CN111363446B

CN111363446B - Moisture-heat-resistant bi-component waterproof coating and preparation method thereof

Info

Publication number: CN111363446B
Application number: CN202010307018.1A
Authority: CN
Inventors: 姬振行; 王少华; 王宇川
Original assignee: Cetc Baoli Beijing Technology Co ltd
Current assignee: Cetc Baoli Beijing Technology Co ltd
Priority date: 2020-04-17
Filing date: 2020-04-17
Publication date: 2022-02-15
Anticipated expiration: 2040-04-17
Also published as: CN111363446A

Abstract

A damp-heat resistant bi-component waterproof coating and a preparation method thereof, the waterproof coating comprises A, B two components, the A component comprises modified acrylic resin emulsion; the component B comprises a curing agent; the raw materials of the modified acrylic resin comprise an epoxy resin monomer, a fluorine-containing vinyl silane monomer and an acrylic derivative monomer. The modified acrylic resin is obtained by reacting the epoxy monomer, the fluorine-containing vinyl silane monomer and the acrylic acid derivative, and the waterproof coating containing the film-forming substance not only combines good cohesiveness and chemical resistance of the epoxy resin and the acrylic resin, but also has good damp-heat stability. In addition, the modified acrylic resin, the fluorine-containing vinyl silane and the organic silicon leveling agent have a synergistic effect, the water resistance of the waterproof coating can be improved by adjusting the using amount of the fluorine-containing vinyl silane monomer and the using amount of the leveling agent, and the waterproof coating is suitable for cement-based walls, especially is coated on the cement-based walls and forms a three-proofing wall system together with the self-built polyurethane walls.

Description

Moisture-heat-resistant bi-component waterproof coating and preparation method thereof

Technical Field

The invention belongs to the technical field of coatings, and particularly relates to a damp-heat resistant two-component waterproof coating and a preparation method thereof.

Background

In the southern areas with high temperature and damp heat or in damp and hot underground engineering (such as a power distribution station room), cement concrete or mortar sometimes can be subjected to the physical and chemical actions of environmental water, so that the hardened cement stone structure is gradually destroyed and loses the protection function.

The waterproof paint for building is composed of base material, pigment, assistant, dispersing medium, etc. and may be acrylic waterproof paint with acrylic emulsion as base material, styrene-acrylic waterproof paint with styrene-acrylic emulsion as base material, etc. Among them, acrylic waterproof coatings are widely used due to their outstanding weather resistance and chemical resistance, but in practical use, they still have the disadvantages of poor adhesion, heat resistance, hardness, etc.; although epoxy resin has the characteristics of high strength and good adhesion, the epoxy resin has poor weather resistance, so that researchers modify acrylic resin by using epoxy resin to obtain a coating with complementary performance and higher value. Such as the patent: CN201810124584.1 discloses a waterproof coating and a preparation method thereof, the coating comprises 10-20% of bamboo pulp fiber, 1-9% of silica sol, 15-21% of titanium dioxide, 1-9% of clay, 1-4% of basalt fiber, 1-4% of silane waterproofing agent, 1-4% of fumed silica, 2-8% of silicon modified emulsion, 1-4% of film forming agent, 0.5-1.5% of thickening agent, 0.5-1.5% of flatting agent, 0.5-1.5% of dispersing agent, 0.1-0.4% of defoaming agent, 10% of water and the balance epoxy modified acrylic emulsion, compared with the prior art, the coating has good elasticity, is suitable for construction of a damp base surface, has strong cohesive force and good chemical resistance; patent CN201310216462.2 discloses a perchloro-ethylene resin-containing waterproof acid-and-alkali-resistant coating, which comprises 35 parts of perchloro-ethylene resin, 35 parts of epoxy acrylate, 15 parts of C5 hydrogenated petroleum resin, 15 parts of terpene resin, 15 parts of calcium carbonate, 15 parts of aluminum phosphate, 15 parts of diatomite, 15 parts of talcum powder, 15 parts of n-butyl alcohol and 60 parts of cyclohexanone, and the coating has good waterproofness and acid-and-alkali resistance. The waterproof coatings disclosed in the prior art all adopt the acrylic resin modified by the epoxy resin as a core material of a base material, so that good cohesiveness and chemical resistance are achieved, but in practical application, the modified acrylic resin is poor in heat and humidity resistance stability, a waterproof film formed by the waterproof coating is easy to reduce in mechanical property, and cannot adapt to structural deformation so as to play a role in long-term water resistance and impermeability, and particularly in a southern damp and hot area or a damp and stuffy underground engineering environment, if the water resistance and impermeability effect is poor, serious safety problems can occur, and particularly, damages such as electrical short circuit, electrical equipment flash explosion, mildew corrosion and the like can be caused to electrical equipment. Therefore, it is necessary to develop an acrylic waterproof coating material having excellent resistance to moist heat.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide a damp-heat resistant two-component waterproof coating and a preparation method thereof, wherein an epoxy monomer and a fluorine-containing vinyl silane monomer are used for modifying a common high-molecular film forming substance-acrylic acid derivative in a substrate to obtain a high-molecular film forming substance which has a certain cross-linking structure and contains fluorine and silicon elements in the structure.

