CN1190546C - Method for preparing nano particle modified chemical fibre - Google Patents

Abstract

A preparation method of nanoparticle modified chemical fiber, which is characterized in that the surface treated nanoparticle is added to the coagulation bath, preheating bath or extraction bath of wet spinning or dry-wet spinning in a certain proportion, and the High-speed stirring dispersion and ultrasonic dispersion to prepare evenly dispersed bath liquid of nanoparticles to replace the coagulation bath, preheating bath or extraction bath of wet spinning or dry-wet spinning, and the nanoparticles diffuse into the fiber by means of diffusion In the micropores formed after solvent, and then after stretching and other post-processing processes to make fibers with uniformly dispersed nanoparticles. In the nano particle modified chemical fiber prepared by the method of the invention, the nano particle is dispersed in the fiber at the nanometer level, thereby improving the tensile performance of the fiber. The preparation method is relatively simple, the production cost is low, and it is convenient for industrial implementation.

Description

Preparation method of nanoparticle modified chemical fiber

technical field

The invention relates to a preparation method of chemical fiber, in particular to a preparation method of chemical fiber modified by nano particles.

Background technique

Nanoparticles have a large specific surface area, and the number of surface atoms, surface energy and surface tension increase sharply with the decrease of particle size. Properties, magnetic properties, optical properties and electrical properties are different from conventional particles. Adding nanoparticles into chemical fibers will endow these functions into the fibers and make nanoparticle-modified chemical fibers. Nanoparticles with different properties can be used to develop various functional fibers such as antibacterial, flame retardant, anti-ultraviolet, far-infrared, negative oxygen ion health care, antistatic and electromagnetic shielding, or improve the heat resistance or mechanical properties of fibers.

The easiest way to prepare nanomaterial-modified chemical fibers is the post-finishing method. like:

In Chinese patent CN93114055, fabrics such as cotton, hemp, silk, and synthetic fibers are soaked in fluoride, organosilicon compound, surfactant, adhesive, nano-ceramics, water and other mixed solutions, and after removing excess solution, soak them in 50 Drying and shaping at ~200°C to make fabrics with waterproof, dustproof, oil-repellent, and UV-resistant properties; in Chinese patent CN00132606, nano tourmaline particles, far-infrared powder, emulsifiers and adhesives are first formulated in a certain proportion The finishing solution, and then use the finishing solution to pad, coat or spray the fabric to make a fabric with negative oxygen ion far-infrared health care function.

However, the above-mentioned post-finishing technology has the problem of coagulation and adsorption stability of nano ultrafine particles, and the treated fabric will affect its use function due to washing. To prepare permanently functional nano-modified fibers, it is necessary to fill the interior of the fibers with nanoparticles.

The most commonly used method for filling nanoparticles into fibers is the blend spinning method, including melt blend spinning method and solution blend spinning method.

Melt blending spinning is to uniformly disperse nanoparticles in polymer melt, and then spin and draw on traditional spinning equipment to obtain nanoparticle-modified fibers without adding other equipment. For example, in Chinese patent CN01108688, surface-treated nanoparticles and polyethylene terephthalate are co-ground in a special reactor, and then melt-blended with polyethylene terephthalate in a certain proportion to prepare polyethylene terephthalate. Ethylene phthalate/nano-composite fiber; in Chinese patent CN02111209, polyester or modified polyester, accelerant, and nano-powder are ternally blended and melt-spun to make antistatic nano-composite polyester fiber.

Because nanoparticles are easy to agglomerate and the melt viscosity of the polymer matrix is relatively large, it is difficult to achieve nanoscale dispersion of nanoparticles in the polymer matrix by mechanical blending alone in the above method, thereby affecting the spinning, spinning and blending of the blend. tensile properties.

Solution blending spinning is to uniformly disperse nanoparticles in the spinning solution, and then perform spinning, solvent removal, and drafting processes to obtain nanoparticle-modified fibers. For example, in the Chinese patent CN02148597, first surface treat the nanoparticles and evenly disperse them in the spinning solvent of ultra-high molecular weight polyethylene (UHMWPE), then add UHMWPE powder to swell and dissolve to make a spinning solution, and then spin , UHMWPE fibers modified by nano-particles are made by stretching, and the mechanical modulus of the fibers can be increased by 20-70% on the original basis. In the Chinese patent CN01128377, nano powder materials with related functions are uniformly mixed in the artificial viscose solution carrier, and are processed into functional artificial viscose fibers with regulating effect on human skin through spinning.

Since nanoparticles are easy to agglomerate, even after surface treatment and ultrasonic dispersion, it is inevitable that there will be agglomerates of nanoparticles in the spinning solution, which will affect its spinnability and stretchability.

