AU2021101178A4

AU2021101178A4 - An optimization method for biomimetic self-healing nano composite coating

Info

Publication number: AU2021101178A4
Application number: AU2021101178A
Authority: AU
Inventors: Ziang Chen; Baohong Hao; Feng He; Jun Hou; Ruohan Ji; Chengyang Li; Hongyu LU; Sijia Wang; Ding Zeng; Tingfeng Zhao
Original assignee: Research Institute of Highway Ministry of Transport; Beijing Institute of Petrochemical Technology
Current assignee: Research Institute of Highway Ministry of Transport; Beijing Institute of Petrochemical Technology
Priority date: 2021-03-05
Filing date: 2021-03-05
Publication date: 2021-05-06
Anticipated expiration: 2029-03-05

Abstract

The invention discloses an optimization method for biomimetic self-healing nano composite coating. First, the nano unit in the nano composite coating is designed to control the spatial distribution parameters of the multi-component nano particles that meet the requirements of isomorphous substitution and intercalation; Introducing magnetic chiral molecules into nanoparticles, designing nanoparticles as hand-shaped asymmetric structural molecular models, so that the palm surface that is magnetically attracted has a gecko foot bristles spicule structure, and the back of the hand has a micro-nano structure of lotus leaf papillae; Coating and pre-treating the nanoparticles with a combination of multiple surfactants, so that the nanoparticles are uniformly dispersed in the composite coating; Introduce nano particles of smaller particle size as a quasi-fluid state reserve, making them a backbone particle with bionic self-repairing properties for microcracks. This method can self-repair the micro cracks and inhibit the rapid expansion of the micro cracks during the load-bearing process, thereby improving the corrosion resistance and durability of the coated steel components.

Description

An optimization method for biomimetic self-healing nano composite

coating

TECHNICAL FIELD

The invention relates to the technical field of anti-corrosion coatings, in particular to

an optimization method for biomimetic self-healing nano composite coating.

BACKGROUND

April 24th every year is designated as "World Corrosion Day". According to statistics,

the amount of metals scrapped and lost by corrosion in the world is 100 million tons every

year, accounting for 20% ~ 40% of the annual output of steel. The annual corrosion loss in

China is as high as 2.1278 trillion RMB (about 310 billion US dollars), accounting for

3.34% of the national GDP, which is close to the level that the world average corrosion

loss accounts for about 3.4% of the global gross national product (GNP). This is only a

direct loss, and the indirect loss is even more serious. The leakage, spilling, dripping and

seepage of energy caused by equipment corrosion damage can also cause secondary

disasters which are incalculable. It can be seen that corrosion has become one of the

important factors that seriously affect the sustainable development of national economy

and society.

Anti-corrosion coating is the first line of defense to prevent corrosive medium from

entering metal surface, and it is also an important tool for human to deal with corrosion. At

present, the service life of common epoxy coatings widely used is only about 10 ~ 15 years,

and that of long-acting nano-composite coatings is only about 15 ~ 25 years, while the

future development needs durability of 25 ~ 50 years or even higher. Coatings in the prior art can't meet the requirements of future development from durability life. In addition, existing coatings have bottleneck problems such as weak binding force, poor deformation coordination, easy cracking, etc., and can't meet the increasingly high "three defenses" requirements of "rust prevention, pollution prevention and crack prevention" and the "three highs" requirements of "high dispersion of nanoparticles, high coordination with matrix and high durability of coatings" under the new situation.

SUMMARY

The purpose of the invention is to provide a method for constructing functional groups

of a bionic self-repairing nano composite coating, which can carry out self-repairing on

micro cracks, inhibit the rapid expansion of micro cracks in the bearing process, and

improve the corrosion resistance and durability of coated steel members.

