CN104846620A - Production method of polyaniline electromagnetic shielding fabrics - Google Patents

Abstract

The invention provides a production method of polyaniline electromagnetic shielding fabrics. The production method comprises introducing amino on the surface of textiles through the surface etching and activation effect of a low-temperature plasma; grafting an aniline monomer onto the surface of the textiles through the crosslinking effect of crosslinking resin; generating a polyaniline layer on the surface of the textiles through in-situ liquid phase polymerization. According to the polyaniline electromagnetic shielding fabrics, the shielding on low frequency electromagnetic waves which are below 10 MHz can reach more than 18 dB and the washing resistance is good.

Description

A kind of preparation method of polyaniline electromagnetic shielding fabric

technical field

The invention belongs to the technical field of textiles, and in particular relates to a preparation method of a polyaniline electromagnetic shielding fabric.

Background technique

With the continuous advancement of science and technology, there are more and more electronic products. While they bring convenience to people's lives, they also bring the problem of electromagnetic radiation. The refrigerators, induction cookers, microwave ovens, computers, air conditioners, electric blankets, mobile phones, etc. that we use in our daily life will produce different degrees of electromagnetic radiation. Long-term electromagnetic radiation can cause functional changes in people's nervous system, secretion and metabolic system disorders, vision loss and other diseases. Therefore, electromagnetic radiation is called the "invisible killer" of human health, and it is the fourth largest pollution source after air pollution, water pollution and noise pollution.

Electromagnetic shielding fabrics are an important way to protect the human body from electromagnetic radiation. The electromagnetic shielding fabric currently on the market is mainly prepared by adding conductive fillers during the spinning process to prepare anti-electromagnetic radiation fibers, and then blending with ordinary fibers; or by plating a metal layer on the surface of the fabric fibers. These methods are not only complex in process, but also have poor wearing properties of the fabric.

Conductive polymers have the advantages of light weight, good toughness, good stability, and easy-to-adjust electrical conductivity, and are widely used in the fields of microwave absorption and electromagnetic wave interference shielding. Due to problems such as weak combination of polyaniline and matrix fibers, uneven surface dispersion, etc., the electromagnetic shielding fabric obtained often has poor stability and the electromagnetic shielding effect is not resistant to washing.

Contents of the invention

In order to overcome the deficiencies of the prior art, the present invention provides a method for preparing polyaniline electromagnetic shielding fabrics. In the method, firstly, low-temperature plasma is used to introduce amino groups on the surface of textiles, and then cross-linking resin is used as a cross-linking agent to synthesize aniline monomer Grafting to the surface of the textile, and then adopting the method of liquid phase in-situ polymerization to generate a polyaniline layer on the surface of the textile in situ. The obtained fabric not only has good electromagnetic shielding effect, but also has good stability and washability.

A kind of preparation method of polyaniline electromagnetic shielding fabric provided by the invention comprises the following steps:

(1) Place the textiles on the shelf in the chamber of the DT-01 low-temperature plasma processor produced by Suzhou Opus Plasma Technology Co., Ltd., heat ethylenediamine or ammonia water in a water bath at 80-100°C to generate steam; turn on the vacuum pump, When the vacuum degree in the reaction chamber is 5Pa, pass ethylenediamine or ammonia water vapor into the plasma chamber, and at the same time pass in the gas, adjust the gas flow rate until the vacuum degree in the reaction chamber is 20-50Pa; stabilize for 3-5min and then glow discharge , the discharge power is 30-100W, and the discharge time is 3-10min. After the discharge is completed, take out the fabric and immediately enter the next step;

Wherein, the textiles are cellulose fiber textiles, specifically cotton, hemp, viscose fabrics, or their interwoven fabrics, or their interwoven fabrics with other fibers; the gas is air or nitrogen.

(2) Prepare aniline solution according to the following formula:

Pad the textiles treated with low-temperature plasma with the above-mentioned aniline solution, two dips and two pads, the excess rate is 70-90%, dry at 80-100°C for 3-5min, bake at 150-160°C for 2-5min, wash with water 3-5 times, dry for later use.

