Nanomaterials have been used to produce different types of leather

Leather finishing is a very important operation in the manufacture of leather, in which a variety of different chemicals are used. The introduction of nano-materials in leather finishing has revolutionized the leather industry, and nanomaterials have been used to produce a variety of different types of leather to meet the diverse needs of consumers. The purpose of this study is to combine leather science and nanotechnology to achieve superior performance with superior characteristics. TiO2 nanoparticles are widely used in many fields, such as antibacterial agents, super-hydrophilic materials, water vapor permeable materials, solar cells, ultraviolet absorbers, catalytic materials, plastics, fibers, controlled release, pigments, thermal insulation materials, coating Layer adhesive, self-cleaning coating, scratch resistant anti-wear material, etc. The use of nanomaterials in leather finishing has a strong durability that helps the leather withstand the test of time.

 

(1) TiO2 nanoparticles show better adhesion after coating on leather. The improvement in adhesion is due to the fact that the TiO2 nanoparticles used in the finishing formulation promote the reactivity of the binder, other finishing aids and the leather matrix due to the greater specific surface area.

(2) Adhesion is also related to the interfacial force. The polar molecules of the binder are in closer contact with the nano-TiO2 particles, promoting interatomic and intermolecular forces, resulting in better adhesion, strength, and diffusivity.

(3) The very large specific surface area of the nano TiO2 particles contributes to the adsorption of other coating materials and can increase the reaction performance. And the nano-TiO2 particles can enter the gap between the leather fibers to have a strong interaction with the leather fibers to improve the adhesion performance.

(4) The use of TiO2 nanoparticles in the finishing formulation gives the leather better physical properties, good sensory properties (the coating gloss is medium with nano-TiO2, the leather gloss is higher without using TiO2 nanoparticles) and better Chemical properties. Nano-TiO2 provides better hiding performance, filling performance and bonding performance (the best nano-TiO2 dosage is 0.1~2 g/L).  Select nanoparticle companies from https://www.hwnanomaterial.com

Transparent Thermal Insulation Nano Materials

Nano thermal insulation coating can effectively block infrared and ultraviolet rays in sunlight. When sunlight penetrates the glass and enters the room, it can block more than 99% of ultraviolet rays and block more than 80% of infrared rays. Moreover, its heat insulation effect is very good, can make the indoor temperature difference 3-6˚C, can keep the indoor cool air.

Nano thermal insulation coating is also a very environmentally friendly material, mainly because the coating film does not contain benzene, ketone and other ingredients, nor does it contain other harmful substances. It is truly green and environmentally friendly and meets international environmental quality standards.

There are three transparent Thermal Insulation Nano Materials

1. CS0.33WO3 Cesium-doped tungsten oxide nanoparticles
CS0.33WO3 Cesium-doped tungsten oxide nanoparticles(Cesium tungsten bronze )transparent nano thermal insulation coating stands out from many transparent thermal insulation coatings due to its environmental friendliness and high thermal insulation characteristics, and currently has the best thermal insulation performance.

2. ITO nanoparticles
Nano-ITO (In2O3-SnO2) has excellent visible light transmittance and infrared blocking characteristics, and is an ideal transparent thermal insulation material. Since indium metal is a scarce metal, it is a strategic resource, and indium raw materials are expensive. Therefore, in the development of transparent heat-insulating ITO nanoparticles coating materials, it is necessary to strengthen process research to reduce the amount of indium used on the premise of ensuring the transparent heat-insulating effect, thereby reducing production costs.

3. Nano ATO
Nano-ATO antimony-doped tin oxide coating is a kind of transparent thermal insulation coating material with good light transmittance and thermal insulation performance. Nano antimony tin oxide (ATO)  has good visible light transmittance and infrared barrier properties, and is an ideal thermal insulation material. The method of adding nano ATO powder antimony to the coating to make a transparent thermal insulation coating can effectively solve the thermal insulation problem of glass. Compared with similar products, it has the advantages of simple process and low cost, and has extremely high application value and broad application.

Get more  tansparent thermal insulation Nano materials  from www.hwnanomaterial.com quickly!

