CN105133285A - Method for performing durable flame-retardant grafting modification on fabric through cooperation of low-temperature plasma with electron beam irradiation - Google Patents

Abstract

The invention discloses a durable flame-retardant grafting modification method for fabrics by low-temperature plasma and electron beam radiation: first, the fabric is placed in a low-temperature plasma device for low-temperature plasma pretreatment; then the fabric is treated with sodium hydroxide Treatment in the solution to remove impurities such as colloid in the fabric; take out the fabric and wash it fully, remove the residual sodium hydroxide, put it in an oven for drying, take it out and weigh it; soak the dried fabric in the grafted monomer solution, and then take out the excess liquid through rolling, wrap the fabric with plastic film, put it in a ziplock bag, and put the fabric together with the ziplock bag under high-energy electron beams for irradiation; after the irradiation, the grafted The finished fabric is cleaned with deionized water to remove the homopolymer and unreacted graft monomer on the surface of the fabric; then the cleaned fabric is put into an oven to dry for 24 hours to obtain the product. It has the advantages of long-lasting flame-retardant effect of fabric and strong washing resistance.

Description

A method for durable flame-retardant graft modification of fabrics by low-temperature plasma and electron beam radiation

technical field

The invention relates to a fabric grafting modification method, in particular to a durable flame-retardant grafting modification method for fabrics by low-temperature plasma and electron beam radiation.

Background technique

Low-temperature plasma technology is to use the plasma of inert gas or reactive gas to treat the surface of the material, and the surface macromolecules are activated and decomposed. The decomposed monomers may re-polymerize on the surface of the material, and may also generate gas to volatilize. The former can significantly roughen the material, while the latter has an etching effect on the surface of the material. Low-temperature plasma technology can be used in many fields such as sizing and desizing of fabrics, degumming of hemp fibers, calendering of fabrics, and hydrophilic treatment of synthetic fibers. Its own performance, so the application in the textile industry is of great significance.

Electron beam irradiation grafting technology is the use of high-energy electron beams accelerated by high-voltage electric fields to irradiate substances, and the high-energy electrons make the substances produce excited state molecules and trigger various chemical reactions, thereby changing or improving the properties of the substances. Through irradiation, the long linear macromolecules between the polymer materials are connected by a certain form of chemical bonds to form a network structure, which can greatly enhance the binding force between the polymers, thereby enhancing the thermal stability and resistance of the material. flammability, chemical stability, etc. At the same time, compared with irradiation methods such as gamma rays, high-energy electron beam irradiation technology has wider energy range, better beam focusing, higher energy utilization rate, no risk of radiation leakage, and no need to deal with radiation. source of waste etc. When the high-energy electron beam acts on the material, it can destroy the chemical bonds of the material, generate active ions or free radicals, and destroy or cross-link the material. The advantages of using high-energy electron beams for grafting reaction are: this method is simple and easy to operate, does not require any initiators and does not require finishing, and uses charged particles to modify materials without secondary pollution. It is an efficient and environmentally friendly , Low cost and other advantages.

Textiles are widely used in various fields such as clothing and decoration, but because the fibers are extremely flammable, it will increase unsafe factors in use. Therefore, the flame-retardant finishing of textiles has become a subject of concern. The flame retardant function of fabrics is extremely important to eliminate fire hazards, delay the spread of fire, and reduce the loss of people's lives and property. The use of flame retardant technology is one of the strategic measures to improve fire safety and reduce fire losses. And the increasingly stringent flame retardant standards and the implementation of environmental protection regulations make flame retardant materials must meet the requirements of both aspects at the same time. Therefore, at home and abroad, we attach great importance to the research on new flame-retardant finishing of fabrics, requiring fabrics not only to have good flame-retardant properties, but also to be environmentally friendly, so grafting and modifying the surface of fabrics to enhance their flame-retardant effects has become a research topic. hotspot.

Contents of the invention

The object of the present invention is to provide a durable flame-retardant graft modification method for fabrics by low-temperature plasma and electron beam radiation.

The purpose of the present invention is achieved through the following technical solutions.

