TW202016350A - A high-adhesive anti-aging nano-coating and a preparation method thereof - Google Patents

Abstract

The invention provides a high-adhesive anti-aging nano-coating and a preparation method thereof, the substrate is exposed to a monomer vapor atmosphere, and a chemical reaction is formed on the surface of the substrate by plasma discharge to form a protective coating. The monomer vapor is vaporized monomer 1, and/or monomer 2 and/or monomer 3, all of which have their specific structure. The coating obtained by the method of the present application not only achieves good UV aging resistance, but also achieves good adhesion.

Description

High-adhesion aging-resistant nano-coating and preparation method thereof

The invention relates to the technical field of plasma chemical vapor deposition, in particular to a high-adhesion aging-resistant nano protective coating and a preparation method thereof.

Fluorinated olefin polymers have excellent chemical stability, electrical insulation, self-lubricity, non-combustibility, aging resistance, UV resistance, etc., and are widely used in military and daily life. For example, PTFE is one of the best corrosion-resistant materials in the world today, and is known as the "plastic king". Teflon products such as Teflon seals, gaskets, and gaskets have played a pivotal role in the national economy such as chemicals, machinery, electronics, electrical appliances, military industry, aerospace, environmental protection, and bridges. However, the surface energy of commonly used fluorocarbon materials is generally very low, resulting in poor wetting properties between the materials, which cannot be well bonded to the substrate chemically. The adsorption on the substrate surface mainly depends on the intermolecular van der Waals force. Moreover, due to the highly symmetrical structure of the fluorocarbon material and low molecular structure polarity, the van der Waals force cannot form a strong orientation force and an inducing force, but only forms a weak dispersion force, so that the coating is easily peeled off from the surface of the substrate. The current solution is mainly to modify the surface and synthesize new adhesives, surface modification methods such as chemical treatment, high temperature melting, radiation grafting, etc.; the synthesis of new adhesives such as the development of new epoxy resin adhesives, fluorine-containing polymerization Adhesives, etc. The former often requires the use of special energy-intensive special processes; the latter is more difficult to develop new adhesives, and the use of the adhesive often also brings a significant cost increase to the enterprise. In addition, these two methods are not suitable for the process of preparing nano-scale coatings by plasma vapor deposition. The plasma vapor deposition method generally needs to perform surface cleaning and plasma etching treatment on the substrate in advance, and then directly deposit the fluorocarbon material on the surface of the substrate to form a nanometer-thick coating. How to achieve the protection of the chemical inertness and anti-ultraviolet protection of fluorine-containing olefin polymers through the adjustment of molecular structure and the combination of different functional coatings, while ensuring sufficient bonding between the coating and the substrate, is currently the plasma One of the important directions of bulk nano-coating research.

The purpose of the present invention is to provide a high-adhesion aging-resistant nano-coating and a preparation method thereof to solve the problems of poor adhesion between the coating and the surface of the substrate and easy peeling.

The present invention is achieved through the following technical solutions:

A high-adhesion aging-resistant nano-coating, which exposes the substrate to the atmosphere of monomer vapor, and forms a protective coating by plasma discharge on the surface of the substrate;

The monomer vapor is vaporized monomer 1 and/or monomer 2 and/or monomer 3; that is, the monomer vapor includes one of vaporized monomer 1, monomer 2 and monomer 3 Or several types, the "several types" refer to any two types of monomers or three types of monomers; several kinds of gases can be passed in separately or simultaneously, or any two types of monomers can be passed in first and then in The third monomer;

（I）The monomer 1 has the structure represented by formula (I):

(I)

（II）The monomer 2 has a structure represented by formula (II):

(II)

（III）The monomer 3 has a structure represented by formula (III):

(III)

Among them, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , and R ¹³ are groups connected to the double bond. It is independently selected from hydrophobic groups such as hydrogen, alkyl, aryl, halogen, haloalkyl or haloaryl.

m is an integer of 0-5, n is an integer of 1-20, j and k are integers of 0-10 and cannot be 0 at the same time.

R ¹⁴ is a bridging group in the middle of divinyl ether, including polar groups and non-polar groups, specifically, may be a bond, -CO-, -COO-, -O-, arylene, alicyclic Alkylene or hydroxy substituted fatty alkyl subunits.

When the group on the unsaturated bond is H or a short carbon chain alkyl, the deposition rate of the film can be increased; the presence of fluorine substituents can improve the hydrophobic performance of the film.

Preferably, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ^{13 are} independently selected from hydrogen, methyl or fluorine.

A suitable number of fluorinated alkyl carbon atoms can ensure that the melting point and boiling point of the monomer are within an appropriate range, and the monomer is easily vaporized into the vacuum reaction chamber.