Nano silver wire is used for transparent conductive film

Characteristics of nano silver wire:

1. Silver nano wire has high specific surface area, electrical conductivity and thermal conductivity.
2. Nano silver wire has surface plasmon effect: Surface plasmon refers to the electron density wave propagating along the metal surface generated by the interaction between freely vibrating electrons and photons that exist on the metal surface.
3. Silver is a good conductor of electricity, with low resistivity and high conductivity. Applying nano-silver wires to the conductive layer will draw out the collected current, which can reduce energy loss compared with TCO semiconductors.
4. If nano silver wires with a particle size smaller than the incident wavelength of visible light are used, the silver wires can be arranged very densely, and this technology can increase the current collecting area of ​​the silver electrode of the solar cell. It does not block the transmission of light, and at the same time, it can fully absorb light energy by taking advantage of the characteristics of light diffraction.

For transparent conductive film applications:
Due to its nanostructure size effect, nano silver wire has the characteristics of good conductivity, excellent light transmittance, flexibility and wide source of raw materials. The flexible TCF prepared with nano silver wires has the advantages of high transparency, low square resistance, good flexibility, low price, simple process, etc., and is considered to be the next generation of new materials in the field of flexible transparent conductive films.
After years of development, the preparation methods of nano silver wire flexible transparent conductive film mainly include spraying method, spin coating method, Meyer rod coating method and screen printing method. According to different manufacturing methods, the addition amount is different.
AgNWs flexible TCF is favored by the optoelectronic industry due to its excellent optical properties, electrical conductivity and flexibility, and is a new direction for industrial development.
In addition to the excellent conductivity of silver, nano-silver wires also have excellent light transmittance and flexibility due to the nano-level size effect, which provides the possibility to realize flexible, bendable LED displays, touch screens, etc., and A lot of research has applied it to thin-film solar cells. In addition, due to the large aspect ratio effect of silver nanowires, it also has outstanding advantages in applications such as conductive adhesives and thermally conductive adhesives.

The length of the nano silver wire produced by our Hongwu Nanomaterials Company is generally greater than 20 microns, and other lengths can also be customized. If you are interested in this, welcome to consult us.

Related products: metal nanowiresilver  nanopowder

Nano Au for Biomedical Applications

The biomedical field is a brand-new research field formed by integrating the methods and theories of medicine, biology and other related disciplines. Its research contents include bio-medicine, clinical applied chemistry, cytology and immunology, etc. With the rapid development of technology, many cutting-edge research and inventions in hot areas have played an important role in the field of bio-medicine, such as digital holography, virtual reality, and nanotechnology. It can be said that bio-medicine is an important area related to human beings. Studies have shown that surface-modified nano-gold particles can play a very important role in cell imaging, drug carriers, and many other aspects, its performance is closely related to the structure of nano-gold composition, morphology, size and size. More attention is paid to the appearance of gold nano structures such as rods and spheres.

 

Nanomaterials are materials in which at least one dimension in the three-dimensional space is in the nanoscale range or consists of them as basic units. Nano gold is a kind of nano material and is a gold nano particle with a diameter of 1-100nm. Nano-gold particles play an important role in molecular detection, photo-thermal therapy, tumor diagnosis, and green catalysis. In the following, I will give a detailed review of the field of bio-medicine.

 

  1. Application in bio-moleculardetection and identification

The emergence of nano gold immunolabeling technology in 1971 made it possible to see the great potential of nano gold as an immunological marker. After decades of continuous development, the immunolabeling technology using nanogold as a marker has basically matured. Has become one of the four major immunolabeling technologies. With the advancement of science and technology, people have a deeper understanding of the physicochemical properties of Gold nanoparticles dispersion , thus further expanding the biometric detection technology using nano gold as a marker. At present, nanogold is mainly used in biological detection to detect nucleic acids and proteins. Based on its unique surface plasmon resonance effect, catalytic properties, and high-density properties and other physicochemical properties, nano gold has unparalleled advantages in other areas of biological detection, and it has great potential for early diagnosis of tumors.