A method for durable flame-retardant graft modification of fabrics by low-temperature plasma in cooperation with electron beam radiation, the steps of which are as follows:

(1) The fabric is first placed in a low-temperature plasma device for low-temperature plasma pretreatment;

(2) The fabric is then treated with sodium hydroxide solution for 30 minutes at 95-100°C to remove impurities such as colloids in the fabric;

(3) After the fabric is taken out, it is fully washed with water, and after removing the residual sodium hydroxide, put it in an oven and dry it at 80-90°C for 1-3h, take it out and weigh it;

(4) Soak the dried fabric in the grafting monomer solution for 1-3 hours, then take it out and roll out the excess liquid by rolling, wrap the fabric with plastic film, put it in a ziplock bag, put the fabric together with the ziplock bag Putting it under a high-energy electron beam for irradiation;

(5) After the irradiation finishes, the fabric after grafting is cleaned with deionized water, removes the homopolymer of fabric surface and unreacted grafting monomer; Then the fabric after cleaning is put into drying oven for 24 hours , get the product.

In step (1), the fabrics include fabrics and textiles made of hemp such as flax, ramie, jute, cotton fibers, bamboo fibers, lotus fibers and various new cellulosic fibers.

In step (1), the process conditions of the low-temperature plasma pretreatment are: the working gas used is a mixed gas of one or more gases in argon, nitrogen, oxygen and air; the working pressure is 10-150Pa, The discharge power is 10-300W, and the processing time is 1-20min.

In step (2), the concentration of the sodium hydroxide solution is 15-30g/L.

In step (4), the high-energy electron beam irradiation reaction conditions are: the irradiation dose is 0-100 kGy and the corresponding conversion value of other radiation units.

In step (4), the atmosphere and temperature conditions during the electron beam irradiation are not limited, and the atmosphere can be classified into atmospheric environment, vacuum environment or inert gas environment containing nitrogen and/or helium.

In step (4), in the grafted monomer solution, the solute is one of vinyl monomers such as acrylamide, methacrylamide, acrylic acid and methacrylic acid, and its concentration is 0.1-10mol/L; solvent for water.

The grafted monomer solvent can be used in combination with other functional finishing agents without affecting the effects of other functional finishing agents.

The advantages of the present invention are:

Compared with the existing flame-retardant finishing methods such as coating finishing and impregnation, these traditional flame-retardant methods are often not durable for flame-retardant finishing of fabrics, and the process is longer, the operation of processing equipment is complicated, and there are many uncontrollable factors. , making it difficult to control the flame retardant effect of the fabric. At the same time, these sorting methods will increase the cost of sewage treatment.

Compared with the existing technology of irradiating and grafting fabrics, the method of irradiating fabrics with ultraviolet light has a grafting reaction, and the irradiation dose is small, so the number of free radicals produced is relatively small, which will lead to grafting. The rate is low, which in turn affects the flame retardant effect of the fabric.

In the present invention, low-temperature plasma technology and high-energy electron beam radiation treatment are used for the durable flame-retardant grafting modification of fabrics for the first time, and after low-temperature plasma pretreatment, the grafting rate of fabrics is greatly improved, thereby The flame retardant performance is significantly improved.

The present invention is the first to use vinyl monomers such as acrylamide to graft high-energy electron beams of fabrics so as to improve the flame-retardant performance of fabrics. The flame retardant performance of the modified fabric is obviously improved, and the vertical burning test shows that its afterburning time and smoldering time are obviously reduced. And the monomer and the fabric are connected by covalent bonds, so the flame retardant effect of the fabric after grafting modification has a certain degree of washing resistance and the effect is long-lasting.

Low-temperature plasma is used to etch the colloid on the surface of the fabric, so that part of the colloid on the fiber is loosened and broken, and it is easy to remove. After high-temperature scouring with sodium hydroxide solution, the degumming of the fiber surface is more thorough. Impurities are also removed more cleanly, which facilitates the subsequent grafting reaction.

The low-temperature plasma pretreatment adopted in the present invention is a physical method that does not need to use water, steam, chemicals, etc., thereby reducing sewage discharge and energy consumption, and is an environmentally friendly pretreatment method.