Preferably, m is an integer of 0-2, and n is an integer of 1-8. j and k are integers of 1-4, respectively.

The cyclic structure is beneficial for reducing the crystallinity of the polymer, and containing hydroxyl groups is advantageous for improving the adhesion between the coating and the substrate. Preferably, R ¹⁴ may be a bond, an alicyclic alkylene subunit or a hydroxy substituted fatty alkyl subunit .

Preferably, the monomer 1 is a liquid at normal temperature and pressure; and/or the monomer 3 is a liquid at normal temperature and pressure.

Preferably, monomer 2 is a short carbon chain fluorinated olefin, which is a gas at normal temperature and pressure.

The coating protects the surfaces of different substrates against aging and hydrophobicity. The substrates may be solid materials such as metals, optical instruments, clothing fabrics, electronic devices, and medical devices.

In addition, the present invention also discloses a method for preparing the above nano-coating, including the following steps:

(1) Place the substrate in the reaction chamber of the plasma chamber, the vacuum degree in the reaction chamber is 0.1-1000 mTorr;

(2) Pass the plasma source gas to start the plasma discharge for deposition; pass the monomer vapor into the reaction chamber for chemical vapor deposition;

(3) Turn off the plasma discharge for deposition, pass clean compressed air or inert gas, return to normal pressure, open the reaction chamber, and take out the substrate.

Preferably, the monomer vapor includes monomer 1, monomer 2 and monomer 3;

The steam of the monomer 1, the monomer 2 and the monomer 3 respectively pass into the reaction chamber successively;

Or, the steam of the monomer 1, the monomer 2 and the monomer 3 are simultaneously passed into the reaction chamber;

Alternatively, firstly, any two of the monomer 1, the monomer 2 and the monomer 3 are simultaneously passed into the reaction chamber, and then the third monomer of the monomer 1, the monomer 2 and the monomer 3 are passed Into the reaction chamber.

That is, the steam of monomer 1, monomer 2, and monomer 3 can be introduced separately, or simultaneously, or any two types of monomers, and then the third type of monomer, because monomer 2 It is a gas, which can also pass directly into the reaction chamber.

Preferably, the monomer vapor includes at least monomer 1; the mole percentage of monomer 1 in the total flux of the monomer vapor is not less than 20%. When the monomer vapor introduced contains monomer 1, monomer 1 accounts for not less than 20% of the total monomer vapor flux, and monomer 2 and monomer 3 may not be introduced.

Preferably, the volume of the reaction chamber of the plasma chamber is 50-1000L.

Preferably, in step (2), the temperature of the reaction chamber of the plasma chamber is controlled at 30-60°C; the flow rate of the plasma source gas is 5-300 sccm.

Preferably, in step (3), the monomer vapor is introduced into the reaction chamber at 0.1-1000 mTorr, and the flow rate of the monomer vapor is 10-1000 µL/min;

Preferably, in the step (2), after passing the plasma source gas and before the plasma discharge for deposition, a plasma discharge step for pretreatment of the substrate is further included.

In step (2), after the plasma source gas is introduced, the substrate is subjected to plasma discharge pretreatment. After the pretreatment phase ends, it enters the deposition phase (the plasma discharge for pretreatment is converted to plasma discharge for deposition). At this time, the plasma discharge method or parameters may or may not be changed.

Preferably, the plasma discharge (plasma discharge for pretreatment and/or plasma discharge for deposition) is radio frequency discharge, microwave discharge, intermediate frequency discharge, Penning discharge or electric spark discharge.

Preferably, the plasma discharge (pretreatment plasma discharge and/or deposition plasma discharge) is electric spark discharge; plasma discharge frequency is 20Hz-20KHz, pulse width is 5μs-50ms, and discharge time is 100s- 20000s.

Compared with the prior art, the present invention combines the performance of different monomers to construct the structure of the coating. The use of monomers with multiple ether oxygen in the main chain, which generally has a strong binding force with the substrate, improves the adhesion of the coating; the use of fluorine-containing olefin monomer polymer anti-UV properties, improve the coating The ability of the layer to resist ultraviolet aging; the use of a strong hydrophobic coating formed with fluoroalkyl monomers greatly improves the waterproof performance of the composite coating. Moreover, the coating prepared by the method of the present application does not compromise on various properties, and obtains a technical effect that takes into account multiple excellent properties.

Examples 1

In the preparation method of the high-adhesion and anti-aging nano-coating of the invention, the following steps are performed:

(1) Place the PCB board of the electronic device in the 1000L plasma vacuum reaction chamber, and continuously evacuate the reaction chamber to achieve a vacuum of 30 mTorr.