Among them, the crosslinking resin is dimethylol ethylene urea, dimethylol dihydroxy ethylene urea, dimethylol melamine, etherified modified dimethylol ethylene urea, etherified modified dimethylol urea One of dihydroxyethylene urea and etherified modified dimethylol melamine. The catalyst is one of anhydrous magnesium chloride and anhydrous aluminum chloride.

(3) Immerse the textiles obtained in step (2) in the aniline monomer solution, take them out after immersion for 1-2h, roll them after cooling, and the excess rate is 80-100%; then the textiles are immersed in the reaction of doping acid and oxidant In the solution, continuously and evenly stirred, oxidatively polymerized at 10-25°C for 60-120 minutes, taken out, washed with water, and dried to obtain polyaniline electromagnetic shielding fabric.

Among them, the aniline monomer is a mixture of aniline and aniline derivatives, wherein the mass content of aniline monomer is not less than 95%, and the aniline derivatives are m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, p-phenylenediamine, p-phenylenediamine, One or more of aminobenzenesulfonic acid, m-aminobenzenesulfonic acid, o-aminophenol, m-aminophenol.

Above-mentioned doping acid is a kind of in hydrochloric acid, sulfuric acid, p-toluenesulfonic acid, and acid concentration is 1-2mol/L; Oxidizing agent is a kind of in ammonium persulfate, sodium persulfate, potassium persulfate, and oxidizing agent concentration is 0.1- 0.25mol/L.

The invention first adopts low-temperature plasma to etch and activate the textile, introduces amino groups on the surface, and then grafts aniline monomers to the surface of the textile by using the cross-linking effect of the cross-linking resin. During the subsequent in-situ polymerization of aniline monomers on textiles, the aniline monomers grafted onto the surface of textiles will participate in polymerization, thereby greatly improving the binding fastness of polyaniline to textiles.

The beneficial effect of the present invention is that: the surface etching and activation of the low-temperature plasma, and the crosslinking of the crosslinking resin greatly improve the bonding fastness of the conductive polymer and the textile, and the obtained electromagnetic shielding fabric not only has a good shielding effect, but also has a wash.

Detailed ways

The present invention will be described in further detail below in conjunction with specific embodiments. It should be understood that these examples are only for illustration of the present invention, but not to limit the scope of the present invention in any way.

Example 1

(1) Put the pure cotton fabric on the shelf in the chamber of the DT-01 low-temperature plasma processing instrument produced by Suzhou Opus Plasma Technology Co., Ltd., and heat the ammonia water in an 80°C water bath to generate steam; turn on the vacuum pump, and when the reaction chamber When the vacuum degree is 5Pa, the ammonia water vapor is passed into the plasma chamber, and the air is passed in at the same time, and the gas flow rate is adjusted until the vacuum degree in the reaction chamber is 20Pa; after 3 minutes of stabilization, the glow discharge is performed, the discharge power is 30W, and the discharge time is 10min. , immediately enter the next step after taking out the fabric;

(2) Prepare aniline solution according to the following formula:

The pure cotton fabric treated with low-temperature plasma was padded with the above-mentioned aniline solution, two dips and two pads, the puffing rate was 70%, dried at 80°C for 5 minutes, then baked at 150°C for 5 minutes, washed 3 times with water, and dried for later use.

(3) Immerse the pure cotton fabric obtained in step (2) in the solution of aniline monomer (the mass fraction of aniline monomer is 98%, and the mass fraction of m-phenylenediamine is 2%), take it out after soaking for 1h, and roll it after cooling Then the textile is immersed in the reaction solution of 1mol/L hydrochloric acid and 0.1mol/L sodium persulfate, continuously and uniformly stirred, oxidatively polymerized at 10°C for 120min, taken out, washed with water, and dried to obtain the polymer Aniline electromagnetic shielding fabric.

