOWSIL (Tao Xi or Dow chemical) company, colorless or pale yellow oily liquid, hydroxyl silicone oil with hydroxyl value of 8.5-10.

Preferably, the acrylic emulsion is Padlafu 230A.

Preferably, the filler is calcium carbonate, for example, the following materials are selected: changxing Huayuan powder material Co., ltd, the mesh number is 400 mesh calcium carbonate.

As a preferable scheme, the defoaming agent is an organosilicon-based defoaming agent, and if the following steps are selected: the defoaming agent of model H-137 is available from Dongguan, inc. of new materials.

As a preferable scheme, the film forming auxiliary agent is an alkali swelling association thickener, such as: water paint modified alkali swelling association type TT-935 thickener of Guangzhou Kogyuan chemical industry Co.

As a preferable scheme, the pigment is titanium white slurry, for example, the following materials are selected: titanium white slurry with model JL-SJ is available from Orixin building materials Co., ltd.

The second aspect of the present invention provides a method for preparing the flame-retardant high-water-resistance water-based waterproof paint, which comprises the following steps:

and mixing the acrylic emulsion with water and filler under the stirring state, and then mixing with a flame retardant modifier to obtain the high-water-resistance water-based waterproof coating with flame retardance.

The second aspect of the invention also provides a preparation method of the flame-retardant high-water-resistance water-based waterproof paint when an auxiliary agent is added, which comprises the following steps:

mixing the acrylic emulsion with water and filler under stirring, and then mixing with a flame retardant modifier to obtain the high-water-resistance water-based waterproof coating with flame retardance;

wherein, after adding water and/or flame retardant modifier, optionally adding defoamer;

wherein, after the filler is added, optionally, a pigment is added;

wherein, after adding water and defoamer, optionally, a film forming aid is added.

In the above method, the preferable mixing speed of the acrylic emulsion and water is 400-500 r/min.

In the method, as a preferable scheme, the mixing rotating speed is controlled to be 700-800 r/min before the film forming additive and the filler are added.

In the method, as a preferable scheme, the mixing rotating speed is controlled to be 1000-1200 r/min after the filler is added.

In the method, the rotation speed is controlled to be 600-700 r/min before the flame retardant modifier is added as a preferable scheme.

In the method, as a preferable scheme, the control speed is 400-500 r/min when the defoaming agent is added.

According to the invention, in one embodiment, the preparation method of the high-water-resistance water-based waterproof paint with flame retardance comprises the following steps: after the acrylic emulsion is metered, a liquid material stirring cylinder is added, a dispersing machine is started, the rotating speed is kept at 400-500 r/min, water and 1/2 defoamer are sequentially added, and stirring is carried out for 3min; then the rotation speed is increased to 700-800 r/min, the film forming additive is added, then 1/2 filler is added, stirring is carried out for 10min, the rotation speed is continuously increased to 1000-1200 r/min, the rest filler is added, and stirring is carried out for 15min; then the rotating speed is reduced to 600-700 r/min, pigment and flame retardant modifier are added in sequence, and stirring is carried out for 5min; finally, the rotating speed is reduced to 400-500 r/min, and the residual defoaming agent is slowly added. The required high-water-resistance waterproof paint with flame retardance is obtained.

The invention has the beneficial effects that:

1. the invention adopts hydroxyl silicone oil as the flame retardant modifier of the water-based waterproof paint, and effectively solves the problems of precipitation and easy hydrolysis existing in the existing flame retardants. And the effect of external moisture is less, and the long-term flame retardant property of the coating can be maintained.

2. The invention adopts hydroxyl silicone oil with a large amount of silicon elements as the flame retardant modifier of the water-based waterproof paint, and can effectively improve the fire safety of the existing waterproof paint.

3. The invention adopts hydroxyl silicone oil with a large number of active groups as the flame retardant modifier of the water-based waterproof paint, can effectively improve the stability and safety of the existing waterproof paint in high humidity and water environment, and keeps the efficient waterproof effect.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

FIG. 1 shows a schematic representation of a crosslinking reaction which may be present in the present invention.