(2) Inject nitrogen gas with a flow rate of 20 sccm. Turn on the EDM plasma discharge to pretreat the PCB board (that is, turn on the EDM type pretreatment plasma discharge). The discharge frequency in the pretreatment stage is 500 Hz and the pulse width is 200 μs. , The discharge time is 100s.

(3) The monomer 3a is introduced first, and then the monomer 2a is introduced, and finally the monomer 1a is introduced, and chemical vapor deposition is performed on the surface of the substrate to prepare a nano-coating. The flow rate of the three monomers in the coating preparation process is 150 μL/min, the inflow time is 500 s, 200 s and 300 s, respectively. The plasma discharge for pretreatment is converted to the plasma discharge for deposition, and the discharge time for the electrical discharge in this deposition stage is 1000 s.

(4) After the coating preparation is completed, the compressed air is introduced to restore the reaction chamber to normal pressure, the chamber is opened, and the PCB of the electronic device is taken out.

Monomer 1a

Monomer 2a

Monomer 3a

Among them, the device for plasma discharge for pretreatment and the device for plasma discharge for deposition may be one set or two separate devices. The plasma discharge device (for example, electrode) for pretreatment is preferably arranged in the reaction chamber and around the base material, so as to facilitate the quick connection with the coating process after pretreatment; the plasma discharge device for deposition can be arranged in the reaction chamber It is installed outside and away from the reaction chamber, so as to avoid the negative influence of the plasma discharge on the substrate during the coating process selectively or as far as possible.

Examples 2

In the preparation method of the high-adhesion and anti-aging nano-coating of the invention, the following steps are performed:

(1) Place the rear-view lens of the car in the 200L plasma vacuum reaction chamber, and continuously evacuate the reaction chamber to achieve a vacuum of 5 mTorr.

(2) Introduce argon gas with a flow rate of 50 sccm, and start the spark plasma discharge for pretreatment (that is, start the spark discharge pretreatment plasma discharge), the discharge frequency in the pretreatment stage is 1000 Hz, the pulse width is 20 μs, and the discharge The time is 100s.

(3) The monomer 3b is introduced first, then the monomer 2b is introduced, and finally the monomer 1a is introduced, and chemical vapor deposition is performed on the surface of the substrate to prepare a nano-coating. The flow rate of the three monomers in the coating preparation process is 150 μL/min, the lead-in time is 500 s, 500 s, and 500 s, respectively. The plasma discharge for pretreatment is converted to the plasma discharge for deposition, and the discharge time in this deposition stage is 1500 s.

(4) After the preparation of the coating is completed, compressed air is introduced to restore the reaction chamber to normal pressure, the chamber is opened, and the rear view lens of the automobile is taken out.

Monomer 1b

Monomer 2b

Monomer 3b

Examples 3

In the preparation method of the high-adhesion and anti-aging nano-coating of the invention, the following steps are performed:

(1) Place the magnesium alloy in the 2000L plasma vacuum reaction chamber, and continuously evacuate the reaction chamber to achieve a vacuum of 100 mtorr.

(2) Introduce argon gas with a flow rate of 10 sccm, and start EDM plasma discharge for pretreatment (that is, start EDM-type plasma discharge for pretreatment). The discharge frequency in the pretreatment phase is 50 kHz, the pulse width is 50 μs, and the discharge The time is 100s.

(3) The monomer 3c is introduced first, and then the monomer 2c and the monomer 1c are simultaneously introduced, and chemical vapor deposition is performed on the surface of the substrate to prepare a nano-coating. The flow rate of the three monomers in the coating preparation process is 200 μL/min, the lead-in time is 1500s and 2500s (2c and 1c), respectively, and the plasma discharge for pretreatment is adjusted to the plasma discharge for deposition. The discharge time of this deposition stage is 4000s.

(4) After the preparation of the coating is completed, compressed air is introduced to restore the reaction chamber to normal pressure, the chamber is opened, and the magnesium alloy is taken out.

Monomer 1c

單體2c

Monomer 2c

Monomer 3c

Examples 4

In the preparation method of the high-adhesion and anti-aging nano-coating of the present invention, the following steps are performed:

(1) Place the rear-view lens of the car in the 1800L plasma vacuum reaction chamber, and continuously evacuate the reaction chamber to achieve a vacuum of 50 mtorr.

(2) Introduce argon gas with a flow rate of 40 sccm. Turn on the EDM plasma discharge for pretreatment (that is, turn on the EDM type pretreatment plasma discharge). The discharge frequency in the pretreatment stage is 2000 Hz, the pulse width is 80 μs, and the discharge The time is 200s.