The purpose of the invention is realized by the following technical scheme:

The invention relates to an optimization method for biomimetic self-healing nano

composite coating, which comprises the following steps:

Step 1. Design nano-units in the nano-composite coating, control the spatial

distribution parameters of multi-component nanoparticles that meet the requirements of

isomorphous substitution and intercalation to form optimized secondary nanopolymer

morphology on the crystal plane;

Step 2. Introduce magnetic chiral molecules into the nanoparticles, design the

nanoparticles as a hand-shaped asymmetric structural molecular model, so that the palm

surface that is magnetically attracted has the gecko foot bristles spicule structure, and the

back of the hand has the lotus leaf papillary micro nanometer structure;

Step 3. Coating and pre-treating the nanoparticles with a combination of multiple

surfactants, so that the nanoparticles are uniformly dispersed in the composite coating

without agglomeration;

Step 4. Introduce nanoparticles of smaller particle size as quasi-fluid storage, making

them the backbone particles with bionic self-repairing characteristics for micro-cracks,

repair the formation of small cracks in the coating of the component and prevent the

cracks's expansion;

Step 5. Introduce an appropriate amount of epoxy resin adhesive to further enhance

the adhesion and deformation synergy between the modified epoxy resin paint and the base

material, and strengthen the gecko effect.

It can be seen from the technical scheme provided by the present invention that the

nanocomposite coating optimized by the above method can overcome the bottleneck

problems existing in the existing coating, such as weak binding force, poor deformation

coordination, easy cracking, etc., so as to meet the "three imitations" requirements of "lotus

leaf imitation, gecko foot imitation, bionic self-repair" and the "three highs" of "high

dispersion of nanoparticles, high coordination with matrix and high durability of coating

itself', which are increasingly high under the new situation. It is of great significance to

promote the interdisciplinary development of nanocoatings and the construction of

engineering safety.

BRIEF DESCRIPTION OF THE FIGURES

Fig. 1 is the schematic diagram of the optimization method of the bionic self repairing

nano composite coating provided by the embodiment of the invention;

Fig. 2 is the schematic diagram of the hand asymmetric structure and gecko foot

dynamic adsorption desorption provided by the embodiment of the invention;

Fig. 3 is the schematic diagram of self zipper repair for micro cracks in the

embodiment of the invention.

DESCRIPTION OF THE INVENTION

The following is a clear and complete description of the technical solutions in the

embodiments of the invention in combination with the drawings in the embodiments of the

invention. Obviously, the described embodiments are only part of the embodiments of the

invention, not all of them. Based on the embodiment of the invention, all other

embodiments obtained by ordinary technicians in the art without making creative work

belong to the protection scope of the invention.

The embodiment of the present invention will be described in further detail with

reference to the attached drawings. As shown in Figure 1, a schematic diagram of the

optimization method of bionic self-repairing nano composite coating provided by the

embodiment of the present invention, and the method includes the following steps:

Step 1. Design nano-units in the nano-composite coating, control the spatial

isomorphous substitution and intercalation, and form optimized secondary nano-polymer

morphology on the crystal plane.

In this step, the new carbon nanotubes and graphene are introduced into the ordinary

zinc-rich epoxy resin, and the unique molecular structure matrix is used to strengthen the

uniform dispersion and pinning of the nanoparticles.

In specific implementation, the introduced common zinc-rich epoxy resin includes

%-70% epoxy resin and 8% zinc powder.

And the introduced nanounits include 1% carbon nanotubes and 1% graphene.

Step 2. Introduce magnetic chiral molecules into the nanoparticles, design the

back of the hand has the lotus leaf papillary micro nanometer structure.

In specific implementation, the introduced magnetic chiral molecule isV-iron trioxide

with the mass percentage of 4% on the order of 10 nm.

Through the design of the above structure, the "gecko foot dynamic adsorption

desorption effect" and the "lotus leaf super-sparse effect" can be presented. Figure 2 is a

schematic diagram of the hand-shaped asymmetric structure and the dynamic adsorption

desorption of the gecko foot provided by the embodiment of the present invention: With

the structure in Figure 2, on the one hand, it forms a gecko-like firm and dynamic adhesive

bond with the components; on the other hand, it forms a lotus-like self-cleaning super

isolation with the medium. At the same time, with the aid of the gecko's dynamic

adsorption-desorption characteristics, the deformation coordination problem of the coating

under the alternating load can be solved, and the phenomenon of "layer peeling" can be

prevented in the actual application process. This fundamentally improves the weather

resistance and durability of the nanocomposite coating.

Step 3. Use a combination of multiple surfactants to pre-treat the nanoparticles, so that

the nanoparticles are uniformly dispersed in the composite coating without agglomeration.

In this step, the multiple surfactants include 1.0% PAA, 1.2%

cetyltrimethylammonium bromide, 1.4% sodium dodecylbenzene sulfonate, 1.6% by mass.

Sodium lauryl sulfate, 4% dispersant.