In order to realize the purpose, the following specific technical scheme is adopted:

a wet-heat resistant two-component waterproof coating comprises A, B two components, wherein the A component comprises a modified acrylic resin emulsion; the component B comprises a curing agent; the raw materials of the modified acrylic resin comprise an epoxy resin monomer, a fluorine-containing vinyl silane monomer and an acrylic derivative monomer.

The component A comprises 70-100 parts by weight of modified acrylic resin emulsion; the component B comprises 20-35 parts by weight of curing agent.

The raw materials of the modified acrylic resin comprise 10-15 parts of epoxy resin, 5-10 parts of fluorine-containing vinyl silane monomer and 20-30 parts of acrylic acid derivative.

The alpha-H atom on the carbon adjacent to the ether bond of the epoxy resin monomer and the H atom on the tertiary carbon atom are relatively active and can form a free radical under the action of an initiator free radical, thereby initiating the graft polymerization reaction.

The fluorine-containing vinyl silane includes, but is not limited to, at least one of vinyl dimethyl fluoro silane, vinyl (trifluoromethyl) dimethylsilane and (1-fluorovinyl) methyl diphenylsilane.

Preferably, the fluorine-containing vinyl silane is (1-fluorovinyl) methyl diphenylsilane.

The epoxy resin monomer is bisphenol type epoxy resin monomer, preferably bisphenol A type epoxy resin.

Further, the epoxy value of the bisphenol A type epoxy resin is 0.2 to 0.6mol/100g, such as at least one of E-20, E-44, E-51, E-54 and E-56 epoxy resins.

The acrylic acid derivative comprises at least one of (meth) acrylic acid, alkyl (meth) acrylate and (meth) acrylamide, and is specifically selected from at least one of methyl acrylate, butyl methacrylate, methyl 2-methacrylate, tert-butyl acrylate, hydroxypropyl acrylate, acrylic acid, methacrylic acid and 2-methacrylamide.

The modified acrylic resin emulsion is prepared by a preparation method comprising the following steps:

s1: adding an emulsifier, an initiator, an epoxy resin monomer and deionized water into a container and stirring to obtain a pre-emulsified mixture;

s2: adding fluorine-containing vinyl silane monomers and acrylic acid derivative monomers into a polymerization kettle containing deionized water in a nitrogen atmosphere, uniformly stirring, and continuously keeping stirring;

s3: firstly, adding part of the pre-emulsified mixture into the reaction kettle in the step S2, heating the reaction kettle, keeping constant temperature reaction, then beginning to dropwise add the rest pre-emulsified mixture, and continuing constant temperature reaction after dropwise adding is finished;

s4: and (4) cooling the mixture obtained in the step S3, adding a pH regulator, regulating the pH of the mixture to be neutral, and filtering a small amount of aggregate to obtain the modified acrylic resin emulsion.