Comparative example 1

(1) Put the pure cotton fabric on the shelf in the chamber of the DT-01 low-temperature plasma processing instrument produced by Suzhou Opus Plasma Technology Co., Ltd., and heat the ammonia water in an 80°C water bath to generate steam; turn on the vacuum pump, and when the reaction chamber When the vacuum degree is 5Pa, the ammonia water vapor is passed into the plasma chamber, and the air is passed in at the same time, and the gas flow rate is adjusted until the vacuum degree in the reaction chamber is 20Pa; after 3 minutes of stabilization, the glow discharge is performed, the discharge power is 30W, and the discharge time is 10min. , go to the next step immediately after taking out the fabric;

(2) Immerse the pure cotton fabric obtained in step (1) in the solution of aniline monomer (the mass fraction of aniline monomer is 98%, and the mass fraction of m-phenylenediamine is 2%), take it out after soaking for 1h, and roll it after cooling Then the textile is immersed in the reaction solution of 1mol/L hydrochloric acid and 0.1mol/L sodium persulfate, continuously and uniformly stirred, oxidatively polymerized at 10°C for 120min, taken out, washed with water, and dried to obtain the polymer Aniline electromagnetic shielding fabric.

Example 2

(1) Put the pure hemp textiles on the shelf in the chamber of DT-01 low-temperature plasma processing apparatus produced by Suzhou Opus Plasma Technology Co., Ltd., heat ethylenediamine in a 100°C water bath to generate steam; turn on the vacuum pump, and when the reaction When the vacuum degree in the chamber is 5Pa, pass ethylenediamine vapor into the plasma chamber and nitrogen gas at the same time, adjust the gas flow until the vacuum degree in the reaction chamber is 50Pa; after 5 minutes of stabilization, glow discharge, discharge power 100W, discharge time 3min , after the discharge is over, take out the fabric and immediately enter the next step;

(2) Prepare aniline solution according to the following formula:

The low-temperature plasma-treated textiles were padded with the above-mentioned aniline solution, two dips and two pads, the excess rate was 90%, dried at 100°C for 3 minutes, then baked at 160°C for 2 minutes, washed 5 times with water, and dried for later use.

(3) Immerse the textiles obtained in step (2) in the solution of aniline monomer (the mass fraction of aniline monomer is 96%, and the mass fraction of o-phenylenediamine monomer is 4%) solution, take it out after immersion for 2h, and roll it after cooling Then, the textile is immersed in the reaction solution of 2mol/L sulfuric acid and 0.25mol/L ammonium persulfate, continuously and uniformly stirred, oxidatively polymerized at 25°C for 60min, taken out, washed with water, and dried to obtain the polymer Aniline electromagnetic shielding fabric.

Comparative example 2

(1) Prepare aniline solution according to the following formula:

Pad the pure hemp textiles with the above-mentioned aniline solution, two dips and two pads, the excess rate is 90%, dry at 100°C for 3 minutes, then bake at 160°C for 2 minutes, wash with water 5 times, and dry for later use.

(2) Immerse the textiles obtained in step (1) in the solution of aniline monomer (the mass fraction of aniline monomer is 96%, and the mass fraction of o-phenylenediamine monomer is 4%) solution, take it out after immersion for 2h, and roll it after cooling Then, the textile is immersed in the reaction solution of 2mol/L sulfuric acid and 0.25mol/L ammonium persulfate, continuously and uniformly stirred, oxidatively polymerized at 25°C for 60min, taken out, washed with water, and dried to obtain the polymer Aniline electromagnetic shielding fabric.

Example 3

(1) Place the viscose fabric on the shelf in the chamber of the DT-01 low-temperature plasma processor produced by Suzhou Opus Plasma Technology Co., Ltd., and heat the ammonia water in a 90°C water bath to generate steam; turn on the vacuum pump, and when the reaction chamber When the vacuum degree is 5Pa, the ammonia water vapor is passed into the plasma chamber, and the air is passed in at the same time, and the gas flow rate is adjusted until the vacuum degree in the reaction chamber is 30Pa; after 4 minutes of stabilization, the glow discharge is performed, the discharge power is 50W, and the discharge time is 5min. , go to the next step immediately after taking out the fabric;

(2) Prepare aniline solution according to the following formula:

The low-temperature plasma-treated textiles were padded with the above-mentioned aniline solution, two dips and two pads, with a pass rate of 80%, dried at 90°C for 4 minutes, then baked at 155°C for 4 minutes, washed 4 times, and dried for later use.