In order to effectively solve the problem of uniform dispersion of nanoparticles in the polymer body, a new method of in-situ polymerization and compounding has been proposed, that is, to load highly dispersed nanoparticles with catalytically active components, and then Polymerization was carried out on the surface to prepare in situ composites. For example, Chinese patent CN1255510A and U.S. patent USP6444742 disclose a nanoscale composite material of polyolefin and clay, which is composed of 40-99.9% by weight of polyethylene and 0.1-60% by weight of argenite clay. The transition metal compound of the nanoscale clay is used as a catalyst, and the organoaluminum compound is used as a cocatalyst to carry out in-situ polymerization of olefins, and the prepared composite material has excellent mechanical properties and thermal properties. Chinese patent CN01142857 discloses a preparation method of nano-composite polyester. First, a mixed solution of nano-zinc oxide, nano-barium sulfate, ethylene glycol and terephthalic acid is prepared in a certain proportion, and then a catalyst and a stabilizer are added to carry out polymerization. material to make nanocomposite polyester. The in-situ polymerization and compounding method can make nanoparticles uniformly dispersed in the polymer matrix, but this method is cumbersome, the cost of the obtained composite material is high, and the spinning performance of the obtained nanocomposite polymer needs to be further studied.

Contents of the invention

The technical problem to be solved in the present invention is to disclose a relatively simple method for preparing nanoparticle-modified chemical fibers, so as to overcome the above-mentioned defects in the prior art and meet the needs of related fields.

Technical concept of the present invention is such:

The fibers mentioned in the present invention are limited to fibers spun by wet or dry-wet methods, which are characterized in that the surface-treated nanoparticles are added to the coagulation bath of wet spinning or dry-wet spinning in a certain proportion, In the preheating bath or extraction bath, carry out high-speed stirring dispersion and ultrasonic dispersion for a certain period of time to prepare a bath liquid in which nanoparticles are evenly dispersed, to replace the coagulation bath, preheating bath or extraction bath of wet spinning or dry-wet spinning, By means of diffusion, the nanoparticles diffuse into the micropores formed after the fiber is removed from the solvent, and then the fibers are made into uniformly dispersed nanoparticles through stretching and other post-processing procedures. Depending on the addition of nanoparticles, it can be made into various functional fibers with antibacterial, flame retardant, anti-ultraviolet, far-infrared, negative oxygen ion health care, antistatic and electromagnetic shielding, or improve the heat resistance and mechanical properties of the fibers.

The method of the present invention comprises the following steps: wherein, unless otherwise specified, the proportions of raw materials are all proportions by weight.

(1) Preparation of evenly dispersed bath solution of nanoparticles:

Put the surface-treated or modified nanoparticles or their mixture, and coagulation bath, preheating bath or extractant and other media into the container at a ratio of 0.5 to 5:100, stir at high speed for 10 to 30 minutes, and then perform ultrasonic treatment for 20 to 30 minutes. 40min, the nanoparticles are uniformly dispersed in the dispersion medium, and the nanoparticle uniformly dispersed bath liquid is obtained;

Said nanoparticles are zero-dimensional nanoscale inorganic particles with an average particle size of 10-100nm, preferably nano-silver, silicon dioxide, titanium dioxide, aluminum oxide, zinc oxide, calcium carbonate, barium sulfate, natural tourmaline or strange ice stone One or a mixture of powders;

The term "surface treatment or modification" refers to covering the surface of nanoparticles with surfactants in a solvent to give new properties to the surface of the particles, such as titanates, silanes, etc. in isopropanol, ethanol or acetone. Surfactants such as coupling agent, aluminate, stearate or laurate cover the surface of inorganic nanoparticles, and the method provided in Chinese patent CN02148597 can be used to treat or modify the surface of the nanoparticles. The main purpose is to Prevent the agglomeration of nanoparticles and increase their dispersibility in the dispersion medium.

The medium used in the coagulation bath, preheating bath or extractant is a conventional medium, which has been reported in this general technical literature.

(2) Preparation of chemical fibers modified by nanoparticles:

The fiber obtained by wet spinning or dry-wet spinning is placed in the dispersion bath of step (1), and the nanoparticles are diffused into the micropores formed after the fiber is desolvated under ultrasonic or standing state, and then passed through After stretching and other post-processing processes, fibers with uniformly dispersed nanoparticles are made;

The chemical fibers include polyacrylonitrile fibers, viscose fibers, ultra-high molecular weight polyethylene fibers, polyvinyl alcohol fibers, and aramid fibers;

The residence time of the fiber in the coagulation bath, preheating bath or extraction bath in the ultrasonic state is 0.2-5 minutes, while the residence time of the fiber in the coagulation bath, preheating bath or extraction bath in the static state is 3-30 minutes.

