Ramkumar and others from Texas Tech University believe that nanomaterials will be the future of non-woven fabrics. They believe that non-woven products play a role in the development of nanotechnology. In 1934 patented cellulose cellulose acetate spinning technology was widely considered the basis of nanotechnology. Print Fabric,Custom Print Fabric,Printed Cotton Fabric,Printed Cloth Material SHAOXING KAIMING TEXTILES CO.,LTD , https://www.sxruiqi.com
Nanotechnology was first applied in the electronics industry. The textile industry has been used lately and has not been widely used so far. Donaldson's nanofiltration equipment and Nano-Tex waterproof splash fabric are small quantities of industrialized products that have entered the market. According to Donaldson personnel, about one-third of all its products contain a nanomaterial. So far, there are about 100 colleges and industrial research institutes around the world that are engaged in the exploration of nanofibers, textiles, and polymers. A number of governments have invested heavily in funds. According to the National Science Foundation, 2005, they invested in nanotechnology. More than 4 billion U.S. dollars. The United States, the European Union, and Japan have taken the lead in this regard. In recent years, there have been some interesting developments in fiber and textile nanotechnology.
Nanofibers
The nanoscale fiber products developed by the laboratory have the advantages of large specific surface area, flexibility, air permeability, microporous structure, light weight, high Young's modulus, and good functionality. At present, there are a few successful batch applications. Examples include filters, liners for chemically-resistant fabrics, tissue scaffolds, and some high-end engineering applications. Fibers with a diameter of 100-500 nanometers are generally regarded as nanofibers.
In 1934, the electronic spinning method invented by Anton Formhals was the pioneer of nanofiber electrospinning of nonwoven fabrics today. Electrospinning is a charged nozzle with a high-voltage electric field. The polymer solution is spun and the solvent evaporates to dry to form a nanofiber web. Strictly speaking, nanofibers are non-woven webs of submicron fibers. Depending on the end use, various polymers, such as natural, synthetic, and biodegradable polymers, can be easily fabricated into nanofiber webs using e-spinning. Thanks to Professor Reneker's work at Akron University, a wave of nanofiber spinning emerged in the 1990s. Doshi opened a nanotechnology company, eSpin Technologies Inc., in Tennessee to mass produce e-spinning nanofibers from a variety of polymers.
Rutledge Group at the Massachusetts Institute of Technology (MIT) conducted basic research on electrospinning and determined the end nozzle diameter of a certain polymer that can spin the corresponding fiber diameter.
Applied to military industry
In addition to filter equipment, functional nanofibers are valued in military research and development due to their potential for chemical and biological weapons resistance. In order to protect soldiers from poison damage and provide the necessary comfort, nanofibers are extremely useful. Nano-fiber lining anti-biological and military uniforms are lightweight, breathable, versatile, and have good chemical resistance, and are resistant to toxic liquids, vapors and smoke.
The Natick Military Center in the United States collaborated with the government, industry, and institutions to explore the practical applications of nanofibers and nanoparticulates in protective clothing. There are some encouraging topics, such as the electrospinning fabric of thermoplastic elastomer polyurethane, which has good performance; it has high elasticity, and it has high strength without further processing or processing. The current tests and developments focus on functional meltblowing and electrospinning; blending nanoscale aluminum and titanium materials into webs and adding other methods to add reactive compounds to fabrics to achieve self-decontaminating properties.
Functional nanofibers with other materials can increase their application value. Nanofibers buried with metal oxides can catalyze organophosphorus chemical weapons agents. Recently, Texas Tech University successfully buried magnesium oxide (MgO) in polymer fibers, carefully controlled the process, and deposited nanoparticles on the surface of the fiber to maximize chemical reactivity and provide better protection against poisoning. . Electrospinning technology can be effectively used to develop honeycomb filter-in-filter polyurethane nanomesh. These filter devices provide filtering capabilities because nano meshes better capture particles.
The Ramakrishna Group of the National University of Singapore and the Defense Technology Agency (DSTA) have collaborated to develop nanofiber biohazard masks that can replace activated carbon with nanofiber mesh materials to trap airborne poisons. They embed nanometal materials and cyclodextrins into nanometer Fibers break down chemical poisons. Initial tests of "paraoxon" with chemical weapon simulants were successful. The ultimate goal is to develop nanofiber military uniforms that can be washed and durable.
