Nanotechnology Makes the Packaging World a New Look (3)

Nano-nylons increase the strength and heat resistance of nylon, reduce its water absorption, and have good barrier properties. Nano-nylons are easy to blow and extrude, and heat shrinkable casing films, biaxially stretched films, uniaxially stretched films, and composite films can also be prepared.

After 10 years of vigorous research and development, nylon nanocomposites eventually entered the practical stage of industrialization. US-based polyester manufacturer Eastman Chemicals and nanoclay supplier Nanocor Co., Ltd. jointly developed nano-nylon under the trademark Imperm, which is used as a barrier core material for PET/nylon/PET three-layer bottles. The nano-nylon is made by adding nano-clay to the amorphous nylon MXD6 based resin of Mitsubishi Gas Chemical Corporation in Japan, so the barrier property is greatly improved, and the oxygen permeability is 100 times smaller than that of ordinary PET. This product is currently used in 16 ounce non-sterile beer bottles. Imperm nano nylon core layer thickness only accounts for 10% of the total thickness of the bottle layer, and there is no need for an adhesive layer between the two layers of PET, which has almost no effect on the transparency of the bottle. It is said that the shelf life of beer can be increased to 28.5 weeks.

In addition to the huge market for beer bottles, nano-nylon can also be used as a film packaging material for foods such as meat and cheese products. In addition, Germany's Bayer Corporation uses nano-nylon as a cast film for multilayer packaging materials for the preparation of medical products and protective films for corrosive articles.

The Institute of Chemistry of the Chinese Academy of Sciences used montmorillonite layered silicates as inorganic dispersions to develop high-performance nanometer nylon 6 membranes. It is suitable for blow molding and extrusion to prepare a variety of plastic packaging films, compared with ordinary films. Nano-Nylon 6 film has better barrier properties, mechanical properties and transparency.

Peter Maul, president of Nanocor, a nanoclay manufacturer in the United States, believes that 2003 was a year when nanocomposites really entered the industrialization stage. The strategic cooperation contract signed in 2003 between PolyOne (PolyOne) and Nanocor, a large-scale compounding resin production and distribution company, is of great significance. Maul referred to this cooperation as the close cooperation between the two companies in the industrialization of polyolefin-based nanocomposites and the sales of their products. Nanocor sold nanoclay (montmorillonite) named Nanomer to PolyOne, and in June 2003, PolyOne launched the Nanoblend masterbatch, Nanometer's industrial nanocomposite additive product series. The content of up to 40%, to replace the traditional inorganic filler, glass fiber reinforced materials and flame retardants, added to the polyolefin resin.

Nanocor also has a special contract with plastic compounders Gitto Global and Nobel Polymer LLC to supply nanoclay Nanomer. Gitto Global has begun to introduce fully industrialized nanocomposite grades and flame-retardant plastic compounds to the market. Nobel Polymers recently announced the launch of PP nanocomposites, replacing glass-reinforced PPs, to produce automotive seating, furniture and appliance components. Another strategic partnership of Nanocor is to jointly develop high-barrier nylon nanocomposites and their applications with Mitsubishi Gas Corporation of Japan. Imperm has industrialized the use of films and bottles as barrier materials. At present, Imperm is only produced in Japan, and it is now starting to build the Imperm production facility in the United States. It plans to start production in early 2005.

Nano antibacterial agent

MOD series nano high-performance inorganic antibacterial agent is a new type of inorganic antibacterial packaging material that introduces nano technology into aseptic composite packaging. It uses MOD active gene and inorganic nano silver compound as main antibacterial component, and uses various inorganic materials as carrier. Inorganic antibacterial powder. The antibacterial material is prepared by using high-tech nanotechnology, which changes the traditional antibacterial agent production process using simple metal ions such as silver, copper, and zinc as antibacterial active ingredients. The antibacterial mechanism is metal ion action and photocatalysis, with strong long-lasting antibacterial function, antibacterial rate up to 99.9%, completely solve the problem of discoloration of inorganic antibacterial packaging materials in the application, is a non-toxic broad-spectrum antibacterial agent, Can be widely used in the production of liquid milk, beverage aseptic composite packaging products.

Nano-inorganic antibacterial agents fall into two categories. One type is metal nano oxides with antibacterial activity, represented by TiO2 and ZnO. They generate active oxygen in water and air under ultraviolet radiation, have strong chemical activity, and can react with various organic substances. As a result, most germs and viruses are killed. Therefore, it can be used to produce antibacterial fibers, antibacterial plastics, antibacterial glass, antibacterial ceramics, antibacterial building materials, and the like. Experiments have shown that coating a thin layer of TiO2 on the glass and light for 3 hours can achieve the effect of killing the coliform. After 4 hours of light exposure, the toxin can be controlled below 5%. The other type is a compound antibacterial body mainly composed of silver and zinc. With fine TiO2 and SiO2 as carriers, due to the special effects of ultra-fine nano-sized particles, the overall antibacterial effect is greatly improved, and the moisture resistance and powder are greatly improved. The fineness, dispersion, and functional effects have all been brought into full play. For example, nano-composite silver antibacterial powder MFS350 developed by Zhoushan Mingri Nanomaterials Co., Ltd. uses nano-SiO2 as the main raw material, and its average particle size is less than 90 nm, which is characterized by high efficiency, rapidity, long-lasting, and broad antibacterial spectrum.

The MOD nano high-performance inorganic antibacterial agent developed by Zhejiang Lishui Golden Asia Nanomaterials Co., Ltd. is a new type of inorganic antibacterial agent developed by combining photocatalytic antibacterial technology, metal ion antibacterial technology and nano preparation technology. And to stop the growth of bacteria and prevent the growth of various microorganisms, it also has the durability and safety of antibacterial action. Applying MOD to various materials can make many related products.

Japan adds a new type of inorganic antibacterial agent to the packaging material, and it is currently widely used as an antibacterial film. Pure natural base materials can exert amazing bactericidal effect under the transformation of nanotechnology. Antibacterial and aseptic packaging can denature or sediment the bacteria. Once it encounters water, it will exert greater destruction on the bacteria. The adsorption capacity and penetrating power are also very strong, and it also has a strong antibacterial effect after multiple washings. The antifouling film has an efficiency of more than 98% in the barrier aerosol, and the film has excellent air permeability, barrier, and filtration properties.

Nano coating

Nano coatings have varying optical properties, and their optical transmission spectrum extends from the ultraviolet to the far infrared. Nano-multi-layer composite coatings can exhibit fluorescence in the visible light range after being processed, and nano-material coatings are applied on the surface of various signs to become reflective signs. Changing the composition and properties of nano-coatings can produce photochromic, thermochromic, electrochromic and other effects, and is a special anti-counterfeiting and identification method.

Adding functional nanomaterials in traditional coatings can greatly improve the performance of coatings. Such as the nano-calcium carbonate added to the ink instead of barium hydroxide, barium sulfate, aluminum barium and other traditional ink filler (plasma pigment), can be made of good stability, high gloss, good drying performance, adaptability of nano-modified Ink. After adding a small amount of nano-SiO2 to traditional coatings (especially exterior paints), the anti-ultraviolet aging performance of the product has been increased from the original 250 hours to more than 600 hours; the scrub resistance has been improved from 1000 times to more than 10,000 times, and the drying time has been greatly reduced. The problem of poor suspension stability, poor thixotropy, and low finish is also greatly improved.