 

  1. Application in cell imaging and photothermotherapy

The strong scattering of nano gold particles was first used by researchers in the field of nano gold cell imaging and is still the most commonly used nano gold cell imaging method. As long as the diameter of the nano gold particles is greater than 20nm, it can be easily observed in a dark field scattering microscope. Compared with common fluorescent groups, nano gold particles can stably scatter light for a long time without being bleached. At the same time, due to the surface plasmon resonance effect of the nano-gold particles, the molecular electromagnetic field signal will be enhanced if it is within the nano gold surface or within 10 nm from the nano gold surface. Through the extraction of these enhanced electromagnetic field signals, Can be applied to bio-imaging technology. Because nano gold’s two-photon luminescence imaging technology has a much higher signal-to-noise ratio than dark-field microscopy, it has a very high potential for intracellular imaging. In addition, nano-gold particles can produce high thermal behavior by absorbing near-infrared light, a feature that makes it play a significant role in photothermal therapy in medicine.

 

  1. Application in drug delivery and controlled release

The specific surface area of ​​nano gold is relatively large, and its surface is easily modified. The drug can easily bind to the nano gold surface after chemical bonds and non-chemical bonds, thereby forming a nano gold drug-loading system. The drug-loading system formed by nano gold has the characteristics of increasing drug solubility, increasing cytotoxicity, and increasing drug stability. Currently, nano gold has been widely used in various fields of bio-medicine as a carrier for various types of drugs. The use of nano gold as a drug carrier can both protect the drug, increase the activity of the drug, reduce the amount of the drug used, and reduce the medical cost.

Related Tags: Nano gold colloid  Nano Gold dispersion

Carbon nanotubes are used in batteries

Lithium iron phosphate power cell is the most potential lithium-ion power battery for electric vehicles in the market, which has the advantages of good safety, long cycle life, and high energy density. However, lithium iron phosphate has poor electrical conductivity and conductive agent must be added to improve its conductivity. Most commonly used conductive agents are carbon black and graphite, which is cheap. However, in the process of multiple charging and discharging, the expansion and contraction of graphite materials reduces the contact between graphite particles, increases the gap, and even separates from the collector fluid and no longer participates in the electrode reaction. Therefore, the choice of conductive agent has an important role in improving battery performance.
At present, carbon nanotubes(CNTs) have gained wide attention in the application of conductive agents due to their excellent physical and chemical properties. The conductive mechanism of carbon nanotubes is that because they belong to one-dimensional nanomaterials, the length-diameter ratio is relatively large, which is good for the formation of conductive networks, and can improve the bonding between active materials and their collective flow, also it play the role as a physical adhesive. At the same time, it has excellent mechanical properties and chemical inertia, and it also has good thermal conductivity. It can improve the specific capacity and cycle life of the battery and improve the high temperature performance. It is an ideal new type of conductive material for lithium ion batteries.
In the experiment, multi-wall carbon nanotubes were applied to the positive and negative poles of lithium iron phosphate batteries respectively, and different tired batteries were prepared. The conventional performance and doubling rate were tested, and they were compared with the cores prepared by ordinary conductive carbon black. The test results show that, The electric core of high-conductive multi-wall carbon nanotubes added to the carburetor nanotubes has better conventional performance and double discharge performance than the conventional core, and the double discharge effect of both positive and negative poles is the best, followed by the addition of negative poles. The addition of MWCNTs to the negative electrode also shows the same situation. After the negative electrode capacity increases, it can embed more lithium ions when charging, which is conducive to the increase of discharge capacity, and because multi-walled carbon nanotubes have better electronic transport capabilities. In addition, more continuous conductive networks are formed in the click, which reduces the number of active substance particles encouraged. Also, the positive pole is added. The carbon nanotube, in high purity, is easy to disperse, has a low resistivity and can reach a resistivity of 650 μΩ. M, which is very suitable for battery use.
Multi-wall carbon nanotubes for lithium iron phosphate batteries
The addition of carbon nanotubes also has an important influence on the electrochemical performance of lead acid battery negative plates. After adding CNT, it can increase the amount of liquid absorption of the electrode, improve the transmission performance of the electrolyte in holes, and also improve the negative electrode conductivity, enhance the charging and discharging ability, improve the morphology and utilization rate of the active material, and slow down the salt of the negative electrode. In partial charge state, the rapid discharge cycle life of the plate can be extended. The negative electrode is added to the CNT battery prepared by 0.5 % CNT. When the SBAS0101 is rapidly charged and discharged under 50 % charge state, the battery discharge termination voltage is increased and the cycle life is extended.

