CN103410001B - Preparation method of self-cleaning cotton fabric based on light-induced polymer free radicals for degrading pollutants - Google Patents

Abstract

The invention discloses a method for manufacturing cotton fabrics based on light-induced macromolecule radical degradation of pollutants, and belongs to the technical field of functional textiles. The present invention utilizes the characteristic that sulfonated polyether ether ketone has high activity to H atoms on organic matter under photoinitiation, selects suitable H donor agent and crosslinking agent, and crosslinks the cotton fabric rich in hydroxyl to form a film. Self-cleaning fabrics that can generate polymer free radicals by light and have the effect of eliminating pollutants. The main steps include: (1) Preparation of photoinitiated free radical polymer composite finishing liquid, which contains sulfonated polyether ether ketone, H donor polymer, crosslinking agent, HCl, etc.; Padding and baking in liquid. The cotton fabric with the function of light-induced degradation of pollutants prepared by the invention has the functions of antibacterial, pesticide degradation, pigment degradation, etc., and can be used for daily clothing, medical fabrics and household fabrics, etc., and has wide application prospects.

Description

Self-cleaning cotton fabric preparation method for photo-induced macromolecule free radical degradation of pollutants

technical field

The invention belongs to the field of functional textiles, in particular to a method for preparing self-cleaning cotton fabrics based on light-induced macromolecule free radical degradation of pollutants.

Background technique

Smart surfaces with self-cleaning functions have a very broad application prospect in daily life and industry. Its application in the fields of glass, ceramics, automobiles and textiles can reduce environmental pollution and water and electricity consumption caused by cleaning. Therefore, under the premise that the world attaches great importance to environmental and energy issues, the research on self-cleaning surfaces has become one of the hot issues that people pay attention to. In the textile field, self-cleaning fabrics with pollutant degradation function can not only alleviate the environmental and energy problems caused by washing, but also effectively shield and eliminate various environmental pollution such as bacteria, viruses, pesticides, stains, etc. Therefore, cotton fabrics with pollutant degradation function can be widely used in daily clothing, biochemical protective clothing, medical care, food processing, environment, farms, military and other aspects.

Self-cleaning fabrics with pollutant degradation function are currently mainly prepared based on the principle of photocatalysis. For example, in the field of functional textiles, Xin Haozhong and Walid A. Daoud from Monash University in Australia have prepared polyester fabrics and cotton fabrics. The anatase nano-TiO ₂ crystalline film can improve the antibacterial performance of the fabric, can effectively degrade Neolan blue 2G dye, and has self-cleaning effect; Hurren of Deakin University prepared a thin layer of TiO ₂ on the surface of wool fabric, and the results showed that the The surface of wool fabric has a self-cleaning effect of catalytic degradation of red wine stains; Wang Chaoxia et al. in China have studied the self-cleaning performance of rare earth ion thulium (Tm) doped TiO ₂ modified cotton fabrics, and the results show that capsanthin stains can be removed when the light is 3 hours. The degradation rate of the substance is about 94%. In 2011, Walid A. Daoud et al. reviewed the research on the self-cleaning of polymer fibers through nanotechnology (mainly nano-TiO ₂ ) in the past five years, and pointed out some problems in this method, such as inorganic TiO ₂ particles and The fastness of fiber bonding is not good, it is easy to fall off, the fiber feels bad, and it is difficult to disperse evenly on the surface of the fiber. In addition, Wang Jianqing of Donghua University et al ^] believe that the self-cleaning condition of this type of photooxidant needs to be eliminated under continuous sunlight, so this type of product is more suitable for outdoor occasions, such as exterior wall coatings, curtain wall glass, etc. Therefore, new ideas are needed to develop high-performance, low-cost self-cleaning surfaces suitable for polymer fiber materials.

Contents of the invention

In order to solve the above-mentioned technical problems existing in the prior art, the present invention provides a kind of self-cleaning cotton fabric preparation method based on light-induced macromolecule radical degradation pollutants, comprising the following steps:

(1) Prepare photo-induced free radical polymer composite finishing solution:

Each L of finishing solution is composed of the following components: sulfonated polyetheretherketone 2.5~15g; H donor polymer 5~17.5g; crosslinking agent 1~10wt%; adding HCl to adjust the pH to 2~5;

Preparation steps: Dissolve the sulfonated polyether ether ketone in water, heat to 50°C in an ultrasonic environment to dissolve; weigh an appropriate amount of H donor polymer, dissolve in water to fully swell, heat to 85°C to dissolve, and At 70°C, stir the two solutions thoroughly, add an appropriate amount of HCl, and add an appropriate amount of cross-linking agent after 5 minutes;

(2) Cotton fabric padding and baking:

Padding: The cotton fabric is soaked in the above-mentioned finishing solution by a pad car for 30~50 minutes, and then the padding is carried out, and the padding rate is 70~110% after dipping and padding;

Baking: After padding, the cotton fabric is pre-baked in an oven at 80-90°C for 20-40 minutes, and then baked at 130-160°C for 60-240 s.

