Characteristics of the most popular polypropylene

According to insiders, the production of cast film is on the rise in the world packaging material market, and the cast film industry is entering a new era, that is, a round of investment boom on the basis of different fixtures. The production of cast film in China started in the 1980s. With the continuous development and expansion in the past 20 years, it has become a sunrise industry with considerable production capacity and production level in the packaging industry

polypropylene cast film (CPP) is a non stretched, non oriented flat extruded film produced by melt casting quenching. Compared with film blowing, it is characterized by fast production speed, high output, good film transparency, gloss and thickness uniformity, and excellent performance balance in the field of lithium batteries with anisotropic layout. At the same time, because it is flat extruded film, the subsequent processes such as printing and compounding are very convenient, so it is widely used in the packaging of textiles, flowers, food and daily necessities

cpp can be produced by single-layer casting and multi-layer coextrusion casting. The single-layer film mainly requires good low-temperature heat sealing performance and flexibility of the material. The multi-layer coextrusion casting film can generally be divided into three layers: heat sealing layer, supporting layer and corona layer. The selection of materials is wider than that of single-layer film. Materials that meet the requirements of each layer can be selected separately to endow the film with different functions and uses. Among them, the heat sealing layer group should be heat sealed, which requires that the melting point of the material is low, the hot melt is good, the heat sealing temperature should be wide, and the sealing should be easy; The supporting layer supports the film and increases the stiffness of the film; The Institute is expected to complete the halo layer in early 2015, and the halo layer will be printed or metallized, requiring moderate surface tension and strict restrictions on the addition of additives

with the increasing market demand, the products and materials of casting film are also being updated day by day. CPP's new product development mainly focuses on ultra-low temperature heat sealing film, cold resistant film, high temperature cooking film, etc. Some special-purpose films are also being developed and applied, such as antistatic films, pesticide films, highly transparent and ultra flexible films, which are gradually being introduced to the market and occupy new application fields

with the development of CPP production scale and extrusion equipment, the use of raw materials and the range of optional cold light lamps in the main working areas are increasing, which makes polypropylene special materials for casting develop in the direction of more refinement, specialization and higher performance. Various special materials with more refined division of labor continue to emerge. Each material plays its own role at different levels, endowing the film with new properties to meet different market needs. At the same time, the special production of high-performance raw materials for the special requirements of users is also emerging, which will bring greater profits to resin producers. At present, the development hotspot of special materials is low-temperature heat sealing materials. The industrialized butene/propylene random copolymer is a newly launched product in the market. Compared with the conventional B/C random copolymer, when the heat sealing temperature is the same as 100 ~ 112 ℃, the heat sealing strength of this product is much higher, and there is less frost and fog

in recent years, with the strengthening of the consumer market, the application field of CPP has been expanding, and its development has been accelerated. So far, there are more than 30 CPP manufacturers, more than 40 production lines, and a total production capacity of about 150000 ~ 170000 tons/year. However, the dependence of special materials for cast film on imported materials is more serious than BOPP film and blown film. At present, the annual import volume accounts for about 60% of the total consumption. Domestic CPP special materials are relatively single, only produced by Shanghai Petrochemical Co., Ltd. and Beijing Yanshan Petrochemical Company. They are generally used for composite film heat sealing layer, and resins for semi cooking film and aluminized film high-temperature cooking film are relatively scarce. At the same time, the product similarity of domestic enterprises is more serious. The equipment production capacity of similar low and medium-sized products increases more than the demand increases, and the market is relatively weak, which inhibits the expansion of film production and the rise of prices. In addition, in the past two years, the multi-layer coextrusion blown film market is in the growth stage, and some varieties of CPP films are subject to competition and impact

now, CPP has become an indispensable product in the packaging industry. Manufacturers use new equipment and materials to constantly expand production scale, improve production efficiency, increase product types, and expand new application fields. It can be expected that with the improvement of China's economic level and consumption level, its production development will be further expanded. At the same time, it should also be noted that the cast film is still partially or completely dependent on imports. How to speed up its localization is also a major problem that needs to be solved as soon as possible in the plastic processing and resin production industries

source: CHEMCHINA