Current situation of multi-layer coextrusion techn

Current situation of multi-layer coextrusion technology in China

in recent years, multi-layer coextrusion technology has been welcomed by China's flexible packaging production enterprises. Multi layer coextrusion machinery has not only achieved results in material, functional feeding combination, formula research, die design and manufacturing, but also made some progress in promoting the innovation of coextrusion composite film-forming technology. With the multi-layer coextrusion composite film becoming a new favorite in the packaging market, it is widely used in car bumpers, ventilation ducts, helmets, kitchen appliances, Lego building blocks and many other products, and the production equipment of this product has also become a hot spot of market development

multi layer coextrusion technology directly uses more than one kind of plastic particle (or plastic powder) as raw material, melts and plasticizes each kind of plastic respectively through more than one extruder, and then supplies it to a pair of die (or through the distributor, merges the plastics supplied by each extruder and supplies it to the inlet die), and then after further processing, the multi-layer composite film is prepared. Multi layer coextrusion technology is different from dry compounding and other compounding technologies. It does not need to make plastic particles into thin-film intermediate products first. Multi layer coextrusion technology represents the direction of economy and environmental protection

according to the survey, multi-layer coextrusion technology is widely used in China's flexible packaging production enterprises, and the application rate has reached 76.9%. At present, multi-layer coextrusion technology mostly adopts heterogeneous plastic coextrusion composite. Due to the great difference in properties between polar polymer compounds and non-polar polymer compounds, the properties can complement each other. Through the complementarity between the properties of each layer of materials, high-performance composite films can be prepared. Therefore, multi-layer coextrusion technology is often used in the production of high barrier composite films. China introduced single-layer film blowing machines from Italy in the mid-1980s, three-layer coextrusion film blowing equipment from bamag, Germany in the early 1990s, and the world's most advanced five layer, seven layer, nine layer or even twelve layer multi-layer coextrusion equipment in the middle and late 1990s. The development speed is faster and faster

on the basis of introducing foreign equipment, Chinese enterprises carry out digestion, absorption and technical cooperation, and further develop and innovate. At that time, balcony panels do not need to be covered with large areas of extruded plates up to 3 cm thick. Gradually, Chinese enterprises can design and manufacture better domestic machinery by themselves, but there is a big gap compared with the international advanced level. In the survey of flexible packaging factories, it is found that 16% of flexible packaging enterprises have the same level of application of this technology as foreign countries, while 42% of enterprises have a poor level of application of this technology, lagging behind foreign countries for more than 10 years. It is believed that with the vigorous development of multi-layer coextrusion equipment and related processes, the development of multi-layer coextrusion plastic composite film in China will have a broader prospect

source: China plastic manufacturing