Further, the sulfonation degree of the sulfonated polyether ether ketone is 70-90%.

Further, the H donor polymer is polyethyleneimine or polyvinyl alcohol.

Further, the crosslinking agent is epichlorohydrin or glutaraldehyde.

The present invention has following characteristics:

(1) The SPEEK used in the present invention has excellent mechanical properties, heat resistance and chemical resistance, and is usually used in the fields of fuel cells, ultrafiltration membranes, reverse osmosis membranes, biomedical materials, etc., and polymers such as PVA and PEI It can form a soft and light-transmitting composite film, so it is suitable for preparing functional textiles on the surface of fabrics.

(2) When the photoself-cleaning polymer proposed in the present invention is applied to cotton fabrics, it can be firmly combined with the -OH groups on the cotton fiber macromolecules through crosslinking or grafting, so that its fastness is high without affecting the fiber material Excellent hand feel, gloss and other physical properties; overcome the problems of poor fastness of inorganic photocatalyst particles and fibers, easy to fall off, poor fiber feel, and difficulty in uniform dispersion on the fiber surface. Therefore, compared with the current method of using inorganic nanoparticles (such as TiO ₂ ) to achieve self-cleaning of the fiber surface, it has certain characteristics and advantages.

(3) The active free radicals produced by the polymer system in the present invention are weaker than the hydroxyl radicals (·OH) produced by nano _-Ti2O , which is not only safer for the human body, but also does not cause excessive damage to the polymer film and fibers , affecting the durability of the membrane and the strength of the fiber

(4) The present invention adopts a green path for pollutant purification under mild conditions, therefore, it may also be used for the treatment of pollutants in waste gas and wastewater through appropriate improvements.

(5) For the first time, sulfonated polyether ether ketone (SPEEK) was used to prepare textiles with pollutant degradation function. Compared with inorganic photocatalysts, SPEEK, as an organic polymer, has a higher compatibility.

Detailed ways

The present invention will be further described below.

In the self-cleaning fabric preparation method based on the photo-induced macromolecule active free radical digestion of pollutants of the present invention, sulfonated polyetheretherketone (SPEEK) is used to prepare textiles with pollutant degradation function for the first time. This is because SPEEK contains BP groups, which can form n, π* excited triplet states under photoinitiation, and have high activity on hydrogen atoms in other compounds, such as when it coexists with polyvinyl alcohol (PVA), PVA As an H atom donor, two polymeric alcohol radicals can be formed under photoinitiation, and the reaction process is shown in the following formula:

(1)

(2)

The α-hydroxy radical of PVA in formula (2) can also react with the second polybenzophenone group to form a new SPEEK radical. Due to the slow coupling reaction between the generated SPEEK free radicals, the free radicals have a long lifespan at room temperature; therefore, once the polymer free radicals are formed after photoinitiation, they can decompose pollutants for a long time effect. If under the condition that O ₂ participates, O ₂ can be reduced by one electron to form highly oxidative active superoxide anion free radical O ₂ ^- and protonated HO ₂ free radical:

(3)

HO ₂ · H ⁺ + O ₂ ^- (4)

Therefore, the above products can more effectively oxidize and degrade the pollutants on the surface of the material, and have a better self-cleaning effect; moreover, their oxidative properties are weaker than the hydroxyl radicals (OH) produced by nano-Ti ₂ O, not only It is safer for the human body, and will not cause excessive damage to the polymer film and fiber, affecting the durability of the film and the strength of the fiber. On the other hand, the redox potential of BP free radical anion C(Φ) ₂ O ^- is 2.0V, which is higher than that of SPEEK free radical, and the reactivity with organic pollutants will be stronger; BP free radical Negative ions can be formed in the presence of secondary amines ( _R2NH ):

(5)

Therefore, choosing a suitable composite system (such as polyethyleneimine PEI) can form a highly active BP group-containing free radical anion polymer on the surface of the fiber:

[RR'C=O] _m + [R ₁ NHR ₂ ] _n + hv →[RR'C·O ^- ] _m + [R ₁ R ₂ NH ⁺ ] _n (6)

In summary, it is feasible to prepare self-cleaning fiber fabrics by photogenerating active organic polymers to decompose pollutants.