Related Tags:Transparent Silver Colloid  Colloidal Gold

Conductive and antistatic nanomaterials commonly used in the textile and chemical fiber industry

The development of nanotechnology and nanomaterials provides new ways and ideas for the development of anti-static products. The special conductivity, electromagnetic properties, super-absorb ability and wide band of nanomaterials have created new conditions for the research and development of conductive absorbing fabrics. Due to the electrostatic effect, chemical fiber clothing and chemical fiber carpets have a discharge effect when rubbed, and at the same time, it is easy to adsorb dust, which brings a lot of inconvenience to the user; some operating platforms, cabin welding and other first-line work sites are prone to sparks due to static electricity, causing an explosion. . From the perspective of safety, it is an important task to improve the quality of chemical fiber products and solve the problem of static electricity.

If connected to the resin with nano-powders with semiconducting properties ( such as nano-TIO2, nano-ZNO and nano-FE2O3) , the resin will have electrostatic shielding performance, which greatly reduces the electrostatic effect and greatly improves the safety factor.

The anti-static master batch prepared by dispersing the multi-walled carbon nanotubes in the self-made anti-static carrier PR-86 can produce an anti-static PP fiber with excellent performance. The presence of multi-walled carbon nanotubes enhances the degree of polarization of the microfiber phase and the antistatic effect of the antistatic master batch. The antistatic properties of polypropylene fibers and the antistatic fibers made from polypropylene blends can also be improved by using carbon nanotubes.

The use of nanotechnology to develop conductive adhesives and conductive coatings, surface treatment of the fabric, or the addition of nano-metal powder during the spinning process to make the fibers conductive. For example, in the antistatic agent for polyester–Nano-doped tin dioxide (ATO) finishing agent, a reasonable stable dispersing agent is selected to make the particles mono-disperse, and the anti-static finishing agent is used to treat the polyester fabric, and the surface resistance of the fabric is The unprocessed >1012 Ω level is reduced to the order of <1010 Ω, washing 50 times, the antistatic effect is basically unchanged.

The conductive fibers with good performance include black conductive fibers with carbon black as conductive material and white conductive fibers with white powder materials such as nano SNO2, nano ZNO and nano TIO2 as conductive materials. The white-tone conductive fiber is mainly used for making protective clothing, overalls and decorative conductive materials. Its color is better than that of black conductive fibers, and its application range is wider.

Related Tags:Nano silver colloid  Silver nanoparticles dispersion

purple tungsten anode material

WO2.72’s purple finely divided crystalline powder, which is a purple tungsten oxide that can be used in negative electrode materials, which can help lithium-ion batteries achieve ultra-fast charging, so that high-power density battery devices can be constructed to achieve smaller and lighter Device.

Purple tungsten oxide has a very high chemical activity and enhances electron conductivity. The material has a small internal resistance and excellent Li ion diffusibility. In particular, it has excellent discharge characteristics in a low-temperature environment, and has a rate characteristic equal to or higher than that of a double-layer capacitor (EDLC) discharge even at -40 °C. Previously, the rate characteristics of Li ion secondary batteries and Li ion capacitors at low temperatures have been an unsolved problem.

A battery with a new material is characterized by a power density and an energy density that can be increased to two to three times that of a double layer capacitor. Energy density is also improved compared to lithium ion capacitors designed to increase the energy density of EDLC. In the field of capacitors, Li-ion secondary batteries are not suitable for high-output applications due to insufficient output power and development difficulties, and the development of such batteries will make it possible to use batteries in high-output power applications.

It is said that the new battery materials are very likely to be officially put into commercial use, which may further expand the demand for tungsten oxide. The application advantages of lithium batteries using new materials are quite obvious, ranging from automobiles, micro/mild hybrid trains, elevators, uninterruptible power supply UPS to high-current power supplies.

