CN112409898A

CN112409898A - Waterproof coating and preparation method and application thereof

Info

Publication number: CN112409898A
Application number: CN202011185906.7A
Authority: CN
Inventors: 梁亚涛
Original assignee: Guangdong Jushi Technology Research Co ltd
Current assignee: Guangdong Jushi Technology Research Co ltd
Priority date: 2020-10-30
Filing date: 2020-10-30
Publication date: 2021-02-26

Abstract

The invention belongs to the technical field of coatings, and discloses a waterproof coating as well as a preparation method and application thereof. The coating comprises a component A and a component B; the component A comprises: graphene and a curing agent; the component B comprises: resin, filler and auxiliary agent; the volume ratio of the component A to the component B is 1 (1-3.5); the resin contains-NH-. According to the invention, graphene is dispersed in the curing agent, and the component A is obtained without adding a dispersing agent, is in a paste state of pseudo dispersion, and is not easy to settle and not easy to agglomerate quickly; before the coating is used, the coating is mixed with a component B containing resin, a filler and a dispersant to form a stable dispersion state in a short time, and the dispersion is good before curing; due to the introduction of the graphene, the waterproof performance, hardness and wear resistance of the coating are enhanced. In addition, the addition of more graphene can also endow the coating with new properties, such as antistatic property; the coating has wide application in the aspect of house water resistance.

Description

Waterproof coating and preparation method and application thereof

Technical Field

The invention belongs to the technical field of coatings, and particularly relates to a waterproof coating as well as a preparation method and application thereof.

Background

Since the 50 s of the last century, architectural waterproof coatings have begun to be used on a large scale. In the widely used building waterproof coatings in the current market, polyurethane waterproof coatings, polymer cement waterproof coatings, acrylic waterproof coatings and modified asphalt waterproof coatings are mainly used, wherein the market proportion of the polyurethane waterproof coatings is more than 40%.

The polyurethane waterproof coating has excellent elasticity and low-temperature flexibility, is high in volume production and various in types, mainly takes a solvent type as a main material, but also has the problems of poor mechanical property of a paint film, easiness in cracking, easiness in falling and the like. The polyurea coating belongs to one of polyurethane coatings, has the advantages of good flexibility, no cracking, good chemical resistance, high curing speed and the like, and can be widely applied to water resistance and corrosion resistance. Although polyurea coatings have shown very excellent properties as waterproof coatings, problems are still exposed during use, such as too fast drying speed and the need for large spray equipment, and due to too fast drying, concentrated heat release, large heat shrinkage force and large internal stress. Through continuous improvement, the polyaspartic acid ester polyurea coating can slow down the condensation speed of the coating and improve the performance of a paint film. However, the polyaspartic acid ester resin has few types and single coating performance, and although the performance can be optimized by modifying the resin, the modification steps are complicated, and the performance optimization is not ideal.

Graphene is a polymer made of carbon atoms in sp²The honeycomb planar film formed by the hybridization mode has a unique two-dimensional nano structure, has the advantages of high electron transmission rate, good electrical conductivity, high thermal conductivity and the like, is the thinnest but the hardest nano material with the best electrical and thermal conductivity at present, and has good application prospects in the fields of physics, materials science, electronic information, computers, aerospace and the like.

Graphene oxide modified according to the prior art is reacted with-NCO groups in the blocked isocyanate prepolymer to obtain a product with anticorrosion and flame-retardant functions. But the graphene oxide modification process needs high-temperature treatment, then ultrasonic treatment, water washing and drying are carried out, modified graphene oxide is obtained through low-temperature plasma activation treatment, and a modified product is obtained through reaction with a blocked isocyanate prepolymer; although the graphene oxide can also be applied to the asparagus polyurea waterproof coating, the whole graphene oxide modification step is complicated, the cost is relatively high, and the graphene oxide is not suitable for large-scale production; and the oxygen-containing functional groups in the graphene oxide contain-OH, -COOH, epoxy functional groups and the like, and the ratio distribution is different, so that the-NCO value of the component prepared by using the graphene oxide as the chain extender fluctuates greatly, and the stability of the product is easily influenced. In the prior art, it is also described that graphene and perhydropolysilazane are ground in dry nitrogen to allow the graphene to fully adsorb the perhydropolysilazane, and then the mixture is mixed with isocyanate and reacted with an aminopolyether/amine chain extender to prepare a graphene polyurea coating. The graphene-loaded perhydropolysilazane is introduced into the coating, and a compact silicon dioxide layer is formed along with the influence of water, oxygen and ammonia environments in the process of forming the coating, so that the passing of moisture is blocked, and the compactness and continuity of the coating are improved. That is, the graphene in this embodiment is only used as a carrier for generating a silica layer having a moisture barrier effect by the reaction. However, the dispersion stability state of graphene in the system in the technology cannot be known, and the improvement of graphene on the performance of the waterproof coating after the introduction of graphene-supported perhydropolysilazane cannot be known.