Detailed Description

Preferred embodiments of the present invention will be described in more detail below. While the preferred embodiments of the present invention are described below, it should be understood that the present invention may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

In the embodiment of the invention, the sources of the components are respectively as follows:

acrylic emulsion: bard rich 230A;

calcium carbonate: changxing Huayuan powder materials limited company, mesh number: 400 mesh;

flame retardant modifier (hydroxy silicone oil): DOWSIL (Tao Xi or Dow chemical) company, colorless or pale yellow oily liquid, hydroxyl value 8.5-10;

defoaming agent: the Dongguan city is good and is a new material limited company, model H-137;

film forming auxiliary agent: water-based paint modified alkali swelling association type TT-935 thickener of Guangzhou Kogyuan chemical industry Co., ltd;

titanium white slurry: model JL-SJ of Suzhou Olixin building materials Co.

In the embodiment of the invention, each component is in parts by weight.

Example 1

Adding 450g of acrylic emulsion into a liquid material stirring cylinder, starting a dispersing machine, keeping the rotating speed at 450r/min, sequentially adding 80g of water and 5g of defoaming agent, and stirring for 3min; then the rotating speed is increased to 750r/min, 2.0g of film forming additive is added, then 200g of calcium carbonate is added, stirring is carried out for 10min, the rotating speed is continuously increased to 1100r/min, 200g of calcium carbonate is added, and stirring is carried out for 15min; then the rotating speed is reduced to 650r/min, 20g of titanium white slurry and 2.5g of flame retardant modifier are sequentially added, and stirring is carried out for 5min; finally, the rotational speed was reduced to 450r/min and 5g of defoamer was slowly added. The required waterproof paint is obtained.

Example 2

The difference from example 1 is that the flame retardant modifier is 3g.

Example 3

The difference from example 1 is that the flame retardant modifier is 5g.

Example 4

Adding 450g of acrylic emulsion into a liquid material stirring cylinder, starting a dispersing machine, keeping the rotating speed at 450r/min, adding 80g of water, and stirring for 3min; then increasing the rotating speed to 750r/min, adding 200g of calcium carbonate, stirring for 10min, continuously increasing the rotating speed to 1100r/min, adding 200g of calcium carbonate, and continuously stirring for 15min; then the rotating speed is reduced to 650r/min, 2.5g of flame retardant modifier is added, and the mixture is stirred for 5min; and finally, reducing the rotation speed and discharging. The required waterproof paint is obtained.

Comparative example 1

The difference from example 1 is that the flame retardant modifier is 0g.

Comparative example 2

The difference from example 1 is that the flame retardant modifier is 2g.

Comparative example 3

The difference from example 1 is that the flame retardant modifier is replaced by gamma-glycidoxypropyl trimethoxysilane (KH 560).

Comparative example 4

The difference from example 1 is that the flame retardant modifier is replaced by talc.

Test case

1. Flame retardant Performance test

The coatings of each example and comparative example were prepared to test coating films according to the requirements of the Standard GB/T23445-2009 Polymer Cement waterproof coating, respectively. Each group was then cut to obtain 3 test specimens 120.+ -. 0.5mm in length, 10.+ -. 05mm in width and 1.5.+ -. 0.2mm in thickness, and the Limiting Oxygen Index (LOI) of the standard test specimens was measured according to ASTM D2863-77. The sample limiting oxygen index test results are shown in table 1 below:

TABLE 1

Wherein the combustion grade is inflammable, flammable and flame-retardant, and the judgment conditions are shown in table 2:

TABLE 2

Oxygen index (%)	≤22	22＜LOI≤27	LOI＞27
				Combustion grade	Inflammable material	Combustible fuel	Flame retardant

As can be seen from table 1, the LOI of the waterproof coating film was 24.6% for the sample (comparative example 1) to which the flame retardant modifier was not added, indicating that the material was a flammable material, and had a high risk of fire. For the samples containing the flame retardant modifier, the LOI of the material is improved, the maximum LOI value is obviously higher than 27%, and the material achieves the flame retardant grade. The flame retardant modifier added in the invention can effectively improve the combustion grade of the prepared water-based waterproof paint, inhibit the combustion of the waterproof paint and reduce the fire risk.