In the present invention, high-energy electron beams are used to carry out grafting reaction on fabrics. The radiation energy of high-energy electron beams is high, and the penetrating ability is strong. The reaction can go deep into the fabric, and the fabrics are evenly grafted. Moreover, no initiator is needed in the process of high-energy electron beam treatment of fabrics, and it has the advantages of fast reaction speed, simple and easy operation, no post-finishing, etc., and no secondary pollution.

The flame-retardant fabric of the invention can be applied to textile fields such as clothing, decoration, and home textiles, and the fabric produced by the method has a durable flame-retardant effect and is comfortable to the touch.

Detailed ways

The technical characteristics of the present invention will be further elaborated below in conjunction with specific embodiments.

Embodiment one

Firstly, the linen fabric is pretreated for 120s in a low-temperature plasma device with working gas of N ₂ , working pressure of 10Pa, and discharge power of 100W, and then the fabric is pretreated with sodium hydroxide solution at 95-100°C for 30min , remove impurities, and then fully wash the fabric, remove the residual alkali and put the fabric in an oven for drying at a temperature of 80-90°C. The fabric was removed after drying and the mass of the linen was weighed. Then soak the fabric in the acrylamide monomer solution with a concentration of 2mol/l for 2.5h, and then put the fabric into a high-energy electron beam for irradiation after one-dipping and one-rolling (the speed of the padding car is 1m/min, the pressure is 0.1Mpa). Irradiation dose was 22KGy. After the reaction, the fabric was taken out and cleaned with deionized water to remove homopolymers and unreacted graft monomers on the surface of the fabric, and finally dried in an oven to constant weight. The surface grafting rate of the obtained linen fabric was 12.58%. The vertical burning test showed that the afterburning time and smoldering time were reduced to 4s and 3s respectively, and the limiting oxygen index was 31%. After washing 20 times, the after-flame time and smoldering time measured by the same method are 5s and 4s respectively, and the limiting oxygen index is 30%. It shows that the obtained durable flame-retardant linen fabric has good durable flame-retardant effect.

Embodiment two

Firstly, the linen fabric is pretreated for 150s in a low-temperature plasma device with working gas of N ₂ , working pressure of 10Pa, and discharge power of 100W, and then the fabric is pretreated with sodium hydroxide solution at 95-100°C for 30min , remove impurities, and then fully wash the fabric, remove the residual alkali and put the fabric in an oven for drying at a temperature of 80-90°C. The fabric was removed after drying and the mass of the linen was weighed. Then soak the fabric in the acrylamide monomer solution with a concentration of 2mol/l for 2.5h, and then put the fabric into a high-energy electron beam for irradiation after one-dipping and one-rolling (the speed of the padding car is 1m/min, the pressure is 0.1Mpa). Irradiation dose was 43KGy. After the reaction, the fabric was taken out and cleaned with deionized water to remove homopolymers and unreacted graft monomers on the surface of the fabric, and finally dried in an oven to constant weight. The surface grafting rate of the linen fabric is 24.20%. The vertical burning test shows that the afterflame time and smoldering time are reduced to 3s and 2s respectively, and the limiting oxygen index is 34%. After washing 20 times, the after-flame time and smoldering time measured by the same method were 4s and 3s respectively, and the limiting oxygen index was 31%. It shows that the obtained durable flame-retardant linen fabric has good durable flame-retardant effect.

Embodiment three

Firstly, the linen fabric is pretreated for 180s in a low-temperature plasma device with working gas of N ₂ , working pressure of 10Pa, and discharge power of 100W, and then the fabric is pretreated with sodium hydroxide solution at 95-100°C for 30min , remove impurities, and then fully wash the fabric, remove the residual alkali and put the fabric in an oven for drying at a temperature of 80-90°C. The fabric was removed and the mass of the linen was weighed. Then soak the fabric in the acrylamide monomer solution with a concentration of 2mol/l for 2.5h, and then put the fabric into a high-energy electron beam for irradiation after one-dipping and one-rolling (the speed of the padding car is 1m/min, the pressure is 0.1Mpa). Irradiation dose was 65KGy. After the reaction, the fabric was taken out and cleaned with deionized water to remove homopolymers and unreacted graft monomers on the surface of the fabric, and finally dried in an oven to constant weight. The surface grafting rate of the linen fabric is 36.78%. The vertical burning test shows that the afterflame time and smoldering time are reduced to 2s and 1s respectively, and the limiting oxygen index is 37%. After washing 20 times, the after-flame time and smoldering time measured by the same method are 3s and 3s respectively, and the limiting oxygen index is 34%. It shows that the obtained durable flame-retardant linen fabric has good durable flame-retardant effect.