The emulsifier in step S1 has no special requirement, and is commonly used in the field, including but not limited to alkylphenol ethoxylates OP-10, sodium dodecyl sulfate; the initiator is a peroxy initiator, including but not limited to at least one of dibenzoyl peroxide, potassium persulfate and ammonium persulfate.

In the step S3, the amount of the S1 mixture added into the reaction kettle is 1/4-1/2 of the total mass, the temperature of the reaction kettle is increased to 80-140 ℃, the first constant-temperature reaction time is 0.2-1.5h, and the constant-temperature reaction time is 1-3h after dripping is finished.

The pH adjusting agent used in step S4 is not particularly limited, and may be one commonly used in the art, including but not limited to at least one of ammonia, triethylamine, and triethanolamine.

The component A can also comprise 10-30 parts of filler, 1-5 parts of dispersant, 1-5 parts of thickener, 1-3 parts of flatting agent, 1-3 parts of defoaming agent and 10-60 parts of water.

The component B can also comprise 1-5 parts of thickening agent, 1-5 parts of mildew preventive, 1-5 parts of bactericide and 50-80 parts of water.

The filler is selected from at least one of calcium carbonate, mica powder, wollastonite and silicon dioxide.

The dispersant is an anionic dispersant, and is specifically selected from at least one of sodium oleate, sulfate ester salt and sulfonate. Such as sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, sodium humate (HA-Na), sodium naphthalene Sulfonate (SN), sodium lignosulfonate (CMN). The thickener is at least one selected from cellulose thickener, associated polyurethane thickener, polyacrylic acid thickener, and inorganic thickener, specifically at least one selected from methylcellulose, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, aluminum silicate, and bentonite.

The leveling agent comprises at least one of organic silicon and fluorocarbon surfactant.

Preferably, the leveling agent is alkyl modified organic siloxane in the organosilicon surfactant, and is specifically selected from at least one of stearyloxydimethylsilane, behenyloxysiloxane and lauryl dimethyl siloxane.

The defoaming agent is at least one of a silicone defoaming agent and a polyether defoaming agent.

The curing agent is a polyamine curing agent, and includes but is not limited to at least one of an aliphatic polyamine curing agent, an alicyclic polyamine curing agent, an aromatic amine curing agent and a phenolic aldehyde modified amine curing agent. Specifically, the diamine may be selected from ethylenediamine, hexamethylenediamine, m-phenylenediamine, m-xylylenediamine, a condensate of phenol, formaldehyde and xylylenediamine, and a condensate of phenol, formaldehyde and tetraethylenepentamine.

The mildew preventive comprises at least one of 2-n-octyl-4-isothiazoline-3-ketone, 4, 5-dichloro-2-n-octyl-4-isothiazoline-3-ketone, 3-iodine-2-propynyl butyl carbamate and 2-butyl-1, 2-phenylpropyl isothiazoline-3-ketone.

The bactericide comprises at least one of a cason bactericide, a BIT bactericide, an s-triazine bactericide, a Brobopol bactericide and a DBNPA bactericide.

The preparation method of the two-component waterproof coating comprises the following steps: weighing corresponding raw materials in the component A, and uniformly mixing to obtain a component A for later use; weighing corresponding raw materials in the component B, and uniformly mixing to obtain a component B for later use; the component A and the component B are uniformly mixed according to a certain proportion, and then spraying and brushing are carried out, wherein the thickness of the coating is 1-2 mm.

The weight ratio of the component A to the component B is 1-3: 1.

The invention also provides the application of the bi-component coating as a waterproof coating on a cement-based wall, in particular to the application as a waterproof coating on a cement-based wall and between the cement-based wall and a self-built polyurethane wall.

