CN115073795A - Hydrophobic polymer material surface hydrophilic modification method based on carbon dioxide plasma - Google Patents

Abstract

The invention discloses a method for hydrophilic modification of the surface of a hydrophobic polymer material based on carbon dioxide plasma. The method comprises: step 1: using a high-pressure air plasma spray gun to spray a plasma jet on the surface of the hydrophobic polymer material to obtain The cleaned hydrophobic polymer material; step 2: placing the cleaned hydrophobic polymer material in a plasma processing device, evacuating the plasma processing device, and then introducing the first mixed gas, controlling the gas flow, adjusting the The air pressure in the plasma treatment device, when the air pressure in the plasma treatment device is stable, start the power supply, and perform plasma modification treatment on the surface of the polymer material to obtain a pre-modified material; Step 3: Turn off the power supply of the plasma treatment device , and the pre-modified material is allowed to stand in the plasma treatment device, that is, it is obtained. The surface of the polymer material treated by the method of the invention has good hydrophilicity, and can also realize the activation and reuse of carbon dioxide.

Description

Hydrophilic modification of the surface of a hydrophobic polymer material based on carbon dioxide plasma sexual methods

technical field

The invention relates to the technical field of material modification, in particular to a method for hydrophilic modification of the surface of a hydrophobic polymer material based on carbon dioxide plasma.

Background technique

Plasma surface treatment technology excites gas molecules with a certain energy, dissociates the gas into excited states such as electrons, ions, free radicals and other metastable states, collides with the surface of the material, destroys covalent bonds, generates free radicals, and activates the material. surface. The activated material surface can be combined with the excitation gas to generate chemically active groups on the surface. At present, plasma surface treatment technology is widely used in electroplating, coating and ink industries to increase the bonding force with the substrate. Some researchers have used plasma to modify the bamboo surface by plasma, and found that plasma treatment can effectively reduce the contact angle of the bamboo surface to water, but the contact angle of the surface will slowly recover over time. The applicant has also done research on the encapsulation of plasma technology and found that the plasma can activate the surface of any substance, but the activated groups will annihilate over time. Therefore, in order to obtain a material surface with better hydrophilicity, some researchers use plasma grafting technology to graft a hydrophilic monomer or polymer on the hydrophobic surface after plasma activation, and the obtained material surface has lower contact angle. Han et al. treated feldspar ceramics with steam produced by ionizing triethylene glycol dimethacrylate with atmospheric pressure helium plasma, and the results showed that the surface of the ceramics after plasma jet treatment contained hydroxyl radicals, and the hydrophilicity was improved. .

Carbon dioxide is a very stable molecule that is difficult to excite and then react. Global warming caused by carbon dioxide-based greenhouse gas emissions is a serious threat to human survival and sustainable development, and is one of the major global challenges facing human beings today. At the same time, the task of improving environmental quality in my country is still severe at this stage. In recent years, many studies have focused on the adsorption and energy regeneration of carbon dioxide. Among them, the research on catalytic decomposition of carbon dioxide by plasma technology has become one of the hotspots in carbon dioxide energy research. However, the conversion rate of carbon monoxide or methane is not ideal, and the utilization rate of carbon dioxide is not high. The study found that carbon dioxide is activated as an electron acceptor, and blending carbon dioxide with rare gases such as oxygen or argon can improve the decomposition efficiency of carbon dioxide to a certain extent. After the polymer material is bombarded by ions, it will lose electrons and generate some activated groups, which will also accelerate the decomposition of carbon dioxide and facilitate the covalent bonding of the activated carbon dioxide with the surface of the material, thereby forming a permanent affinity on the surface of the material. water group. The purpose of this application is to activate and reuse carbon dioxide to generate more hydrophilic groups on the surface of the material, thereby reducing the emission of carbon dioxide in the environment.

