CN104911907A - Low-pressure plasma sorting method endowing cotton fabric with fluoride-free water repellent function - Google Patents

Abstract

The invention relates to a plasma preparation method of a fluoride-free water-repellent cotton fabric, which comprises the following steps: (1) generating plasma glow by using a radio frequency plasma generator with frequency of 13.56MHZ, regulating the power of a plasma to change between 60W and 140W and the time to be within the range of 60s-300s; (2) taking the cotton fabric as a matrix, taking tetramethyl tetravinyl cyclotetrasiloxane as a single precipitate, and taking helium as an atmosphere; (3) carrying out electro discharge treatment on the glow of the cotton fabric under the condition of pressure of 20Pa, thus obtaining the cotton fabric with the fluoride-free water repellent function. According to the invention, the sorting method is simple, the water repellence of the fabric is excellent, and the fabric has excellent washability.

Description

A low-pressure plasma finishing method for imparting fluorine-free water repellency to cotton fabrics

technical field

The invention relates to a fluorine-free and water-repellent finishing of cotton fabrics, which uses He as the atmosphere and tetramethyltetravinylcyclotetrasiloxane as a monomer, and adopts clean and environment-friendly low-pressure plasma treatment technology, which belongs to functional textile finishing technology field.

Background technique

Cotton fabric is the largest and most widely used variety of textile fibers in the world. Its textile products are developing in the direction of functionalization and intelligence, and have received extensive attention and research from the textile industry.

The purpose of water-repellent finishing is to make the fabric not easily wetted by water, and to produce a certain anti-fouling effect without affecting its wearing comfort, increase the added value of the product, reduce the number of washings, and prolong its service life. According to the analysis of wetting theory, the highest surface energy of water is 72.6mJ/m ² , and the surface energy of water-repellent materials must be smaller than this value. At present, the water-repellent finishing of fabrics generally uses a padding process to distribute a finishing agent with a special molecular structure on the surface of the fabric or in the gaps between the yarns. Firmly attached to the fiber or chemically combined with the fiber, thereby reducing the surface tension of the fabric.

According to the chemical structure of the water repellent itself, there are many types of water repellents that have been studied or used, mainly metal soaps (aluminum soap and zirconium soap), waxes and waxy substances, metal complexes, pyridine derivatives, Methylol compounds and fluorine-containing compounds, etc. However, due to poor durability, or damage to the fiber itself, affecting the feel and style of the fabric, as well as various reasons such as odor and color, the commonly used water repellents are mainly fluorine-containing compounds. However, there is usually a major problem in the chemical finishing of fabrics with water-repellent agents, which will pollute the environment during the finishing process.

It can be seen that the above water repellents have certain limitations in the application of traditional dipping and padding processes.

Low-pressure plasma technology is a fast, environmentally friendly and energy-saving dry production technology. It can modify the surface of textiles without affecting the mechanical properties and excellent quality of the fiber itself. The modification depth generally only involves 30% of the skin structure. ~50nm. This technology is a novel method that can replace the wet chemical treatment and modification of the surface of polymer and textile materials, and can induce the physical and chemical modification of the surface to occur instantaneously, such as etching, grafting, copolymerization and crosslinking.

But at present there is no good process simple, good water repellent effect, low-pressure plasma water repellent treatment technology for cotton fabrics with less pollution.

Contents of the invention

The invention adopts a new environment-friendly low-pressure plasma modification technology, combines monomers under low pressure to arrange cotton fabrics, so that monomers undergo graft polymerization on the surface of the fabrics, so as to achieve simple operation process, environmental protection and high efficiency, and finished fabrics after finishing. The purpose of good washing resistance of cotton fabrics.

In order to achieve the above object, the present invention adopts the following technical solutions:

A low-pressure plasma finishing method for imparting fluorine-free water repellency to cotton fabrics, comprising the following steps:

(1) Generate plasma glow with a frequency of 13.56MHZ radio frequency plasma generator, and adjust the plasma processing power and time.

(2) Cotton fabric as the substrate, tetramethyltetravinylcyclotetrasiloxane as the monomer deposition, and helium as the atmosphere.

(3) Under the condition of constant pressure, the cotton fabric was treated with glow discharge to obtain the cotton fabric with fluorine-free water-repellent function.

Further, in step (1), the plasma processing power is 60W-140W, and the time is 60s-300s.

Further, the low-pressure plasma finishing device includes a vacuum chamber, a radio frequency power generator, a pressure indicator and an automatic timing alarm.

Further, the cotton fabric is treated with glow discharge at a pressure of 20Pa.

Further, when the pressure in the vacuum chamber is less than 10Pa, helium gas is introduced, and the release button is turned on when the pressure is kept at a constant value of 20Pa after 2 to 3 cycles of inflation and deflation.