Embodiment four

Firstly, the linen fabric is pretreated for 180s in a low-temperature plasma device with working gas of N ₂ , working pressure of 15Pa, and discharge power of 100W, and then the fabric is pretreated with sodium hydroxide solution at 95-100°C for 30min , remove impurities, and then fully wash the fabric, remove the residual alkali and put the fabric in an oven for drying at a temperature of 80-90°C. The fabric was removed and the mass of the linen was weighed. Then soak the fabric in the acrylamide monomer solution with a concentration of 2mol/l for 2.5h, and then put the fabric into a high-energy electron beam for irradiation after one-dipping and one-rolling (the speed of the padding car is 1m/min, the pressure is 0.1Mpa). Irradiation dose was 65KGy. After the reaction, the fabric was taken out and cleaned with deionized water to remove homopolymers and unreacted graft monomers on the surface of the fabric, and finally dried in an oven to constant weight. The surface grafting rate of the linen fabric is 37.43%. The vertical burning test shows that the afterflame time and smoldering time are reduced to 2s and 1s respectively, and the limiting oxygen index is 38%. After washing 20 times, the after-flame time and smoldering time measured by the same method are 2s and 3s respectively, and the limiting oxygen index is 35%. It shows that the obtained durable flame-retardant linen fabric has good durable flame-retardant effect.

Embodiment five

First place the linen fabric in a low-temperature plasma device with working gas N ₂ , working pressure 20Pa, and discharge power 100W for 180s, and then pretreat the fabric with sodium hydroxide solution at 95-100°C for 30 minutes , remove impurities, and then fully wash the fabric, remove the residual alkali and put the fabric in an oven for drying at a temperature of 80-90°C. The fabric was removed and the mass of the linen was weighed. Then soak the fabric in the acrylamide monomer solution with a concentration of 2mol/l for 2.5h, and then put the fabric into a high-energy electron beam for irradiation after one-dipping and one-rolling (the speed of the padding car is 1m/min, the pressure is 0.1Mpa). Irradiation dose was 65KGy. After the reaction, the fabric was taken out and cleaned with deionized water to remove homopolymers and unreacted graft monomers on the surface of the fabric, and finally dried in an oven to constant weight. The surface grafting rate of the linen fabric is 38.21%. The vertical burning test shows that the afterflame time and smoldering time are reduced to 2s and 1s respectively, and the limiting oxygen index is 38.5%. After washing 20 times, the after-flame time and smoldering time measured by the same method are 3s and 2s respectively, and the limiting oxygen index is 36%. It shows that the obtained durable flame-retardant linen fabric has good durable flame-retardant effect.

Embodiment six

Firstly, the linen fabric is pretreated for 180s in a low-temperature plasma device with working gas of N ₂ , working pressure of 10Pa, and discharge power of 150W, and then the fabric is pretreated with sodium hydroxide solution at 95-100°C for 30min , remove impurities, and then fully wash the fabric, remove the residual alkali and put the fabric in an oven for drying at a temperature of 80-90°C. The fabric was removed and the mass of the linen was weighed. Then soak the fabric in the acrylamide monomer solution with a concentration of 2mol/l for 2.5h, and then put the fabric into a high-energy electron beam for irradiation after one-dipping and one-rolling (the speed of the padding car is 1m/min, the pressure is 0.1Mpa). Irradiation dose was 65KGy. After the reaction, the fabric was taken out and cleaned with deionized water to remove homopolymers and unreacted graft monomers on the surface of the fabric, and finally dried in an oven to constant weight. The surface grafting rate of the linen fabric is 38.89%. The vertical burning test shows that the afterflame time and smoldering time are reduced to 1s and 1s respectively, and the limiting oxygen index is 38.7%. After washing 20 times, the after-flame time and smoldering time measured by the same method are 2s and 2s respectively, and the limiting oxygen index is 36.5%. It shows that the obtained durable flame-retardant linen fabric has good durable flame-retardant effect.

