[Chemical Knowledge]：Properties, uses, upstream and downstream raw materials, storage methods, properties of polypropylene

PROPERTIES OF POLYPROPYLENE

Polypropylene (Polypropylene, PP) is a thermoplastic polymer that is polymerized from propylene monomer. Its physical properties include high transparency, high toughness and good impact resistance. The melting point of polypropylene is higher, generally between 160-170 degrees Celsius, so that it exhibits better thermal stability under high temperature conditions. It has a density of about 0.90-0.91g/cm³ and is a lightweight material. Chemically, polypropylene has excellent chemical resistance and good resistance to most acids, alkalis and organic solvents.

Use of polypropylene

Due to its superior physical and chemical properties, polypropylene is widely used in many fields. In the packaging industry, polypropylene is used as food packaging materials, such as transparent food containers and plastic wrap, because of its non-toxic and good moisture resistance. In the medical industry, polypropylene is used to manufacture parts for disposable syringes, vials and medical devices, taking advantage of its high transparency and good hygiene properties. Polypropylene is also used in the automobile manufacturing industry, used to make automotive interior parts, battery shells, etc., because of its light weight, durability and easy to form. Polypropylene is also widely used in the construction industry, such as the manufacture of pipes, flooring and insulation materials.

Polypropylene Upstream Raw Material

The main upstream feedstock for the production of polypropylene is propylene (Propylene). Propylene is an important petrochemical product, which is mainly extracted from petroleum by petroleum cracking or catalytic cracking processes. Another method for obtaining propylene is through the dehydropropane (PDH) technology, which has received attention in recent years due to its high economic efficiency. In addition to propylene, the production process requires the use of catalysts, such as Ziegler-Natta catalysts or metallocene catalysts, which play a key role in the polymerization reaction and determine the molecular weight distribution and stereoregularity of the polymer.

Polypropylene downstream products

Polypropylene is processed into a variety of downstream products, widely used in various industries. Packaging materials are the most important downstream products, including various films, containers and bags. Secondly, fiber products, such as carpets, ropes and non-woven fabrics, occupy an important position in the textile industry. Injection molding products are also important downstream products of polypropylene, covering household appliances, toys, auto parts, etc. Polypropylene is also used in the production of pipes and plates, widely used in construction and agriculture.

Polypropylene production process

The production of polypropylene mainly uses three processes: bulk polymerization, solution polymerization and gas phase polymerization. The bulk polymerization method is to polymerize propylene in a liquid state, no solvent is required in the production process, and the product purity is high, but the requirement for reaction equipment is high. The solution polymerization method is to carry out polymerization in the presence of a solvent, and the reaction temperature and pressure are relatively low, but a subsequent solvent recovery and separation process is required. Gas phase polymerization is the polymerization of propylene gas under the action of catalyst, which has the advantages of simple operation and low production cost, and has become the most widely used polypropylene production process.

POLYPROPYLENE STORAGE METHOD

Polypropylene needs to pay attention to moisture-proof, heat-proof, fire-proof and other issues during storage. Polypropylene should be stored in a dry and ventilated warehouse to avoid moisture and prevent physical performance degradation. Direct sunlight and high temperature environment should be avoided to prevent polypropylene from aging and deterioration. Since polypropylene is a flammable material, fireworks should be prohibited in the warehouse and equipped with corresponding fire fighting facilities. Storage should avoid contact with strong acids, strong bases and organic solvents, so as to avoid chemical reactions, affecting the quality of polypropylene.

Polypropylene Market Analysis

The global PVC market has maintained steady growth in recent years, mainly driven by demand growth in downstream industries such as packaging, automobiles and construction. The Asia-Pacific region is the largest consumer market for polypropylene ethylene, especially in China and India. The acceleration of industrialization and urbanization has promoted the growth of demand for polypropylene ethylene. The increasingly stringent environmental regulations have prompted companies to continue to develop and produce environmentally friendly polypropylene products, such as degradable plastics and bio-based plastics, which is also an important direction for future market development.

POLYPROPYLENE FUTURE DEVELOPMENT TREND

In the future, the development of polypropylene will show several major trends. With the enhancement of environmental awareness and strict regulations, low-carbon environmentally friendly PVC products will become the mainstream of the market. Technological innovation will continue to promote the progress of polypropylene production process, improve production efficiency and reduce costs. Furthermore, the application of polypropylene in the field of high-performance materials will be further expanded, such as high-demand applications in the fields of electronic appliances, aerospace and so on. With the development of recyclable economy, the recycling and reuse technology of polypropylene will get more attention and investment, and promote the efficient use of resources and environmental protection.

Conclusion

As an important thermoplastic polymer, polypropylene has excellent physical and chemical properties, and is widely used in packaging, medical, automotive, construction and other fields. Its production involves upstream raw materials such as propylene and is produced by processes such as bulk polymerization, solution polymerization and gas phase polymerization. The reasonable storage method and the development trend of the future market show the important position and broad prospects of polypropylene ethylene in modern industry. In the future, with the advancement of technology and the improvement of environmental protection requirements, polypropylene will continue to play an important role in various fields.