Polyurethane film is more and more widely used

With the increasingly widespread application of polymer films, the performance requirements for film materials are getting higher and higher. Commonly used polysulfone and polyolefin films cannot fully meet market demands. In this case, polyurethane films have emerged. At present, the development and application of polyurethane films in foreign countries is in the ascendant, and domestic research and application are starting to take off.

Polyurethane films are mainly prepared by processes such as extrusion, calendering and blow molding. Due to the characteristics of the molecular structure of polyurethanes, one can change the elasticity, hardness, and hydrophilicity of polyurethane block components by adjusting their proportions. Therefore, the polyurethane film has the same excellent high tension, high tensile force, waterproof breathability, toughness, and aging resistance as the polyurethane elastomer, and at the same time, it has excellent biological and blood compatibility and chemical resistance. Widely used in medical and health, high-grade textile fabrics, industrial and other fields, deeply welcomed by users.

In the medical and health field, thermoplastic polyurethane films are used, such as surgical gowns, medical gloves, medical mattresses, ice packs, bandages, blood bags, condoms, wound dressings, and artificial organs. Waterproof and breathable polyurethane medical gloves provide excellent water vapor permeability, bacteria resistance and comfort. Traditional wound dressings have many drawbacks, and the use of polyurethane microporous and hydrophilic membranes can make the wound dressings have good air permeability and absorption function. The good biocompatibility of polyurethanes can also be used as transdermal delivery dressings, which can effectively sequester drugs The unnecessary diffusion of the active ingredient can ensure that the active ingredient acts on the skin at a certain penetration rate. Currently, it has been widely used in foreign countries. The domestic Sichuan University Biomedical Engineering Center has also successfully developed a new type of polyurethane double-layer wound dressing with good results.

Polyurethane film is used as a medical apparel fabric, which has the advantages of breathability, anti-bacterial, anti-fluid permeation, long-term washing and steam sterilization, no degradation and reasonable price. In recent years, thermoformed polyurethane films developed abroad are used to produce a low-diameter balloon with a general aspect ratio that cannot be produced by other film materials and are used in urinary systems, cardiovascular systems, and tumor treatment devices. In addition, the application of polyurethane film on man-made tubes such as artificial heart and artificial anal bags also showed good development potential.

The same as the polyurethane film has optical transparency, soft feel, high stretchability, durability, easy processing and waterproof breathable, as a high-end or special textile fabrics are widely used in daily life. The earliest polyurethane films and coatings were first applied to the clothing of outdoor workers engaged in agriculture, construction, forestry, mountaineering and marine and air rescue, and later expanded to footwear. At present, polyurethane film is widely used in footwear, such as various kinds of footwear, which are sports or special functions of footwear fabrics and inner materials; in recent years, polyurethane films are increasingly used in the preparation of clothing and fashion, using breathable The garments made of polyurethane film materials not only have respiratory function but also can be antistatic; polyurethane films are used in sportswear and products to produce wetsuits, swimwear, rhythm suits and air landing suits, inflatable waterbeds, ball bladders, and pelts. Boats, lifebuoys and other materials and materials. The newly developed shape-memory polyurethane film has good crystallinity. Blocks are aggregated into micro-zones to act as physical cross-links. Shapes of shape-memory polyurethanes are controlled and restored. The shape memory temperature of these shape-memory polyurethanes is set at room temperature. For the production of composite fabrics, as home clothing fabrics, can play a warm role below room temperature, can have good moisture permeability above room temperature.

In the industrial field, polyurethane films are often used for fire protection, heat insulation, sound insulation materials, aircraft parts and decoration, automotive parts, waterproof stickers, compression seals, drive belts, insulation panels, and security bulletproof glass. Such as the United States to make it into car film products for the hood front edge, the front and rear bumpers, door panels, door lock handle and other cladding, to avoid stone hit, wear and protect the car finish and other occasions The polyurethane film has good optical transparency and light stability; many automobile manufacturers in China also use imported polyurethane film to package and protect the interior and exterior of automobiles. The British developed a bullet-proof glass for use in aircraft and bulletproof sedans that is bonded with a multilayer polyurethane film. When the polyurethane-based plastic film is used in the field of mold industry, metal and weapon anti-corrosion, etc. .

With the advancement of science and technology, the performance of polyurethane films is also increasing from Zhejiang to Zhejiang. For example, Toray Corporation of Japan has developed a process that can significantly improve the heat resistance and strength of polyurethane films, and it mainly adopts nanotechnology that can control the structure of materials at molecular level. . Blend modification has also played an increasingly important role in the modification and application of polyurethane films, such as the domestic development of silk / polyurethane blend film, polyurethane / polyoxyethylene sulfonate sodium composite film. In addition, there are also a large number of research reports on reducing the production cost of polyurethane films and improving the preparation process.

Polyurethane film in the United States and Japan in Western Europe have been greatly developed, especially in the military, high-end and specialized clothing and medical fields. However, the research and application of polyurethane film in China is still in its infancy. Most polyurethane films and coatings rely on imports, and are processed into medical materials and textiles and then exported to foreign countries. At present, China is only able to produce some common low-performance polyurethane film materials, which is very weak in production and application research. In particular, the research and production of functionalized polyurethane films is far from the foreign countries. With the continuous development of China's economy, domestic medical The requirements for the number and functionalization of polyurethane films in hygiene, clothing and other fields will increase rapidly, and therefore the application market for polyurethane films in China will have a huge impact.