The key technology of the present invention is to make nanoparticles diffuse into the micropores formed after the solvent is removed from the fiber by means of diffusion. Since the size of the micropores formed by removing the solvent from the wet spinning or dry-wet spinning fiber is generally nanoscale, the coagulation bath, pre- Even if there are nanoparticle aggregates in the heating bath or extraction bath, the nanoparticle aggregates are not easy to diffuse into the interior of the fiber. Therefore, the nanoparticle-modified chemical fiber prepared by the method of the present invention can achieve nanoscale dispersion of the nanoparticle in the fiber, thereby improving the tensile performance of the fiber. The preparation method is relatively simple, the production cost is low, and it is convenient for industrial implementation.

Description of drawings

Figure 1 is a scanning electron micrograph of a section of a polyethylene fiber containing nanoparticles.

Detailed ways

Example 1

Add the surface-treated nano-silica and xylene into a container with an ultrasonic generator at a ratio of 1:100 and stir at a high speed for 20 minutes to make an extract with evenly dispersed nanoparticles. Put the polyethylene jelly fiber in In it, the extraction was carried out twice for a total of 20 minutes in a static state, and then dried at room temperature. The dry jelly fiber is stretched 12 times at 100°C, 2 times at 110°C, and 1.4 times at 120°C. The strength of the obtained fiber is 30.5cN/ dtex, the modulus is 1720cN/dtex, and the elongation at break is 3.31%. However, the polyethylene jelly fiber is extracted under the same conditions in an extraction bath not containing nanoparticles and then dried and stretched under the same conditions. The fiber strength obtained is 29.6cN/dtex, and the modulus is 1170cN/dtex. The elongation was 3.83%. The SEM photo of the cross-section of the fiber after primary stretching is shown in Fig. 1 .

Example 2

Add 2 parts each of surface-treated nano-tourmaline particles and nano-titanium dioxide particles to 98 parts of an aqueous solution containing 3% sodium thiocyanate, and stir at high speed under ultrasonic conditions for 20 minutes to prepare a preheating bath for uniform dispersion of nanoparticles.

The polyacrylonitrile primary fiber coming out of the coagulation bath enters the above-mentioned preheating bath, the bath temperature is 55°C, stretched 1.5 times under the ultrasonic state, the fiber stays in the preheating bath for 1min, and then carries out secondary stretching and water washing and other post-treatment processes to make acrylic fibers containing nanoparticles. After testing, the average number of negative oxygen ions released by the final product is 150/cm ³ , the far-infrared emission rate is 83%, the bacteriostatic rate to Escherichia coli is 81%, and the bacteriostatic rate to Staphylococcus aureus is 77% .

Claims (8)

1. the preparation method of a nanometer particle-modified chemical fibre is characterized in that, comprises the steps:

(1) will be through the nano particle after surface treatment or the modification or its mixture, with coagulating bath, pre-heating bath or extractant medium, add in the container and carry out high-speed stirred, carry out sonicated again, nano particle is evenly disperseed in decentralized medium, obtain nano particle and evenly disperse body lotion;

(2) wet spinning or as-spun fibre that dry-wet spinning obtains are placed the dispersion body lotion of step (1), under ultrasonic or static condition, make nano particle diffuse into fiber and desolventize in the back micropore that forms, adopt conventional postprocessing working procedures to make the homodisperse fiber of nano particle then.

2. the preparation method of nanometer particle-modified chemical fibre according to claim 1, it is characterized in that, will be through the nano particle after surface treatment or the modification or its mixture, with coagulating bath, pre-heating bath or extractant medium, by 0.5～5: carry out high-speed stirred 10～30min in the 100 adding containers, carry out sonicated 20～40min again, described raw material umber is the weight fraction ratio.

3. the preparation method of nanometer particle-modified chemical fibre according to claim 1 is characterized in that, said nano particle is a zero-dimension nano level inorganic particulate.

4. the preparation method of nanometer particle-modified chemical fibre according to claim 3 is characterized in that, the nano particle average grain diameter is 10～100nm.

5. the preparation method of nanometer particle-modified chemical fibre according to claim 3, it is characterized in that nano particle is Nano Silver, silica, titanium dioxide, aluminium oxide, zinc oxide, calcium carbonate, barium sulfate, crude tourmaline or very ices a kind of or its mixture in the stone powder.

6. the preparation method of nanometer particle-modified chemical fibre according to claim 1, it is characterized in that described chemical fibre comprises a kind of in polyacrylonitrile fibre, viscose, ultra high molecular weight polyethylene fiber, vinal or the aramid fiber of wet spinning or dry-wet spinning.

7. according to the preparation method of each described nanometer particle-modified chemical fibre of claim 1～6, it is characterized in that fiber time of staying in coagulating bath, pre-heating bath or extraction bath is 0.2～5min under the ultrasonic state.

8. according to the preparation method of each described nanometer particle-modified chemical fibre of claim 1～6, it is characterized in that fiber time of staying in coagulating bath, pre-heating bath or extraction bath is 3～30min under the static condition.

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