SUMMARY OF THE INVENTION

The purpose of the present invention is to propose a vacuum plasma surface hydrophilic modification technology in carbon dioxide atmosphere, which utilizes high-frequency electricity to ionize carbon dioxide, which can not only realize the hydrophilic modification of the surface of the hydrophobic polymer film, but also realize the reuse of carbon dioxide, Reduce carbon dioxide emissions.

To achieve the above object, the present invention provides the following technical solutions:

The invention provides a carbon dioxide plasma-based hydrophilic modification method for the surface of a hydrophobic polymer material, which comprises the following steps:

Step 1: use a high-pressure air plasma spray gun to spray the plasma jet on the surface of the hydrophobic polymer material to obtain the cleaned hydrophobic polymer material;

Step 2: place the cleaned hydrophobic polymer material in the plasma processing device, evacuate the plasma processing device, and then introduce the first mixed gas, control the gas flow, and adjust the air pressure in the plasma processing device. After the air pressure in the plasma treatment device is stabilized, the power is turned on, and the surface of the polymer material is subjected to plasma modification treatment to obtain a pre-modified material;

Step 3: Turn off the power supply of the plasma treatment device, and let the pre-modified material stand in the plasma treatment device.

Further, in the second step, the first mixed gas includes carbon dioxide and a second mixed gas, and the volume ratio of the second mixed gas to carbon dioxide is (0-5): (95-100).

Further, the second mixed gas is oxygen or rare gas.

Further, in the second step, vacuuming to a degree of vacuum is 5-10Pa, the time of modification treatment is 3-10min, the pressure of modification treatment is 20-80Pa, and the power of the plasma treatment device is 50-300W .

Further, in the third step, the pre-modified material is placed in the plasma treatment device for a standing time of 30s-3min.

Further, hydrophobic polymer materials include polyethylene, polypropylene, polyesters, and silica gel.

Compared with the prior art, the beneficial effects of the present invention are:

The carbon dioxide plasma-based hydrophilic modification method for the surface of the hydrophobic polymer material of the present invention has good hydrophilicity on the surface of the polymer material treated by the plasma, and is used in the fields of super absorbent materials, biomedical materials, oil-water separation and the like . Moreover, the surface hydrophilicity of the modified polymer material is stable, and the contact angle does not change significantly with the passage of time. Compared with the existing plasma surface modification technology, the method does not require polymer monomers, is not easy to produce pollution, and can also realize the activation and reuse of carbon dioxide, thereby reducing the storage of carbon dioxide in the environment. And the modification process of the method has short reaction time and good modification effect.

Description of drawings

Fig. 1 is the effect schematic diagram after modification in embodiment 1;

Fig. 2 is the effect schematic diagram after modification in embodiment 3;

3 is a schematic diagram of the effect after modification in Example 4.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

The invention provides a carbon dioxide plasma-based hydrophilic modification method for the surface of a hydrophobic polymer material, which comprises the following steps:

Step 1: use a high-pressure air plasma spray gun to spray the plasma jet on the surface of the hydrophobic polymer material to obtain the cleaned hydrophobic polymer material;

Step 2: place the cleaned hydrophobic polymer material in the plasma processing device, evacuate the plasma processing device, and then introduce the first mixed gas, control the gas flow, and adjust the air pressure in the plasma processing device. After the air pressure in the plasma treatment device is stabilized, the high-frequency power supply is started to perform plasma modification treatment on the surface of the polymer material to obtain a pre-modified material;

Step 3: Turn off the high-frequency power supply of the plasma treatment device, and let the pre-modified material stand still in the plasma treatment device.

Specifically, in the second step, the first mixed gas includes carbon dioxide and the second mixed gas, and the volume ratio of the second mixed gas to carbon dioxide is (0-5): (95-100).

Specifically, the second mixed gas is oxygen or rare gas.

Specifically, in the second step, the vacuum is evacuated to a degree of vacuum of 5-10Pa, the modification treatment time is 3-10min, the modification treatment pressure is 20-80Pa, and the power of the plasma treatment device is 50-300W .