Comparative example one

In order to compare with the present invention, the linen fabric is not processed through the low-temperature plasma pretreatment process, and other conditions are treated under the same conditions as in Example 1. The surface grafting rate of the obtained linen fabric was 9.64%. The vertical burning test showed that the afterburning time and smoldering time were reduced to 8s and 7s respectively, and the limiting oxygen index was 29%. After washing 20 times, the after-flame time and smoldering time measured by the same method are 6s and 5s respectively, and the limiting oxygen index is 27%.

Through the comparison of Example 1 and Comparative Example 1, it can be seen that the grafting rate and flame retardant effect of the linen fabric after the low-temperature plasma pretreatment process have been significantly improved, and the durability of its flame retardant effect is also better. . This shows that the present invention has leading property.

The examples listed in the present invention are only for the purpose of explanation, each reaction substance and reaction condition can realize the present invention at the upper and lower limits of each process parameter, and no longer list examples here.

Other improvements and changes directly derived or conceived by those skilled in the art without departing from the spirit and concept of the present invention shall be considered within the protection scope of the present invention.

Claims (7)

1. low-temperature plasma synergistic electron beam irradiation is to a durable flame-retardant graft-modification method for fabric, it is characterized in that: the steps include:

(1) first fabric is placed in low-temperature plasma device and carries out low temperature plasma preliminary treatment;

(2) then fabric sodium hydroxide solution is processed 30min under the condition of 95-100 DEG C, the impurity such as the colloid in removing fabric;

(3) wash fully after being taken out by fabric, putting into baking oven after removing residual hydrogen sodium oxide molybdena under the condition of 80-90 DEG C dries 1-3h, and taking-up is weighed;

(4) fabric of oven dry is immersed in 1-3 hour in grafted monomers solution, takes out subsequently and shut out surplus liquid through padding machine, fabric plastic sheeting is wrapped, puts into valve bag, under fabric is put into high-power electron beam together with valve bag, carry out irradiation;

(5) after irradiation terminates, by the fabric washed with de-ionized water after grafting, the homopolymers of removing fabric face and unreacted grafted monomers; Then the fabric after cleaning is put into baking oven to dry 24 hours, obtain product.

2. a kind of low-temperature plasma synergistic electron beam irradiation according to claim 1 is to the durable flame-retardant graft-modification method of fabric, it is characterized in that: in step (1), described fabric comprises crudefiber crop, cotton fiber and the bamboo fibres such as flax, ramie, jute, fabric made by the various novel cellulosic fibre of lotus fiber and textiles.

3. a kind of low-temperature plasma synergistic electron beam irradiation according to claim 1 is to the durable flame-retardant graft-modification method of fabric, it is characterized in that: in step (1), the pretreated process conditions of described low temperature plasma are: the working gas of employing is the mist of one or more gases in argon gas, nitrogen, oxygen and air; Operating pressure is 10-150Pa, and discharge power is 10-300W, and the processing time is 1-20min.

4. a kind of low-temperature plasma synergistic electron beam irradiation according to claim 1 is to the durable flame-retardant graft-modification method of fabric, it is characterized in that: in step (2), and described concentration of sodium hydroxide solution is 15-30g/L.

5. a kind of low-temperature plasma synergistic electron beam irradiation according to claim 1 is to the durable flame-retardant graft-modification method of fabric, it is characterized in that: in step (4), described high-energy electron beam irradiation reaction condition is: irradiation dose is 0-100kGy and other radiation unit's transforming numericals corresponding.

6. a kind of low-temperature plasma synergistic electron beam irradiation according to claim 1 is to the durable flame-retardant graft-modification method of fabric, it is characterized in that: in step (4), atmosphere during described electron beam irradiation, temperature conditions all do not limit, and atmosphere can be divided into atmospheric environment, vacuum environment or contain the inert gas environment of nitrogen and/or helium.

7. a kind of low-temperature plasma synergistic electron beam irradiation according to claim 1 is to the durable flame-retardant graft-modification method of fabric, it is characterized in that: in step (4), in described grafted monomers solution, solute is the one in acrylamide, Methacrylamide, acrylic acid and methacrylate vinyl base monomer, and its concentration is 0.1-10mol/L; Solvent is water.