Further, the purity of the tetramethyltetravinyl cyclotetrasiloxane is 99.00%, and the purity of helium is 99.99%.

Specifically, the low-pressure plasma finishing technology of the present invention to impart fluorine-free water repellency to fabrics, the specific steps of the method are as follows:

(1) Prepare the monomer solution, soak the above cotton fabric in the solution at room temperature for 2-5 minutes, and then pass the padding machine to make the cotton fabric carry liquid rate of 80~120%;

(2) Place the cotton fabric with the monomer attached in the low-voltage radio frequency plasma reaction chamber; turn on the power switch, vacuumize, and control the pressure in the reaction chamber to be 10Pa lower than that to feed He, and reflow 2 to 3 times. Adjust the gas valve to control the pressure in the reaction chamber at 20Pa, turn on the plasma radio frequency power button, and turn on the instant button after the plasma is discharged, the processing time is 60s~300s, and the power is 60W~140W, so that the monomer is polymerized and deposited on the cotton fabric to meet the specified requirements. After a period of time, turn off the power and take out the sample.

Beneficial effect

(1) The treatment process of the present invention belongs to the dry finishing technology, which can save water resources, and there is no water pollution;

(2) The finishing method described in the present invention is simple and safe, does not need to add other additives, does not need to perform other physical or chemical reactions, and the remaining solution can be reused, which is not only clean and environmentally friendly, but also greatly reduces the process and saves costs ;

(3) The present invention can endow the fabric with excellent durability and water repellency, and the water contact angle test is greater than 130 ^° ; according to the AATCC washing resistance test standard, the contact angle still reaches more than 120 ^° after washing 30 times; at the same time, the treatment improves the cotton fabric. Softness, and has no effect on the apparent color of colored cotton fabrics.

Description of drawings

Figure 1 is the same 2000 times scanning electron microscope photo of cotton fabric before and after treatment.

Figure 2 is a photo of water droplets after 60s on the surface of the water-repellent finishing fabric.

Detailed ways

The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In the following examples, the purity of the tetramethyltetravinylcyclotetrasiloxane is 99.00%, and the purity of helium is 99.99%.

Example 1:

(1) Under normal temperature conditions, prepare tetramethyltetravinylcyclotetrasiloxane monomer solution in a glass cup, soak the above cotton fabric in the solution for 2 minutes, and then squeeze the liquid through a small paddle to control the cotton fabric The liquid carrying rate is about 80%.

(2) Use a radio frequency plasma generator with a frequency of 13.56MHZ to generate plasma glow, put the cotton fabric into a low-pressure plasma treatment chamber, turn on the power switch, evacuate to 10Pa, then feed 99% high-purity He, and cycle 2 times, maintain the pressure of the reaction chamber at 20Pa, turn on the radio frequency power button, and treat the cotton fabric with glow discharge. The discharge time is 120s, the power is 40W, and the power supply is turned off after the specified time is reached.

(3) Close the vent valve, deflate, and take out the fabric.

Example 2:

(1) Under normal temperature conditions, prepare tetramethyltetravinylcyclotetrasiloxane monomer solution in a glass cup, soak the above cotton fabric in the solution for 5 minutes, and then squeeze the liquid through a small paddle to control the cotton fabric The liquid-carrying rate is about 100%.

(2) Put the cotton fabric into the low-pressure plasma treatment chamber, turn on the power switch, evacuate to 10Pa, then feed 99% high-purity He, cycle twice, maintain the pressure of the reaction chamber at 20Pa, turn on the radio frequency power button, and discharge The time is 60s, the power is 80W, and the power is turned off after the specified time is reached.

(3) Close the vent valve, deflate, and take out the fabric.

Example 3:

(1) Under normal temperature conditions, prepare tetramethyltetravinylcyclotetrasiloxane monomer solution in a glass cup, soak the above cotton fabric in the solution for 4 minutes, and then squeeze the liquid through a small paddle to control the cotton fabric The liquid carrying rate is about 120%.

(2) Put the cotton fabric into the low-pressure plasma treatment chamber, turn on the power switch, evacuate to 10Pa, then feed 99% high-purity He, cycle twice, maintain the pressure of the reaction chamber at 20Pa, turn on the radio frequency power button, and discharge The time is 180s, the power is 80W, and the power is turned off after the specified time is reached.

(3) Close the vent valve, deflate, and take out the fabric.

Example 4:

(1) Under normal temperature conditions, prepare tetramethyltetravinylcyclotetrasiloxane monomer solution in a glass cup, soak the above cotton fabric in the solution for 3 minutes, and then squeeze the liquid through a small paddle to control the cotton fabric The liquid carrying rate is about 120%.