Related Tags:Colloidal Silver  Antibacterial nano silver dispersion

ATO nanopowder applied for anti-static fiber

Nano-inorganic powder modified fiber materials are gradually becoming an important development direction of fiber material modification. Compared with other types of anti-static fibers, nanoscale metal oxide anti-static fibers have many unique excellent properties, such as being unaffected by climate and use environment, and good stability; nanoscale metal oxides are not easy to get from fibers. Shedding, the distribution is relatively uniform; the fiber preparation process is simple; the fiber is used in a wide range, and it can be used in any occasion where anti-static is required. The new nano-scale transparent conductive powder is prepared for the transparency and excellent electrical conductivity of the product. It is favored by people. There are three main ways to use nano-ATO for anti-static treatment of chemical fiber:

 

1) Adding nano ATO powder directly during fiber spinning, the key is the compatibility of inorganic nano ATO with fiber material, and special dispersing aid needs to be added;

 

2) Adding nano ATO or its aqueous suspension during the dyeing process of raw materials (such as tops and polyester filaments) to complete the dyeing and functionalization in one step;

 

3) Adding a nano-sized ATO aqueous suspension to the dyeing or finishing process of the grey fabric.

 

Wang Dong and others of the State Key Laboratory of Fiber Modification of Donghua University used nano powder ATO powder as anti-static agent and polyethyleneimine (PEl) as dispersant to stably and uniformly disperse nano-ATO in deionized water. For the first time, the suspension was used as a preheating bath for the spinning process of polyacrylonitrile fibers to improve the anti-static property of PAN fibers. Due to the difference in concentration of nano-inorganic particles inside and outside the fiber and the presence of a large number of micropores inside the primary PAN fiber, the nano-ATO particles can diffuse, migrate into the fiber or adsorb to the surface layer of the fiber. When the PAN fiber is stretched, dried, and densified, The nano ATO can remain in the fiber and form a conductive channel for the partial contact of the nano ATO, imparting anti-static properties to the PAN fiber. The experimental results show that the volume resistivity of nano-ATO modified PAN fiber decreases by three orders of magnitude, has good anti-static properties, and basically maintains the original mechanical properties of the fiber. In addition, the National Ultrafine Powder Engineering Research Center is also conducting research on the application of nano-ATO in the preparation of anti-static fibers and other fields.

 

At present, the most important method to improve the electrostatic properties of polyester fabrics is to use an organic anti-static agent for anti-static finishing through a simple fabric finishing technique. However, since organic anti-static agents have a large dependence on environmental humidity and poor durability of anti-static effects, an anti-static agent having excellent and durable anti-static properties has been sought as a research and development hot spot. Wu Yue et al. Emi used nano ATO powder for anti-static treatment of polyester fabrics. The experimental results show that the surface resistance of polyester fabric treated with nano-ATO anti-static finishing agent is reduced from untreated >1012 Ω to <1010 Ω, washing 50 times. The anti-static effect is basically unchanged. Chen Xuexue et al. “The anti-static function of nano-scale ATO anti-static agent on polyester fabric was coated by coating method. The experimental results show that only when ATO particles are exposed on the surface of the film, it can exert anti-static performance; when ATO When the particles are partially immersed in the film and partially exposed in the form of the film surface, the anti-static property of the film is long. Ding Zhongfu et al. used nano-ATO powders with different cerium doping amount for the anti-static treatment of polyester knitted fabrics. Studies have shown that the doping amount of powder is one of the main factors affecting anti-static properties, and is doped at 4%-8% antimony. Within the range of the test, the more the doping amount, the better its anti-static property, but the color of the powder will also deepen, which will affect its use on light textiles.

 

Fiber functionalization is an important development trend of synthetic fibers. China is a large country in the production and consumption of chemical fiber. anti-static treatment of chemical fiber will be one of the important application markets for nano ATO powder.

Related Tags:Colloidal Silver  Antibacterial nano silver dispersion

Application of Nano Titanium Nitride in Electrochemistry

Nano titanium nitride can be dispersed in other materials to form a conductive network due to its small particle size and large specific surface area, which greatly improves the electrical conductivity of the composite. Therefore, nano titanium nitride is a material with broad application prospects. Among them, the application of nano titanium nitride TIN in electrochemistry is as follows:

1) Application in fuel cells

1 nano TiN as electrode catalyst carrier material

As a carrier material for the electrode of a fuel cell, nano titanium nitride TiN not only improves the electrooxidation ability of the anode to organic fuel such as methanol, but also improves the electroreduction catalytic performance of the cathode for oxygen, and synergistic effect with the platinum Pt. The corrosion resistance and long-term stability of the electrode are greatly enhanced, and the performance of the fuel cell is greatly improved.