At the same time, Prof. Rutledge of MIT and his assistants developed a superhydrophobic e-spun nanomaterial fabric that is affected by the chemical and morphological properties of the fiber surface. These water-repellent nanowebs have a wide range of end uses in protective clothing and biomedical applications. use.
University of Tennessee TANDEC et al. added nanophase Mn (VII) manganese oxide (M-7-0 agent) as a defensive material to the nonwoven. The M-7-0 agent is an environmentally friendly material and is a Lewis acid oxidizer. The main advantage of this kind of non-Woven Fabric cloth is that it can be transported safely, can be made into different shapes according to the end use, has good flexibility, removes chemical weapons, pesticides and industrial toxic materials.
Applied to biomedicine
Prof. Freg of Cornell University and his assistants have developed biodegradable polymers with high specific surface area and hydrophilic materials that can be used for biosensors for drug delivery and insecticide delivery. According to Freg, the high specific surface area of ​​nanofibers has more reactive sites in small-sized fibers.
Donaldson has been at the forefront of nanofiber mesh biomedical applications and has been in the nanofiber business for more than 20 years. In 1981, its Ultra Web nanofiber filter equipment was industrialized and expanded into new applications such as nanofiber cell culture materials and smoke barrier clothing. In 2002, Donaldson established a new team to focus on the new application fields of nanofibers and to encourage cooperative research partners to jointly expand batch applications. Recently, it developed a three-dimensional cell culture medium that mimics extracellular matrix (ECM) in vivo. Biodegradable nanowebs, because of their similarity to the extracellular matrix, can serve as tissue scaffolds. This kind of scaffold makes cells close to each other and grow into a three-dimensional organization. The key factors are mechanical stability, biological compatibility, cell proliferation and cell-matrix interaction. These determine the application of nanofibers in biomedicine.
latest progress
Recent interest in nano-spun fibers has been enormous. Hills has successfully studied homogenous melt-spun fibers with a diameter of 250 nanometers using a sea-island approach. According to it, the fiber strength can reach 3 g/denier and can be coiled for further downstream processing. Hills has developed a 2-0.3 micron sea-island fiber spunbond fabric; it has also been successfully manufactured using the island-sea method. 300 nm diameter nanotubes with a wall thickness of 50-100 nm have been patented. Hills's nanotube fibers can be used to defend against chemical weapons, drug release, micro-scale filtration and micro-level hydraulics (hydraulic devices).
NEC Laboratories Sumio Ijima developed pure multi-layered carbon nanotubes in 1991. Its characteristics are light weight, high strength, good electrical properties and heat resistance. Scientists from the NanoTech Institute at the University of Texas at Dallas (UTD) in the United States, in collaboration with the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia, have made major breakthroughs in spinning multilayer carbon nanotube yarn technology with high strength and good toughness. , extremely soft, conductive heat transfer, can be made of "intelligent" clothing, electrical energy storage, bullet-proof, temperature, porous, very comfortable to wear.
Unprecedented application prospects in nonwovens
One of the reasons why electronic spinning technology fails to popularize industrialization may be that it is difficult to buy industrial-scale machinery and equipment. NanoStatics, Ohio, has developed nano-fibers and nano-materials-containing electrospinning machinery manufacturing technologies that achieve industrial-scale, high-volume production. NanoStatics electronic spinning technology can normally produce 50-100 nanometer diameter fibers, and its nanometer mesh thickness can be in the range of 100 nanometers to 200 micrometers with investment production conditions.
ACON, AG, a Zurich-based scientific consulting firm, estimates that the global nanotechnology market will reach $90 billion in 2015. The adoption of a large number of nanofiber non-woven products will facilitate the production of non-woven fabrics and the textile industry to develop a variety of high-value-added applications and use nanoscience to expand its market share. Collaborative research between the basic industry and industry will enable nonwovens to achieve a win-win situation in future molecular-level technologies. ("Textile and Apparel Weekly")