(3) The monomer 3d is introduced first, then the monomer 2d is introduced, and the monomer 1d is finally introduced, and chemical vapor deposition is performed on the surface of the substrate to prepare a nano-coating. The flow rate of the three monomers in the preparation process of the coating is 200 μL/min, the passing time is 500 s, 500 s and 800 s, respectively. The plasma discharge for pretreatment is adjusted to the plasma discharge for deposition. The discharge time in the deposition stage is 1800s.

(4) After the preparation of the coating is completed, compressed air is introduced to restore the reaction chamber to normal pressure, the chamber is opened, and the rear view lens of the automobile is taken out.

Monomer 1d

Monolithic 2d

Monolithic 3d

Examples 5

In the preparation method of the high-adhesion and anti-aging nano-coating of the present invention, the following steps are performed:

(1) Place the heat preservation cup in the 3500L plasma vacuum reaction chamber, and continuously evacuate the reaction chamber to achieve a vacuum of 200 mtorr.

(2) Introduce argon gas with a flow rate of 10 sccm, and start EDM plasma discharge for pretreatment (that is, start EDM-type plasma discharge for pretreatment), the discharge frequency in the pretreatment stage is 50 kHz, the pulse width is 80 μs, and the discharge The time is 200s.

(3) The monomer 3e is introduced first, and then the monomer 2e and the monomer 1e are simultaneously introduced, and chemical vapor deposition is performed on the surface of the substrate to prepare a nano-coating. The flow rate of the three monomers during the preparation of the coating is 250 μL/min, the lead-in time is 2500 s and 2500 s, respectively. The plasma discharge for pretreatment is adjusted to the plasma discharge for deposition. The discharge time in the deposition stage is 5000s.

(4) After the preparation of the coating is completed, compressed air is introduced to restore the reaction chamber to normal pressure, the chamber is opened, and the insulated cup is taken out.

Monomer 1e

Monomer 2e

單體3e

Monomer 3e

Examples 6

Compared with Example 1, the flow rate of the three monomers in step (3) was changed to 200 μL/min, and other conditions were unchanged.

Examples 7

Compared with Example 1, in step (3), the three monomers are replaced with 1000s, 800s, and 900s, and the discharge time is correspondingly replaced with 2700s, and other conditions remain unchanged.

Examples 8

Compared with Example 7, the reaction chamber in step (1) was continuously evacuated to a vacuum of 10 mTorr, and other conditions remained unchanged.

Examples 9

Compared with Example 7, the discharge frequency of the spark plasma in step (2) was changed to 1000 Hz, and other conditions remained unchanged.

Examples 10

Compared with Example 7, in step (3), monomer 1a is not passed, and other conditions remain unchanged.

Examples 11

Compared with Example 7, in the step (3), the monomers 2a and 3a are not introduced, the monomer 1a introduction time is 2700s, the discharge time is also 2700s, and other conditions remain unchanged.

Examples 12

Compared with Example 7, in the step (3), the monomers 1a and 3a are not fed, the monomer 2a is introduced for 2700s, the discharge time is also 2700s, and other conditions remain unchanged.

Examples 13

Compared with Example 7, in the step (3), the monomers 1a and 2a are not introduced, the monomer 3a introduction time is 2700s, the discharge time is also 2700s, and other conditions remain unchanged.

Examples 14

Compared with Example 3, in step (3), the monomer 3c is not fed, and the monomer 2c and 1c are simultaneously fed for 4000s, and the discharge time is also 4000s, and other conditions remain unchanged.

The substrate after plating in the above embodiments is subjected to coating thickness, water contact angle, xenon lamp aging test, ultraviolet aging test, and adhesion test.

The thickness of the nano-coating is tested using the US Filmetrics F20-UV-film thickness measuring instrument.

Nano-coating water contact angle, tested according to GB/T 30447-2013 standard.

Xenon lamp aging test is tested according to GB/T 16422.2-2014 standard.

The UV aging test is tested according to the GB/T 16422.3-2014 standard.

Adhesion test method, according to GB/T 9286-1998 standard for 100 grid knife scratch test.