Application of nano TiN in bipolar plate materials

The metal materials generally used as the plates include Ti, Al, and stainless steel, and the disadvantage of using the metal plates is that the corrosion resistance is relatively poor, which cannot meet the long-term stability of the fuel cell. TiN has high electrical conductivity, corrosion resistance, oxidation resistance and excellent mechanical properties. It is suitable for composite modification of metals such as Ti, Al and stainless steel to improve the corrosion resistance and electrical conductivity of bipolar plates.

2) Application in super-capacitors

Various nano structured TiN with excellent electronic conductivity and high specific surface area, such as nanotube arrays, nanowires, nanorods, and core-shell structures, can improve the capacitance performance and cycle stability of super-capacitors.

3) Application in lithium ion battery

As a carrier material for lithium-ion batteries, TiN not only improves the conductivity of the electrode, but also greatly increases the diffusion coefficient of lithium ions, thereby improving the capacity, rate and stability of the battery. It is widely displayed in lithium-ion batteries. Application prospects.

Silver nanowire “ink” makes paper-based printing electronic products possible

By suspending tiny metal nanoparticles in liquids, Duke scientists are developing conductive inks for inkjet printers that can print inexpensive, customizable circuit patterns on any surface virtually .

Printed electronics have been widely used on a number of devices, such as anti-theft radio frequency identification (RFID) tags that are usually found behind new DVDs. It currently has a major drawback: in order for the circuit to work, it must first be heated to fuse all of the nanoparticles into a single conductive filament, which makes it impossible to print circuits on cheap plastic or paper.

A new study by Duke University researchers shows that adjusting the shape of the nanoparticles in ink eliminates the need for heating.

By comparing the conductivity of thin films made from different shapes of silver nanostructures, the researchers found that electrons made of silver nanowires are much easier to fabricate than films made of other shapes such as nanospheres or microdisks. In fact, the flow of electrons through a film made of nanowires is so easy that they can be used in printed circuits without melting them together.

Benjamin Wiley, an assistant professor of chemistry at Duke University, said: “the conductivity of nanowires is 4000 times higher than that of commonly used silver nanoparticles that can be found on printed RFID tags. So if you use nanowires, then you don’t need to heat the printed circui to such a high temperature that you can use cheaper plastic or paper.”

Wiley added: “in addition to these silver nanowires, I really don’t think there is anything else that can be simply printed out like this. Without any post-processing, it can be directly conductive.”

Applications of these types of printed electronics may go far beyond smart packaging. Researchers envision using this technology to make solar cells, printed displays, LEDs, touch screens, amplifiers, batteries, and even some implanted bioelectronic devices.

Wiley said that silver has become a raw material for the manufacture of printed electronic materials, and many recent studies have shown the measurement of the electrical conductivity of silver nanostructure films of different shapes. However, experimental errors make it difficult to make direct comparisons between different shapes, and there are few reports that relate the conductivity of the film to the total mass of silver used, which is an important factor when using expensive materials.

“We want to eliminate any extra materials from ink, just focus on the silver content in the film and the link between the nanostructures as the only source of variation,” said Stewart, another graduate student.

Stewart uses known recipes to make silver nanostructures with different shapes, including nanoparticles, microchips, and short and long nanowires. These nanostructures are then mixed with distilled water to make a simple “ink.” He then invented a quick and easy way to make films using glass slides and double-sided adhesive tapes that can be easily found in any laboratory.

Stewart said: “We used punches to punch wells out of double-sided tape and stick it to the glass.” By adding a precise amount of ink to each well of the tape, the well was then heated to a temperature of The relatively low temperature at which the water evaporates or the relatively high temperature at which the structure begins to melt, he has obtained a variety of films for testing.

The research team said that they are not surprised that the long nanowire film has the highest conductivity. Electrons usually pass easily through a single nanostructure, but they tend to get stuck when they have to jump from one structure to the next, Wiley explained, while long nanowires greatly reduce the number of electronic “jumps.”

However, they were surprised by the intensity of this change. “The resistivity of long silver nanowire films is orders of magnitude lower than that of silver nanoparticles, and only ten times larger than pure silver,” Stewart said.

The team is now experimenting with aerosol inkjet printers to print silver nanowire inks in available circuits. Wiley said that they also want to explore whether silver-plated copper nanowires can produce the same effect, which is much cheaper than pure silver nanowires.