Step 4. Introduce nano particles of smaller particle size as quasi-fluid storage, making

them into backbone particles with bionic self-repairing characteristics for micro-cracks,

cracks's expansion.

Through this step, a relatively stable self-repairing functional group structure can be

built, which has a molecular filling effect.

In this step, when microcracks appear in the nanocomposite coating, the wound can

be healed spontaneously like a zipper. Figure 3 is a schematic diagram of the self-zipper

type repair of microcracks according to the embodiment of the present invention, refer to

Figure 3: Biomimetic self-healing functional groups can be constructed by relying on the

chiral reversible double bond of chiral particles. When micro cracks appear in the coating,

the double bond can be quickly opened to bridge, and then the "domino " effect is produced.

Fill the tiny crack gap, repair and block the formation and expansion of the tiny crack in

the component coating, heal the wound like a zipper.

In the specific implementation, the introduced nanoparticles include about 2% of

titanium dioxide with the order of 20nm, about 2% of aluminum oxide with the order of

nm, and about 5% of zinc oxide with the order of 30nm. In this way, a certain particle

size gradient is formed, added simultaneously, and a reversible double bond with a bond

angle of 120° is constructed to realize the bridging of micro cracks..

materia to strengthen the gecko effect.

It is worth noting that what is not described in detail in the embodiments of the present

invention belongs to the prior art known to the skilled person in the field, and the term

"about" related to numerical values in the whole specification and claims refers to an

interval with certain accuracy which is familiar and acceptable to the skilled person, and

the interval is%.

To sum up, the nano-composite coating optimized by this method can have two

functions: (1 Dynamic "adsorption-desorption" bonding can be formed when the

substrates are bonded, which not only enhances the adhesion, but also avoids the formation

quickly open the double bonds for bridging, and the micro-cracks can be self-repaired in

Domino and Zipper mode by using the small-size "quasi-fluid" characteristics of

nanoparticles.

The above is only a preferred embodiment of the present invention, but the protection

scope of the present invention is not limited to this. Any change or substitution that can be

easily thought of by any person familiar with the technical field within the technical scope

disclosed by the present invention should be covered within the protection scope of the

present invention. Therefore, the protection scope of the present invention should be

subject to the protection scope of the claims.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. An optimization method of bionic self-repairing nano composite coating,

characterized by comprising the following steps:

Step 1. Design nano-units in the nano-composite coating, control the spatial

isomorphous substitution and intercalation to form optimized secondary nano-polymer

morphology on the crystal plane;

Step 2. Introduce magnetic chiral molecules into the nanoparticles, design the

back of the hand has the lotus leaf papillary micro nanometer structure;

without agglomeration;

cracks's expansion;

material, and strengthen the gecko effect.

2. The optimization method of bionic self-repairing nano-composite coating

according to claim 1 is characterized in that in Step 1, new carbon nanotubes and graphene

are further introduced into common zinc-rich epoxy resin, and the unique molecular

structure matrix thereof is used to enhance the uniform dispersion and pinning of nano

particles.

3. The optimization method of bionic self repairing nano composite coating according

to claim 2, which is characterized in that the introduced ordinary zinc rich epoxy resin

includes 60% - 70% epoxy resin and 8% zinc powder by mass.

4. The introduced nano-units include 1% carbon nanotubes and 1% graphene by mass.

5. The method for optimizing the bionic self-repairing nano composite coating

according to claim 1, which is characterized in that in Step 3, the various surfactants

comprise the following components in percentage by mass.

1.0% PAA, 1.2% cetyltrimethylammonium bromide, 1.4% sodium dodecylbenzene

sulfonate, 1.6% sodium dodecyl sulfate and 4% dispersant.

6. The optimization method for bionic self repairing nano composite coating

according to claim 1, which is characterized in that in step 4, the particle size of the

introduced nano particles has a certain particle size gradient, and specifically includes the

following steps: the mass percentage of the nano particles is as follows:

2% titanium dioxide in the order of 20nm, 2% aluminum oxide in the order of 50nm

and 5% zinc oxide in the order of 30nm.

In this way, a certain particle size gradient is formed, added simultaneously, and a

reversible double bond with a bond angle of 120° is constructed to realize the bridging of

micro cracks.

FIGURES

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Figure 1. The schematic diagram of the optimization method of the bionic self

repairing nano composite coating provided by the embodiment of the invention