(2) Put the cotton fabric into the low-pressure plasma treatment chamber, turn on the power switch, evacuate to 10Pa, then feed 99% high-purity He, cycle twice, maintain the pressure of the reaction chamber at 20Pa, turn on the radio frequency power button, and discharge The time is 120s, the power is 100W, and the power is turned off after the specified time is reached.

(3) Close the vent valve, deflate, and take out the fabric.

Example 5:

(1) Under normal temperature conditions, prepare tetramethyltetravinylcyclotetrasiloxane monomer solution in a glass cup, soak the above cotton fabric in the solution for 8 minutes, and then squeeze the liquid through a small paddle to control the cotton fabric The liquid carrying rate is about 120%.

(2) Put the cotton fabric into the low-pressure plasma treatment chamber, turn on the power switch, evacuate to 10Pa, then pass through 99% high-purity He, cycle twice, maintain the pressure of the reaction chamber at 20Pa, turn on the radio frequency power button, and discharge The time is 120s, the power is 80W, and the power supply is turned off after the specified time is reached.

(3) Close the vent valve, deflate, and take out the fabric.

The performance test of the fabric after finishing of the present invention is compared with the original form, and the results are as follows:

(1) Evaluation of water-repellent effect of cotton fabric after treatment

Implementation Effect

The cotton fabrics treated in the above examples 1-5 and the comparison sample cotton fabrics were balanced for 24 hours under the same conditions, and the water contact angle was tested by using a droplet shape analyzer (KRUSS company, DSA 10MK2 type in Germany). After 60s, take the reading, measure 5 times at different positions of the same sample, and take the average value; refer to the AATCC-22-1997 washability test standard to test the washability of the fabric, and the results are shown in Table 1 below. According to the analysis of the results, after the implementation of the method of the present invention, the cotton fabric is endowed with excellent hydrophobic properties, and the fabric still has water repellency after being washed with water for 30 times.

Table 1 Water repellency and washing durability test of cotton fabric

sample Contact angle before washing ( ^o ) Contact angle after washing 10 times ( ^o ) Contact angle after washing 20 times ( ^o ) Contact angle after washing for 30 times ( ^o ) Example 1 132 130 125 124 Example 2 136 133 128 128 Example 3 146 143 138 136 Example 4 147 145 140 138 Example 5 150 147 141 140

(2) Scanning electron microscope observation of the surface morphology of cotton fabric after treatment

A JSM-5610LV scanning electron microscope was used to observe the surface morphology of the cotton fabric before and after finishing Example 1. Wherein Fig. 1 is the scanning electron microscope photo of the same magnification of 2000 times before and after the cotton fabric is processed, as shown in Fig. 1, after the method of the present invention is processed, the cotton fiber surface is coated with one deck even and flat film, and experiment proves to be polysiloxane Alkane polymer film. Figure 2 is a photo of water droplets on the surface of the water-repellent finished fabric for 60s. As shown in Figure 2, the existence of this layer of film makes the fabric have excellent hydrophobic effect.

Claims (7)

1. providing cotton fabric free-floride refuses a low pressure plasma method for sorting for water, it is characterized in that, comprises the following steps:

(1) be that 13.56MHZ RF plasma generator produces plasma glow with frequency, and regulate Cement Composite Treated by Plasma power and time;

(2) COTTON FABRIC is matrix, is monomer deposition with t etram-ethyltetravinylcyclotetrasiloxane, and is atmosphere with helium;

(3) under the condition of invariablenes pressure of liquid to COTTON FABRIC glow discharge process, obtain the COTTON FABRIC with floride-free waterproofing function.

2. low pressure plasma method for sorting according to claim 1, is characterized in that, in step (1), Cement Composite Treated by Plasma power changes between 60W-140W, and the time regulates within the scope of 60s-300s.

3. low pressure plasma method for sorting according to claim 1, is characterized in that, low pressure plasma collating unit comprises vacuum chamber, radio-frequency power generator, pressure indicator and self-clocking alarm.

4. low pressure plasma method for sorting according to claim 3, is characterized in that, pressure when 20Pa to COTTON FABRIC glow discharge process.

5. low pressure plasma method for sorting according to claim 3, its feature is, passes into helium when pressure is less than 10Pa in vacuum chamber, and cycle charge discharge gas 2 ~ 3 times keeps pressure to open when steady state value 20Pa putting a button afterwards.

6. low pressure plasma method for sorting according to claim 1, is characterized in that, the purity of described t etram-ethyltetravinylcyclotetrasiloxane is 99.00 %.

7. low pressure plasma method for sorting according to claim 1, is characterized in that, helium purity is 99.99%.