Specifically, in the third step, the pre-modified material is placed in the plasma treatment device for a standing time of 30s-3min.

Specifically, the hydrophobic polymer material includes polyethylene, polypropylene, polyester, silica gel, rubber and other material films, rod-shaped or three-dimensional materials.

Example 1

This embodiment discloses a carbon dioxide plasma-based method for hydrophilic modification of the surface of a hydrophobic polymer material, including the following steps:

S1: Place the polypropylene spunbond non-woven fabric on the operating table, use a high-pressure atmospheric plasma spray gun that can move two-dimensionally at a speed of 5 m/min, and spray the plasma jet on the surface of the polypropylene spunbond non-woven fabric. The voltage is 200V and the discharge frequency is 15kHz, and the polypropylene spunbond non-woven fabric is cleaned.

S2: Place the cleaned polypropylene spunbond non-woven fabric in a plasma treatment device, pump the plasma treatment device to a vacuum of 5Pa, introduce CO ₂ gas, and adjust the air pressure in the plasma treatment device to 40Pa. After stabilization, start the high-frequency power supply, the processing power is 300W, and the processing time is 5min.

S3: Turn off the high-frequency power supply, take out the polypropylene spunbond non-woven fabric after 1 min to obtain modified polypropylene, and measure that its contact angle is reduced from 97.5° before treatment to 48.5°. After one month, the contact angle was determined to be 49.9°, as shown in Figure 1.

Example 2

This embodiment discloses a carbon dioxide plasma-based method for hydrophilic modification of the surface of a hydrophobic polymer material, including the following steps:

Place the ultra-high molecular weight polyethylene rod-shaped material on the operating table, use a high-pressure atmospheric plasma spray gun that can move up and down at a speed of 10m/min and rotate at 15 ^o /min, and spray the plasma jet on the ultra-high molecular weight polyethylene rod-shaped material. On the surface, the ultra-high molecular weight polyethylene rod was cleaned at a voltage of 200V and a discharge frequency of 15kHz.

Place the cleaned UHMWPE rod in a plasma treatment device, pump the plasma treatment device to a vacuum of 5Pa, and introduce a mixed gas of _CO2 and _O2 , wherein the volume ratio of _O2 is 5 Pa. %. The air pressure in the plasma processing apparatus was adjusted to 80 Pa. After stabilization, start the high-frequency power supply, the processing power is 250W, and the processing time is 10min.

Turn off the high-frequency power supply, take out the ultra-high molecular weight polyethylene rod after 3 minutes, and obtain the modified ultra-high molecular weight polyethylene rod. After immersing it in water and taking it out, a relatively uniform water film can be obtained, and the droplets will not flow down in strands. .

Example 3

This embodiment discloses a carbon dioxide plasma-based method for hydrophilic modification of the surface of a hydrophobic polymer material, including the following steps:

S1: Put the polyester foam on the operating table, use a high-pressure atmospheric plasma spray gun that can move two-dimensionally at a speed of 5m/min, and spray the plasma jet on the surface of the polyester foam, at a voltage of 200V and a discharge frequency of 15kHz , for cleaning polyester foam.

S2: Place the cleaned polyester foam in a plasma treatment device, pump the plasma treatment device to a vacuum of 7Pa, and pass in a mixed gas of CO ₂ and O ₂ , in which the volume ratio of O ₂ is 2% . The air pressure in the plasma processing apparatus was adjusted to 20 Pa. After stabilization, start the high-frequency power supply, the processing power is 50W, and the processing time is 10min.

S3: Turn off the high-frequency power supply, take out the polyester foam after 3 minutes, and measure that its contact angle is reduced from 90° to 38.4°. After one month, the contact angle was determined to be 37°, as shown in FIG. 2 .