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

the invention utilizes epoxy monomer, fluorine-containing vinyl silane monomer and acrylic acid derivative to react to obtain modified acrylic resin, the modified acrylic resin is a high molecular film forming substance which has a certain cross-linking structure and contains fluorine and silicon elements in the structure, and the waterproof coating containing the film forming substance not only combines good cohesiveness and chemical resistance of the epoxy resin and the acrylic resin, but also has good damp-heat stability.

Secondly, the inventors have unexpectedly found that the fluorine-containing vinyl silane as the modifying substance and the organosilicon surfactant in the leveling agent have a synergistic effect, and the water resistance of the waterproof coating can be further improved by adjusting the amount of the fluorine-containing vinyl silane monomer and the amount of the leveling agent.

And thirdly, the film forming substance in the waterproof coating substrate prepared by the invention has short solidification time, is used on a cement-based wall body, is positioned between the cement-based wall body and a self-built polyurethane wall body, and is used as a waterproof coating, so that the damp-heat stability is good, and the waterproofness is good.

Detailed Description

The present invention will be further described with reference to the following examples, but the present invention is not limited to the descriptions in the following. Unless otherwise specified, "parts" in the examples of the present invention are parts by weight. All reagents used are commercially available in the art.

Unless otherwise specified, "parts" in the examples of the present invention mean parts by weight.

Preparation of modified acrylic resin emulsion

Preparation example 1

S1: adding 2.4 parts of alkylphenol polyoxyethylene OP-10, 1.2 parts of sodium dodecyl sulfate, 1 part of dibenzoyl peroxide as an initiator, 0.2 part of potassium persulfate, 10 parts of E-44 as an epoxy monomer and 100 parts of deionized water into a container for stirring to obtain a pre-emulsified mixture for later use;

s2: adding 10 parts of (1-fluorovinyl) methyl diphenylsilane and 20 parts of butyl methacrylate into a polymerization kettle containing deionized water under the nitrogen atmosphere, uniformly stirring, and continuously keeping stirring;

s3: firstly, adding the pre-emulsified mixture obtained in the step S1 of 1/3 into a reaction kettle obtained in the step S2, heating the reaction kettle to 90 ℃, keeping the temperature constant for reaction for 48min, beginning to dropwise add the rest of the pre-emulsified mixture obtained in the step S1, and continuing to perform constant temperature reaction for 2h after dropwise adding;

s4: the mixture obtained in step S3 was cooled to 23 ℃, aqueous ammonia was added, the pH of the mixture was adjusted to 7, and the aggregate was filtered to obtain modified acrylic resin emulsion 1 (the modified acrylic resin emulsions prepared in the following preparation examples are referred to as modified acrylic resin emulsions 2 to 6 in order).

Preparation example 2

The procedure was repeated, except that 15 parts of epoxy monomer E-44 was used.

Preparation example 3

The procedure was repeated, except that 30 parts of butyl methacrylate was used.

Preparation example 4

The same as in preparation example 1 except that (1-fluorovinyl) methyldiphenylsilane was used in an amount of 5 parts.

Preparation example 5

The same as in preparation example 1 except that (1-fluorovinyl) methyldiphenylsilane was used in an amount of 3 parts.

Preparation example 6

The same as in preparation example 1 except that (1-fluorovinyl) methyldiphenylsilane was used in an amount of 15 parts.

Comparative preparation example 1

The procedure was as in preparation example 1 except that (1-fluorovinyl) methyldiphenylsilane was not used.

The modified acrylic emulsions prepared in the above preparation examples and comparative preparation examples were subjected to the following performance tests, and the results are shown in Table 1.

Determination of the solid content of the emulsion:

weighing 2g of emulsion sample in a drying green tray, placing the emulsion sample in an oven at 110 ℃ for drying until the weight is constant, and calculating the solid content according to the following formula

X is solid content; m mass of the aluminum plate, g; m is₁Mass of sample and aluminum pan before drying, g; m is₂The mass of the sample and the aluminum pan after drying, g.