(3) Immerse the viscose fabric obtained in step (2) in the solution of aniline monomer (the mass fraction of aniline monomer is 98%, and the mass fraction of m-aminophenol is 2%), take it out after immersion for 1.5h, and roll it after cooling Then, the textile is immersed in the reaction solution of 1.5mol/L p-toluenesulfonic acid and 0.15mol/L potassium persulfate, continuously and evenly stirred, oxidatively polymerized at 15°C for 90min, taken out, washed with water, and dried , that is, polyaniline electromagnetic shielding fabric.

Example 4

(1) Put cotton/hemp blended textiles (80% cotton fiber quality and 20% hemp fiber quality) on the shelf in the cavity of DT-01 low-temperature plasma processing instrument produced by Suzhou Opus Plasma Technology Co., Ltd. , heat ethylenediamine in a water bath at 95°C to generate steam; turn on the vacuum pump, and when the vacuum in the reaction chamber is 5Pa, pass ethylenediamine vapor into the plasma chamber and nitrogen gas at the same time to adjust the gas flow to the vacuum in the reaction chamber 40Pa; after 3.5 minutes of stabilization, glow discharge, the discharge power is 60W, and the discharge time is 7 minutes. After the discharge, take out the fabric and immediately enter the next step;

(2) Prepare aniline solution according to the following formula:

The low-temperature plasma-treated textiles were padded with the above-mentioned aniline solution, two dips and two pads, the excess rate was 85%, dried at 95°C for 3.5 minutes, then baked at 150°C for 4.5 minutes, washed 5 times with water, and dried for later use.

(3) Immerse the textiles obtained in step (2) in the monomer solution of anilines (the mass fraction of aniline monomer is 95%, and the mass fraction of p-phenylenediamine is 5%), take it out after immersion for 1.2h, and roll it after cooling , the excess rate is 85%; then immerse the textile in the reaction solution of 1.2mol/L hydrochloric acid and 0.17mol/L ammonium persulfate, continue to stir evenly, oxidatively polymerize at 20°C for 75min, take it out, wash it with water, and dry it to obtain polyaniline Electromagnetic shielding fabric.

Example 5

The shielding effectiveness is tested with the DR-913 fabric anti-electromagnetic radiation performance tester, and the reference standards GB/T25471 "Measurement Method for Shielding Effectiveness of Electromagnetic Shielding Coating" and SJ204524 "Test Method for Shielding Effectiveness of Materials".

The washability test is completed in a washing fastness tester. The washing procedure is as follows (this washing procedure is equivalent to 10 washes): 40°C, 0.2% detergent concentration, 150mL solution, 10 steel balls, wash for 45min. After washing, take out the sample, wash it twice in cold water, and dry it at 80°C for 10 minutes to measure the electromagnetic shielding performance of the fabric.

Measure embodiment 1～4, comparative example 1～2 gained electromagnetic shielding fabric shielding effectiveness and washing resistance by the above method, the results are shown in Table 1:

Table 1 Fabric electromagnetic shielding performance

As can be seen from Table 1, the shielding effectiveness of the electromagnetic shielding fabric obtained in Examples 1-4 to low-frequency electromagnetic waves below 10MHz reaches more than 18dB, which can shield more than 97% of electromagnetic waves; The effectiveness has declined; the shielding performance of the fabric is very washable, and after washing, the electromagnetic shielding effectiveness is slightly reduced. In comparative example 1, since no cross-linked resin was used, the conductive polyaniline layer and the textile were combined only by physical adsorption and intermolecular force, and the combination of the two was weak. After washing with water, the electromagnetic shielding effect was greatly reduced. From the experimental data of Example 2 and Comparative Example 2, it can be seen that the surface etching and activation of low-temperature plasma are beneficial to improve the bonding fastness between the polyaniline layer and the textile.