Example 1

Manufacturing method of self-cleaning cotton fabric based on photoinduced macromolecule free radical degradation of pollutants:

Preparation of degradable pollutant cotton fabric:

1) Add 15g of sulfonated polyether ether ketone with a sulfonation degree of 70.3% to 500mL of deionized water, and heat it to 50°C under an ultrasonic environment to dissolve;

2) Add 5g polyvinyl alcohol into 500mL deionized water, swell in cold water for 2 hours, then heat to 85°C and stir to dissolve;

3) Add the dissolved sulfonated polyether ether ketone into the dissolved polyvinyl alcohol, heat to 70°C, add HCl to adjust the pH to 2.3, add 6wt% crosslinking agent glutaraldehyde after 5 minutes, and stir vigorously 5min, make 1L finishing solution, and cool to room temperature;

4) Soak a square piece of cotton cloth in the cooled finishing solution, control the bath ratio to 1:20, soak for 50 minutes and squeeze the liquid, one dip and one rolling, the liquid rolling rate is 70%, pre-baked at 80°C for 40 minutes, 160°C Bake for 120s, wash with water, and dry at 80°C.

Performance testing of cotton fabrics

Pollutant degradation performance

Soak the treated cotton cloth in an aqueous solution of simulated pollutant methyl orange with a concentration of 100 mg/L, take it out and dry it after 5 minutes, and measure its K/S value with a Datacolor SF600 computer color measuring and matching instrument; Irradiate under ultraviolet light for 1h, then measure its K/S value. Calculate K/S value change rate R

Washability

Put the cotton fabric in soap solution with 5g/L soap flakes and a bath ratio of 1:50, soap it at 40°C for 30 minutes, then wash it in cold water for 10 minutes, dry it, and measure its pollutant degradation performance.

Fabric stiffness, smoothness, softness test

Cut a circular sample with a diameter of 10cm, weigh its mass, and measure its thickness. Use a Nucybertek Phabromet fabric style meter to test its hardness, smoothness, and softness. Three samples are tested for each sample, and three samples are tested. The average of the test results of the sample is the test result of the sample.

Fabric Whiteness Test

Fold the sample to be tested into 4 layers, and measure it on the WSD-3C automatic whiteness meter. Take 3 different points on the coated surface of a piece of fabric to measure, and take the average value of Hunter whiteness measured for 3 times. The whiteness value of the sample.

Fabric breaking strength test

Test according to the standard GB/T 3923.1-1997 "Textile Fabric Tensile Properties".

Example 2~Example 5

Change the amount of SPEEK, H donor, SPEEK sulfonation degree, pH value, crosslinking agent dosage, impregnation time, extrusion rate, pre-baking temperature and time, and baking temperature and time in each 1L finishing solution.

Table 1, the technological formula of each embodiment

The performance test of the cotton fabric after table 2, each embodiment process

Finally, it should be noted that the above examples are only some specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and many variations are possible. All deformations that can be directly derived or associated by those skilled in the art from the content disclosed in the present invention should be considered as the protection scope of the present invention.

Claims (3)

1. The self-cleaning cotton fabric preparation method based on light-induced macromolecule free radical degradation pollutant, comprises the steps: (1) Prepare photo-induced free radical polymer composite finishing solution: Each liter of finishing solution is composed of the following components: sulfonated polyether ether ketone 2.5~15g; H donor polymer 5~17.5g; crosslinking agent 1~10wt%; The degree of sulfonation of polyether ether ketone is 70~90%; Preparation steps: Dissolve the sulfonated polyether ether ketone in water, heat to 50°C in an ultrasonic environment to dissolve; weigh an appropriate amount of H donor polymer, dissolve in water to fully swell, heat to 85°C to dissolve, and At 70°C, stir the two solutions thoroughly, add an appropriate amount of HCl, and add an appropriate amount of cross-linking agent after 5 minutes; (2) Cotton fabric padding and baking: Padding: The cotton fabric is soaked in the above-mentioned finishing solution by a pad car for 30~50 minutes, and then the padding is carried out, and the padding rate is 70~110% after dipping and padding; Baking: After padding, the cotton fabric is pre-baked in an oven at 80-90°C for 20-40 minutes, and then baked at 130-160°C for 60-240 s. 2. The method for preparing self-cleaning cotton fabric based on photopolymer free radical degradation of pollutants according to claim 1, characterized in that: the H donor polymer is polyethyleneimine or polyvinyl alcohol. 3. The self-cleaning cotton fabric preparation method based on photopolymer free radical degradation pollutants according to claim 1, characterized in that: the crosslinking agent is epichlorohydrin or glutaraldehyde.