Testing of centrifugal stability:

injecting a proper amount of emulsion sample into a 5ml plastic centrifuge tube, placing the tube into a centrifuge, rotating at 5000r/min, observing for 1h, and performing non-layering demulsification to pass a centrifugal stability test.

Determination of Tg of the modified acrylic resin emulsion:

DSC analysis is carried out by using MDSC 2910, the temperature rise interval is-20-100 ℃, the temperature rise rate is 20 ℃/min, and the Tg of the emulsion is measured.

TABLE 1

	Solids content/%	Centrifugal stability	Tg/℃
				Preparation example 1	47.36	By passing	-5.89
Preparation example 2	46.12	By passing	-4.32
				Preparation example 3	47.81	By passing	-5.14
Preparation example 4	47.29	By passing	-6.11
				Preparation example 5	47.63	By passing	-6.56
Preparation example 6	47.48	By passing	-8.98
				Comparative preparation example 1	45.77	By passing	-2.44

Preparation of two-component waterproof coating

Example 1

A component A, wherein the component A: 100 parts of modified acrylic resin emulsion 1, 20 parts of calcium carbonate, 4 parts of sodium oleate, 5 parts of hydroxymethyl cellulose, 3 parts of behenoxy siloxane, 3 parts of defoaming agent SN-345 (Nippon Nupu's assistant Co., Ltd.), and 20 parts of deionized water.

A component B, wherein the component B: 35 parts of hexamethylene diamine, 3 parts of hydroxymethyl cellulose, 3 parts of 4, 5-dichloro-2-n-octyl-4-isothiazoline-3-ketone, 3 parts of 1, 2-benzisothiazolin-3-ketone and 60 parts of deionized water.

1. Weighing the raw materials of the component A, and uniformly mixing to obtain a component A for later use;

2. weighing the raw materials included in the component B, and uniformly mixing to obtain a component B for later use;

3. the component A and the component B are uniformly mixed according to the proportion of 1:1 and coated, and the thickness of the coating is 1.5 mm.

Examples 2 to 6

The same as in example 1 except that the modified acrylic resin emulsions used in examples 2 to 6 respectively correspond to the modified acrylic emulsions 2 to 6 prepared in preparation examples 2 to 6.

Example 7

The process was repeated as in example 1 except that the leveling agent, behenoxy siloxane, was used in an amount of 1 part.

Example 8

The balance of the process is the same as that of example 1, except that 70 parts of modified acrylic resin emulsion in the component A and 25 parts of hexamethylene diamine in the component B are weighed and mixed uniformly according to the ratio of 1: 1.

Example 9

The rest is the same as the example 1, except that the component A and the component B are uniformly mixed according to the ratio of 3: 1.

Example 10

The process was repeated as in example 1, except that the leveling agent used was fluorocarbon surfactant-FSN-100 (DuPont, USA).

Comparative example 1

The same as in example 1 except that the modified acrylic resin emulsion used was prepared in comparative preparation example 1.

The coatings prepared in the above examples and comparative examples were subjected to the following performance tests, and the results are shown in Table 2.

Performance testing

Flexibility: when the paint film is bent by external force, the comprehensive performance of elasticity, plasticity, adhesive force and the like becomes flexibility; the test was carried out with reference to the standard GB/T1731-93.

Moisture and heat resistance stability: the test was carried out according to the standard GB/T1740-2007, and the flexibility test was carried out again.

Water resistance: the test was carried out according to the immersion test method in the standard GB/T1733-93, at 23. + -. 2 ℃.

Adhesion force: the test was carried out with reference to the standard GB/T9286-1998.

The adhesion force is divided into 5 grades

The 0-level cutting edge is complete and smooth and has no shedding phenomenon

Less than 5% of the coating of grade 1 is detached

The shedding area of the 2-grade coating is within the range of 5-15 percent

The cutting edge of the 3-grade coating is fallen or the whole area is fallen by more than 15 percent and less than 35 percent in a large area

The shedding area of the 4-grade coating is within the range of 35-65 percent

Surface drying time and actual drying time: the test was carried out with reference to the standard GB/T1728-89.