Claims (9)

1. a preparation method for polyaniline Electromagnetically shielding fabrics, is characterized in that: described preparation method is,

First adopt low temperature plasma to introduce amino at textile surface, be then crosslinking agent with crosslinked resin, aniline monomer be grafted to textile surface, then adopt the mode of liquid phase in-situ polymerization, at textile surface in-situ preparation polyaniline.

2. the preparation method of a kind of polyaniline Electromagnetically shielding fabrics as claimed in claim 1, is characterized in that: the concrete steps of described method are,

(1) textiles is placed on the shelf in the DT-01 Low Temperature Plasma Treating instrument cavity of Suzhou Ao Pusi plasma Science and Technology Ltd. production, with 80-100 DEG C of heating water bath ethylenediamine or ammonia water generates steam; Open vavuum pump, when vacuum in reaction cavity is 5Pa, passes in plasma chamber, pass into gas simultaneously by ethylenediamine or ammonia vapor, in adjusting gas flow to reaction cavity, vacuum is 20-50Pa; Stablize glow discharge after 3-5min, discharge power 30-100W, discharge time, 3-10min, after electric discharge terminates, entered next step operation immediately after being taken out by fabric;

(2) by following formulated aniline solution:

By the above-mentioned aniline solution of textile product padding crossed through Low Temperature Plasma Treating, two leachings two are rolled, and after pick-up 70-90%, 80-100 DEG C of drying 3-5min, 150-160 DEG C bakes 2-5min, washes 3-5 time, drying for standby;

(3) step (2) gained textiles is immersed in phenyl amines monomer solution, take out after dipping 1-2h, roll roll compacting after cooling, pick-up 80-100%; Then immersed by textiles in the reactant liquor of dopant acid and oxidant, continuous uniform stirs, oxidation polymerization 60-120min at 10-25 DEG C, takes out, and washing is dried, obtained polyaniline Electromagnetically shielding fabrics.

3. the preparation method of a kind of polyaniline Electromagnetically shielding fabrics as claimed in claim 2, it is characterized in that: the textiles described in step (1) is cellulose fiber textile, be specially cotton, fiber crops, viscose fabric, or both intertextures, or the intertexture of they and other fibers.

4. the preparation method of a kind of polyaniline Electromagnetically shielding fabrics as claimed in claim 2, is characterized in that: the gas described in step (1) is air or nitrogen.

5. the preparation method of a kind of polyaniline Electromagnetically shielding fabrics as claimed in claim 2, is characterized in that: crosslinked resin described in step (2) is the one in dihydroxymethyl ethylene-urea, dihydroxymethyl dihydroxy ethylene-urea, dihydroxymethyl melamine, etherification modified dihydroxymethyl ethylene-urea, etherification modified dihydroxymethyl dihydroxy ethylene-urea, etherification modified dihydroxymethyl melamine.

6. the preparation method of a kind of polyaniline Electromagnetically shielding fabrics as claimed in claim 2, is characterized in that: catalyst described in step (2) is the one in anhydrous magnesium chloride, anhydrous Aluminum chloride.

7. the preparation method of a kind of polyaniline Electromagnetically shielding fabrics as claimed in claim 2, it is characterized in that: phenyl amines monomer described in step (3) is the mixture of aniline and anil composition, wherein, the mass content of aniline monomer is not less than 95%, and anil is one or more in m-phenylene diamine (MPD), o-phenylenediamine, p-phenylenediamine (PPD), sulfanilic acid, metanilic acid, o-aminophenol, m-aminophenol.

8. the preparation method of a kind of polyaniline Electromagnetically shielding fabrics as claimed in claim 2, is characterized in that: dopant acid described in step (3) is the one in hydrochloric acid, sulfuric acid, p-methyl benzenesulfonic acid, and acid concentration is 1-2mol/L.

9. the preparation method of a kind of polyaniline Electromagnetically shielding fabrics as claimed in claim 2, is characterized in that: oxidant described in step (3) is the one in ammonium persulfate, sodium peroxydisulfate, potassium peroxydisulfate, and oxidant concentration is 0.1-0.25mol/L.