In addition, in the prior art, the coating prepared by using the graphene and the derivatives thereof cannot solve the dispersion problem of the graphene, the waterproof performance of a coating formed by the prepared coating cannot be guaranteed, and in addition, the wear resistance, hardness and antistatic performance of the coating are poor. Therefore, it is necessary to provide a waterproof coating material containing graphene, which has stable dispersion of graphene, and a coating layer formed by the coating material has good waterproof performance, wear resistance, hardness and antistatic performance.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art described above. Therefore, the waterproof coating contains graphene, the graphene is not used as a chain extender or a carrier, the dispersion stability of the graphene in the coating is good, a coating formed by the coating has good waterproof performance, and in addition, the coating also has good mechanical performance and antistatic performance.

The invention principle of the invention is as follows: after graphene and a curing agent are mixed and homogenized, due to poor compatibility of the graphene and the curing agent, the formed slurry does not completely coat the graphene and is a paste. The graphene in the state is not easy to agglomerate and settle, can be secondarily dispersed in a resin system through simple mechanical stirring when being mixed with polyaspartic acid ester resin, and can form a good dispersion state in a short time due to the existence of a dispersing agent. And after the resin and the curing agent are mixed, the curing agent can be cured in a short time, and the problem of graphene sedimentation does not exist. The coating is coated on the carrier, and after the paint film is dried completely, a barrier layer is formed by a lamellar structure formed by flatly laying graphene, so that moisture is more difficult to permeate into the paint film, and the waterproof performance of the paint film is further enhanced. Meanwhile, the sheet-surface structure of the graphene improves the mechanical property of a paint film, so that the hardness and the wear resistance of the paint film are improved. When the addition amount of the graphene exceeds 2%, excellent antistatic performance can be given to the paint film.

A waterproof coating comprises a component A and a component B;

the component A comprises: graphene and a curing agent;

the component B comprises: resin, filler and auxiliary agent;

the volume ratio of the component A to the component B is 1 (1-3.5);

the resin contains-NH-.

Preferably, the viscosity of the curing agent is less than 600cps at 25 ℃; further preferably, the viscosity of the curing agent is less than 500cps at 25 ℃.

Preferably, the curing agent is selected from at least one of hexamethylene diisocyanate trimer (HDI trimer), isophorone diisocyanate (IPDI) or diphenylmethane diisocyanate (MDI).

Preferably, the particle size of the graphene is 1-50 μm; more preferably, the particle size of the graphene is 10 μm to 40 μm. The particle size of the graphene is less than 50 mu m, and the surface of a coating formed by the prepared coating is smooth.

Preferably, the mass ratio of the graphene to the curing agent is (1-10): (90-99); more preferably, the mass ratio of the graphene to the curing agent is (1-8): (92-99).

Preferably, the resin is a polyaspartic acid ester resin and/or a polyureaurethane resin.

Further preferably, the polyaspartic acid ester resin is selected from at least one of NH1520, NH1420, NH1220 of koste polymer limited or F520, F420, F220 of sekkaido chemical limited (NH1520, NH1420, NH1220, F520, F420, F220 represent brands).

Preferably, the filler is selected from at least one of titanium dioxide, mica powder or kaolin.

Preferably, the auxiliary agent includes at least one of a defoaming agent, a leveling agent, or a dispersing agent.