TABLE 2

The modified acrylic resin is a high-molecular film-forming substance which has a certain cross-linking structure and contains fluorine and silicon elements in the structure, and the waterproof coating containing the film-forming substance not only combines good cohesiveness and chemical resistance of the epoxy resin and the acrylic resin, but also has good damp-heat stability.

The invention unexpectedly discovers that the modified substance, namely the fluorine-containing vinyl silane and the organic silicon surfactant in the leveling agent have a synergistic effect, and the water resistance of the waterproof coating can be improved by adjusting the using amount of the fluorine-containing vinyl silane monomer and the using amount of the leveling agent.

The film forming substance in the waterproof coating base material prepared by the invention has short solidification time, good damp-heat stability and good waterproofness, and is particularly suitable for being used on a cement-based wall body and positioned between the cement-based wall body and a self-built polyurethane wall body to be used as a waterproof coating.

The above detailed description is specific to one possible embodiment of the present invention, and the embodiment is not intended to limit the scope of the present invention, and all equivalent implementations or modifications without departing from the scope of the present invention should be included in the technical scope of the present invention.

Claims

1. A damp-heat resistant two-component waterproof coating comprises a component A and a component B, wherein the component A comprises a modified acrylic resin emulsion; the component B comprises a curing agent; the acrylic resin is characterized in that raw materials of the modified acrylic resin comprise epoxy resin, fluorine-containing vinyl silane monomer and acrylic derivative monomer;

s1: adding an emulsifier, an initiator, epoxy resin and deionized water into a container and stirring to obtain a pre-emulsified mixture;

s3: firstly, adding part of the pre-emulsified mixture into the reaction kettle in the step S2, heating the reaction kettle, keeping constant temperature reaction for the first time, then beginning to dropwise add the rest pre-emulsified mixture, and continuing constant temperature reaction after dropwise adding;

s4: cooling the mixture obtained in the step S3, adding a pH regulator, regulating the pH of the mixture to be neutral, and filtering out a small amount of aggregate to obtain modified acrylic resin emulsion;

the component A comprises 70-100 parts by weight of modified acrylic resin emulsion and 1-3 parts by weight of flatting agent; the component B comprises 20-35 parts by weight of curing agent; the flatting agent is at least one of stearyloxy dimethylsilane, behenoxy siloxane and lauryl dimethyl siloxane; the raw materials of the modified acrylic resin comprise 10-15 parts of epoxy resin, 5-10 parts of fluorine-containing vinyl silane monomer and 20-30 parts of acrylic derivative monomer; the fluorine-containing vinyl silane includes at least one of vinyl dimethyl fluoro silane, vinyl (trifluoromethyl) dimethylsilane and (1-fluorovinyl) methyl diphenylsilane.

2. The two-component waterproof coating material according to claim 1, wherein the acrylic acid derivative monomer is at least one selected from the group consisting of (meth) acrylic acid, alkyl (meth) acrylate, and (meth) acrylamide.

3. The two-component waterproof coating material of claim 1, wherein the epoxy resin is a bisphenol type epoxy resin.

4. The two-component waterproof coating material of claim 3, wherein the epoxy resin is a bisphenol A type epoxy resin.

5. The two-component waterproof coating material according to claim 4, wherein the epoxy value of the bisphenol A type epoxy resin is 0.2 to 0.6mol/100 g.

6. A process for preparing the two-component waterproof coating material according to any one of claims 1 to 5, comprising the steps of: weighing corresponding raw materials in the component A, and uniformly mixing to obtain a component A for later use; weighing corresponding raw materials in the component B, and uniformly mixing to obtain a component B for later use; and (3) uniformly mixing the component A and the component B according to the ratio of 1-3:1, and spraying and brushing.

7. Use of the two-component coating according to any one of claims 1 to 5 as a waterproof coating on a cement-based wall, between a cement-based wall and a self-built polyurethane wall, as a waterproof coating.