As can be seen from Table 2, for comparative example 3, the flame retarding effect is much lower than that of the hydroxy silicone oil with the same amount of addition due to the lower content of silicon element of the modifier KH 560. In contrast, for comparative example 4, the talc powder, which is a mineral containing a large amount of magnesium silicate, contains abundant silicon and magnesium elements, and has a flame retardant effect significantly higher than that of hydroxy silicone oil when added in equal amounts.

2. Water resistance test

The coatings of each example and comparative example were each prepared into a test coating film according to the requirements of the Standard GB/T23445-2009 Polymer Cement waterproof coating. Then 5 test specimens each having a length of 120.+ -. 5mm, a width of 25.+ -. 5mm and a thickness of 1.5.+ -. 0.2mm were cut out from each group. Then the sample is soaked in water according to the requirements of the standard GB/T35609-2017 green product evaluation waterproof and sealing materials. The tensile strength of the untreated and immersed samples was then tested and the results are shown in tables 3 and 4:

TABLE 3 tensile strength test results for various embodiments of the invention

TABLE 4 tensile strength test results for each comparative example of the present invention

As can be seen from Table 3, the tensile strength of the coating film after immersion in water was significantly reduced in the sample (comparative example 1) to which the flame retardant modifier was not added, and the retention of tensile strength was only 41.28%, indicating that the performance of the waterproof coating film was impaired by water and the performance was reduced. While the tensile strength of the coating films after immersing in water is also reduced for the examples to which the flame retardant modifier is added, the maximum retention rate is 63.60% compared with the comparative examples. This demonstrates that the flame retardant modifier added in the invention can improve the water resistance of the waterproof paint. However, with increasing modifier content, the strength retention is not greatly improved, which is affected by the voids in the coating film, and the water in the environment enters into these voids, so that the water resistance cannot be further improved.

As can be seen from Table 2, for comparative example 3, since the modification agent KH560 forms a certain reactive group after hydrolysis, it also reacts with acrylic acid esters to form a certain crosslinking reaction, which in turn can also improve the water resistance of the coating. In contrast, in comparative example 4, talc, which is a mineral containing a large amount of magnesium silicate, was unable to effectively reduce the water-absorbing group and promote the crosslinking reaction of acrylic ester after being added into the paint, and thus was unable to improve the water resistance of the paint.

Therefore, the hydroxyl silicone oil meeting the content of certain components is selected, so that the obtained coating has high flame retardance and high water resistance.

The foregoing description of embodiments of the invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the various embodiments described.

Claims (9)

1. The application of the hydroxyl silicone oil in improving the flame retardance of the high-water-resistance water-based waterproof paint is characterized by comprising the following raw materials in parts by weight:

40-50 parts of acrylic emulsion, 35-45 parts of filler, 6-10 parts of water and 2.5-5 parts of flame retardant modifier;

the flame retardant modifier is hydroxyl silicone oil, and the hydroxyl value of the hydroxyl silicone oil is 8.5-10.

2. The use of claim 1, wherein the raw material composition of the Gao Naishui water-resistant coating further comprises at least one of the following components:

0-1 part of defoaming agent, 0-1 part of film forming auxiliary agent and 0-3 parts of pigment.

3. The use according to claim 1, wherein the acrylic emulsion is bard-rich 230A.

4. Use according to claim 1, wherein the filler is calcium carbonate.

5. The use according to claim 2, wherein the defoamer is a silicone-based defoamer.

6. The use according to claim 2, wherein the film forming aid is an alkali swellable associative thickener.

7. The use according to claim 2, wherein the pigment is titanium dioxide slurry.

8. The use according to any one of claims 1, 3, 4, wherein the method for preparing a highly water-resistant, water-borne waterproofing paint comprises:

and mixing the acrylic emulsion with water and filler under stirring, and then mixing with a flame retardant modifier to obtain the Gao Naishui water-based waterproof coating.

9. The use according to any one of claims 2, 5, 6, 7, wherein the method for preparing a highly water-resistant, water-borne waterproofing paint comprises:

mixing the acrylic emulsion with water and filler under stirring, and then mixing with a flame retardant modifier to obtain the Gao Naishui water-based waterproof coating;

wherein, after adding water and/or flame retardant modifier, optionally adding defoamer;

wherein, after the filler is added, optionally, a pigment is added;

wherein, after adding water and defoamer, optionally, a film forming aid is added.