Preferably, the antifoaming agent is at least one selected from BYK141, TEGO Airex932 and Rhodoline DF6002(BYK141, TEGO Airex932 and Rhodoline DF6002 are the grades of antifoaming agents)

Preferably, the leveling agent is selected from BYK310, Levelolp 410 or

Resin (BYK310, Levelolp 410 or

Resin is the mark of the leveling agent).

Preferably, the dispersant is selected from at least one of BYK161, BZ203 or AKN2276(BYK161, BZ203 or AKN2276 is the brand of dispersant).

Preferably, the mass ratio of the resin, the filler and the auxiliary agent is (40-95): (3-50): (0.5-8); further preferably, the mass ratio of the resin, the filler and the auxiliary agent is (50-90): (5-48): (1-5).

Preferably, the volume ratio of the component A to the component B is 1 (1.5-4.5); further preferably, the volume ratio of the component A to the component B is 1 (1.5-3); more preferably, the volume ratio of the A component to the B component is 1: 2.

Further preferably, the molar ratio of the a component to the B component in terms of functional groups is-NCO/-NH ═ 1.0 to 1.2: 1.0; more preferably, the molar ratio of the a-component to the B-component in terms of functional groups is-NCO/-NH- ═ 1-1.05: 1. Wherein, -NCO is provided by the curing agent in the A component, -NH-is provided by the resin in the B component.

Another aspect of the present invention provides a method for preparing the above waterproof coating material.

Specifically, the preparation method of the waterproof coating comprises the following steps:

mixing graphene and a curing agent, uniformly stirring for the first time, and homogenizing and dispersing to obtain a component A;

mixing the resin, the filler and the auxiliary agent, uniformly stirring for the second time, and grinding and dispersing to obtain a component B;

and mixing the component A and the component B, and stirring for the third time to obtain the waterproof coating.

Preferably, the coating is mixed and stirred with the component A and the component B before use, and the performance of the coating is optimal.

Preferably, the preparation method of the graphene is a conventional method in the prior art, and comprises a physical method or a chemical method, wherein the graphene is dried at the temperature of 115-125 ℃ for 1.5-2.5 hours before use; further preferably, the graphene is dried at 120-125 ℃ for 1.5-2 hours before use.

Preferably, the speed of the first stirring is 450-1400 rpm, and the stirring time is 10-40 minutes; further preferably, the speed of the first stirring is 500-.

Preferably, the homogeneous dispersion is high-pressure homogeneous dispersion, and the pressure of the homogeneous dispersion is 95-110 MPa; further preferably, the pressure for the homogeneous dispersion is 100-110 MPa.

Further preferably, the number of times of the homogeneous dispersion is 4 to 10; more preferably, the number of times of the homogeneous dispersion is 5 to 8 times.

Preferably, the speed of the second stirring is 500-1200 r/min, and the stirring time is 30-150 min; further preferably, the speed of the second stirring is 500-.

Preferably, the grinding dispersion is grinding dispersion by a sand mill, the particle diameter of zirconium beads used in the grinding dispersion process is 0.1-2mm, the rotating speed is 2000-2800 r/min, and the grinding times are 4-15; more preferably, the particle size of the zirconium beads used in the grinding and dispersing process is 0.1-1mm, the rotation speed is 2000-2500 rpm, and the grinding times are 5-10 times.

Preferably, the third stirring speed is 200-550 revolutions per minute, and the stirring time is 5-15 minutes; further preferably, the third stirring speed is 200-500 rpm, and the stirring time is 5-10 minutes.

The invention also provides an application method of the coating, which comprises the following steps:

and mixing the component A and the component B in the coating, coating and curing.

Another aspect of the present invention provides the use of the above-described water-repellent coating.

In particular to the application of the waterproof coating in the waterproofing of houses.

Preferably, the house waterproofing comprises wall waterproofing or floor drainage.

The roof, wall surface, toilet floor or kitchen floor of a house are the most water-leakage places, and the water leakage problem of the house can be well solved by adopting the waterproof coating.

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

(1) according to the invention, graphene is dispersed in the curing agent, and the component A is obtained without adding a dispersing agent, is in a paste state of pseudo dispersion, and is not easy to settle and not easy to agglomerate quickly; the coating material is mixed with a component B containing a resin, a filler and a dispersant before use to form a stable dispersion state in a short time, and the dispersibility is good before curing.