Example 4

This embodiment discloses a carbon dioxide plasma-based method for hydrophilic modification of the surface of a hydrophobic polymer material, including the following steps:

S1: Put the PTFE plate on the operating table, use an atmospheric plasma spray gun that can move two-dimensionally at a speed of 1m/min, and spray the plasma jet on the surface of the PTFE plate at a voltage of 200V , the discharge frequency is 15kHz, and the polyester foam is cleaned.

S2: Place the cleaned polyester foam in a plasma treatment device, pump the plasma treatment device to a vacuum of 5Pa, and introduce a mixed gas of _CO2 and _O2 , in which the volume ratio of _O2 is 1% . The air pressure in the plasma processing apparatus was adjusted to 60 Pa. After stabilization, start the high-frequency power supply, the processing power is 300W, and the processing time is 8min.

S3: Turn off the high-frequency power supply, take out the polyester foam after 3 minutes, and measure that its contact angle is reduced from 103° to 64°. After one month, the contact angle was determined to be 68°, as shown in FIG. 3 .

It will be apparent to those skilled in the art that the present invention is not limited to the details of the above-described exemplary embodiments, but that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments are to be regarded in all respects as illustrative and not restrictive, and the scope of the invention is to be defined by the appended claims rather than the foregoing description, which are therefore intended to fall within the scope of the claims. All changes within the meaning and scope of the equivalents of , are included in the present invention. Any reference signs in the claims shall not be construed as limiting the involved claim.

In addition, it should be understood that although this specification is described in terms of embodiments, not each embodiment only includes an independent technical solution, and this description in the specification is only for the sake of clarity, and those skilled in the art should take the specification as a whole , the technical solutions in each embodiment can also be appropriately combined to form other implementations that can be understood by those skilled in the art.

Claims (6)

1. a hydrophobic polymer material surface hydrophilic modification method based on carbon dioxide plasma, is characterized in that, this method comprises the steps: Step 1: use a high-pressure air plasma spray gun to spray the plasma jet on the surface of the hydrophobic polymer material to obtain the cleaned hydrophobic polymer material; Step 2: place the cleaned hydrophobic polymer material in the plasma processing device, evacuate the plasma processing device, and then introduce the first mixed gas, control the gas flow, and adjust the air pressure in the plasma processing device. After the air pressure in the plasma treatment device is stabilized, the power is turned on, and the surface of the polymer material is subjected to plasma modification treatment to obtain a pre-modified material; Step 3: Turn off the power supply of the plasma treatment device, and let the pre-modified material stand in the plasma treatment device. 2 . The method for hydrophilic modification of the surface of a hydrophobic polymer material based on carbon dioxide plasma according to claim 1 , wherein in the second step, the first mixed gas comprises carbon dioxide and a second mixed gas, and the second mixed gas. 3 . The volume ratio of gas to carbon dioxide is (0-5):(95-100). 3 . The method for hydrophilic modification of the surface of a hydrophobic polymer material based on carbon dioxide plasma according to claim 2 , wherein the second mixed gas is oxygen or a rare gas. 4 . 4. The method for hydrophilic modification of the surface of hydrophobic polymer material based on carbon dioxide plasma according to claim 1, characterized in that, in the step 2, vacuuming to a degree of vacuum is 5-10Pa, and the time of the modification treatment For 3-10min, the pressure of the modification treatment is 20-80Pa, and the power supply of the plasma treatment device is 50-300W. 5 . The method for hydrophilic modification of the surface of hydrophobic polymer materials based on carbon dioxide plasma according to claim 1 , wherein in the step 3, the pre-modified material is placed in the plasma treatment device for a standing time of 30 s. 6 . -3min. 6 . The method for hydrophilic modification of the surface of hydrophobic polymer materials based on carbon dioxide plasma according to claim 1 , wherein the hydrophobic polymer materials comprise polyethylene, polypropylene, polyester, silica gel, and rubber materials. 7 . , the morphology of the hydrophobic polymer material is film, rod-like or three-dimensional structure.

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