Table 1

With the technology of the present invention, a nano-coating with multiple protective properties can be obtained. In order to obtain multi-functional coatings by conventional technical means, the coatings with different functions are mainly superimposed to make the thickness more than tens of hundreds of microns, which often leads to the signal transmission, electrical conductivity and thermal conductivity of some electronic devices becoming very difference. In contrast, nano-coatings have almost no effect on the above properties due to their thickness at the nanoscale. Using plasma to deposit coating materials with different functions at the same time solves the disadvantage of poor adhesion between coatings.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than limiting it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or replacements do not deviate from the essence of the corresponding technical solutions of the technical solutions of the embodiments of the present invention. range.

no

no

Claims (14)

A high-adhesion aging-resistant nano-coating, which exposes the substrate to the atmosphere of monomer vapor and forms a protective coating by plasma discharge on the surface of the substrate; the monomer vapor is vaporized monomer 1. And/or monomer 2, and/or monomer 3; the monomer 1 has the structure represented by formula (I):

(I) The monomer 2 has the structure represented by formula (II):

(II) The monomer 3 has a structure represented by formula (III):

(III) where R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ^{13 are} independently selected from hydrogen, alkyl Radical, aryl, halogen, haloalkyl or haloaryl; m is an integer of 0-5, n is an integer of 1-20, j and k are integers of 0-10 and cannot be 0 at the same time; R ¹⁴ is A bond, -CO-, -COO-, arylene, alicyclic alkylene or hydroxy substituted fatty alkyl subunit. The nano-coating according to item 1 of the patent application scope, characterized in that R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² and R ^{13 are} independently selected from hydrogen, methyl or fluorine. The nanocoating according to item 1 of the patent application range, wherein m is an integer of 0-2, n is an integer of 1-8, and j and k are integers of 1-4, respectively. A method for preparing a nano-coating according to item 1 of the patent application range, wherein R ¹⁴ is a bond, an alicyclic alkylene subunit, or a hydroxy substituted fatty alkyl subunit. The method for preparing a nano-coating according to item 1 of the patent application range, wherein the monomer 1 is a liquid at normal temperature and pressure and/or the monomer 3 is a liquid at normal temperature and pressure, and/or Or monomer 2 is a gas at normal temperature and pressure. The nanocoating according to item 1 of the patent application range, wherein the substrate is metal, optical instruments, clothing fabrics, electronic devices, or medical devices. A method for preparing a high-adhesion and aging-resistant nano-coating according to any one of patent application items 1 to 6, characterized in that it includes the following steps: (1) Place the substrate in the reaction chamber of the plasma chamber, the vacuum degree in the reaction chamber is 0.1-1000 mTorr; (2) Inject the plasma source gas, start the plasma discharge for deposition, and pass the monomer vapor into the reaction chamber for chemical vapor deposition; (3) Turn off the plasma discharge for deposition, pass clean compressed air or inert gas, return to normal pressure, open the reaction chamber, and take out the substrate. The method for preparing a nano-coating according to item 7 of the patent application range, wherein the monomer vapor includes monomer 1, monomer 2 and monomer 3; The steam of the monomer 1, the monomer 2 and the monomer 3 respectively pass into the reaction chamber successively; Or, the steam of the monomer 1, the monomer 2 and the monomer 3 are simultaneously passed into the reaction chamber; Alternatively, firstly, any two of the monomer 1, the monomer 2 and the monomer 3 are simultaneously passed into the reaction chamber, and then the third monomer of the monomer 1, the monomer 2 and the monomer 3 are passed Into the reaction chamber. The method for preparing a nano-coating according to item 7 or 8 of the patent application range, wherein the monomer vapor includes at least monomer 1; monomer 1 accounts for the total flux of the monomer vapor The mole percentage is not less than 20%. The method for preparing a nano-coated layer according to item 7 of the patent application range, characterized in that, in step (2), the temperature of the reaction chamber of the plasma chamber is controlled at 30-60°C; The flow rate of the plasma source gas passed into the reaction chamber is 5-300 sccm. The method for preparing a nano-coating according to item 7 of the patent application range, wherein the monomer vapor includes monomer 1 and/or monomer 3; In step (3), the feed pump is used to atomize and volatilize monomer 1 and/or monomer 3 into the reaction chamber; The monomer vapor is introduced into the reaction chamber at a pressure of 0.1-1000 mTorr; The flow rate of the monomer vapor into the reaction chamber is 10-1000 µL/min. The method for preparing a nano-coating according to item 7 of the patent application range, characterized in that, after passing the plasma source gas and before the plasma discharge for deposition, a pretreatment of the substrate is also included Using plasma discharge process. The method for preparing a nano-coating according to item 7 or item 12 of the patent application range, wherein the plasma discharge method is radio frequency discharge, microwave discharge, intermediate frequency discharge, penning discharge or electric spark discharge. According to the method for preparing a nano-coating described in Item 7 or Item 12 of the patent application range, the plasma discharge is an electric spark discharge; the plasma discharge frequency is 20 Hz-20 KHz, the pulse width is 5 μs-50 ms, and the discharge time is 100s-20000s.