(2) The coating formed by the coating disclosed by the invention has the advantages that due to the introduction of the graphene, the waterproof performance, the hardness and the wear resistance of the coating are enhanced. In addition, the addition of more graphene can also impart new properties to the coating, such as antistatic properties and the like.

(3) The preparation method of the coating is simple, short in flow, mild in reaction condition, low in cost, easy for large-scale production, and wide in application prospect, and especially has wide application in the aspect of house water resistance.

Detailed Description

In order to make the technical solutions of the present invention more apparent to those skilled in the art, the following examples are given for illustration. It should be noted that the following examples are not intended to limit the scope of the claimed invention.

The starting materials, reagents or apparatuses used in the following examples are conventionally commercially available or can be obtained by conventionally known methods, unless otherwise specified. The following "parts" are all referred to as "parts by mass" unless otherwise specified.

Example 1: preparation of the coating

A preparation method of a waterproof coating comprises the following steps:

mixing 2 parts of graphene and 98 parts of HDI trimer, uniformly stirring for the first time at a stirring speed of 500 revolutions per minute for 10 minutes, and then performing homogeneous dispersion for 5 times under the pressure of 100MPa to obtain a component A;

200 parts of polyaspartic acid ester resin (100 parts of NH1420, and the other 100 parts of NH1520), 120 parts of mica powder and 5.8 parts of auxiliary agent (the auxiliary agent comprises 5 parts of BYK161 dispersant, 0.5 part of BYK141 defoamer and 0.3 part of BYK310 flatting agent) are mixed and uniformly stirred for the second time, the stirring speed for the second time is 500 r/min, the stirring time is 60 min, the grinding and the dispersion are carried out, the particle size of zirconium beads used in the grinding and the dispersion processes is 0.5mm, the rotating speed is 2000 r/min, and the grinding times are 5 times, so that a component B is obtained;

and mixing the component A and the component B according to the volume ratio of 1:2, stirring for the third time, wherein the stirring speed for the third time is 200 revolutions per minute, and the stirring time is 5 minutes to prepare the waterproof coating.

Example 2: preparation of the coating

A preparation method of a waterproof coating comprises the following steps:

mixing 5 parts of graphene and 95 parts of HDI trimer, uniformly stirring for the first time at a stirring speed of 500 revolutions per minute for 10 minutes, and then performing homogeneous dispersion for 5 times under the pressure of 100MPa to obtain a component A;

200 parts of polyaspartic acid ester resin (100 parts of F420 and 100 parts of F520), 40 parts of mica powder and 5.8 parts of auxiliary agent (the auxiliary agent comprises 5 parts of BYK161 dispersant, 0.5 part of BYK141 defoamer and 0.3 part of BYK310 flatting agent) are mixed and uniformly stirred for the second time, the stirring speed for the second time is 500 r/min, the stirring time is 60 min, grinding and dispersing are carried out, the particle size of zirconium beads used in the grinding and dispersing process is 0.5mm, the rotating speed is 2000 r/min, and the grinding times are 5 times, so that a component B is obtained;

Example 3: preparation of the coating

A preparation method of a waterproof coating comprises the following steps:

230 parts of polyaspartic acid ester resin (80 parts of NH1420 and 150 parts of NH1520), 100 parts of mica powder and 5.3 parts of auxiliary agent (the auxiliary agent comprises 5 parts of BZ203 dispersant, 0.5 part of TEGO Airex932 antifoaming agent and 0.3 part of auxiliary agent)

Resin leveling agent) and stirring uniformly for the second time, wherein the stirring speed for the second time is 500 r/min, the stirring time is 60 min, grinding and dispersing are carried out, the particle size of zirconium beads used in the grinding and dispersing process is 0.5mm, the rotating speed is 2000 r/min, and the grinding times are 5 times, so as to obtain a component B;

Example 4: preparation of the coating

A preparation method of a waterproof coating comprises the following steps:

mixing 3 parts of graphene and 97 parts of IPDI, uniformly stirring for the first time at a stirring speed of 500 revolutions per minute for 10 minutes, and then homogenizing and dispersing for 5 times under 100MPa pressure to obtain a component A;

mixing 200 parts of polyaspartic acid ester resin (100 parts of NH1420, and the other 100 parts of NH1520), 30 parts of mica powder and 4.8 parts of auxiliary agent (the auxiliary agent comprises 4 parts of AKN2276 dispersing agent, 0.5 part of Rhodoline DF6002 defoaming agent and 0.3 part of Levelolp 410 flatting agent), uniformly stirring for the second time, wherein the stirring speed for the second time is 500 revolutions per minute, the stirring time is 60 minutes, grinding and dispersing are carried out, the particle size of zirconium beads used in the grinding and dispersing process is 0.5mm, the rotating speed is 2000 revolutions per minute, and the grinding times are 5 times, so as to obtain a component B;

Comparative example 1

Compared with example 1, the preparation of component A in comparative example 1 does not include a homogeneous dispersion process, and the rest of the components and the preparation process are the same as example 1.

Comparative example 2

Compared with example 1, in comparative example 2, graphene is not added in the preparation process of component a, and the rest of the components and the preparation process are the same as example 1.

Comparative example 3

Compared with example 1, the volume ratio of component A to component B in comparative example 3 is 1:4, and the rest of the components and the preparation process are the same as example 1. The coating prepared in comparative example 3 failed to cure to a film and was in a fluid state.

Product effectiveness testing

The coatings obtained in examples 1 to 4 and comparative examples 1 to 2 were used to test the water repellency (i.e., water permeability when held under a water pressure of 0.4MPa for 2 hours, and water absorption of the coating was observed), tensile strength, hardness, abrasion resistance (i.e., the mass of the coating lost when rotated 500 revolutions under a pressure of 750 g), impact resistance, and sheet resistance of the coating according to the standards, and the results are shown in Table 1.

Table 1: results of coating Performance testing

As can be seen from Table 1, the coatings obtained in examples 1 to 4 of the present invention formed coatings having good water-repellent properties, tensile strength, hardness, abrasion resistance, impact resistance and antistatic properties, as compared with comparative examples 1 to 2. The coatings prepared in comparative examples 1-2 formed coatings with too high water absorption, and the water-proof properties were relatively poor.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.

Claims

1. The coating is characterized by comprising a component A and a component B;

the component A comprises: graphene and a curing agent;

the component B comprises: resin, filler and auxiliary agent;

the volume ratio of the component A to the component B is 1 (1-3.5);

the resin contains-NH-.

2. The coating of claim 1, wherein the curing agent has a viscosity of less than 600cps at 25 ℃; preferably, the curing agent is at least one selected from hexamethylene diisocyanate trimer, isophorone diisocyanate or diphenylmethane diisocyanate.

3. The coating of claim 1, wherein the graphene has a particle size of 1 μ ι η to 50 μ ι η; the mass ratio of the graphene to the curing agent is (1-10): (90-99).

4. The coating of claim 1, wherein the resin is a polyaspartate resin and/or a polyureaurethane resin.

5. The coating of claim 1, wherein the adjuvant comprises at least one of a defoamer, a leveling agent, or a dispersant.

6. The coating of claim 1, wherein the mass ratio of the resin, the filler and the auxiliary agent is (40-95): (3-50): (0.5-8).

7. A method of preparing a coating according to any one of claims 1 to 6, comprising the steps of:

mixing graphene and a curing agent, stirring for the first time, and homogenizing and dispersing to obtain a component A;

mixing the resin, the filler and the auxiliary agent, stirring for the second time, and grinding and dispersing to obtain a component B;

and mixing the component A and the component B, and stirring for the third time to obtain the coating.

8. The method according to claim 7, wherein the pressure for the homogeneous dispersion is 95 to 110 MPa.

9. The method as claimed in claim 7, wherein the first stirring speed is 450-1400 rpm, and the stirring time is 10-40 min; the second stirring speed is 500-1200 r/min, and the stirring time is 30-150 min; the third stirring speed is 200-550 revolutions per minute, and the stirring time is 5-15 minutes; the grinding dispersion is grinding dispersion by a sand mill, the particle diameter of zirconium beads used in the grinding dispersion process is 0.1-2mm, and the rotating speed is 2000-2800 r/min.

10. Use of a coating according to any one of claims 1 to 6 for waterproofing a house.