Polypropylene, also known as PP plastic, is one of the most important thermoplastics. Being a thermoplastic means that it can be molded when heated and retains its shape when cooled. Polypropylene’s significance as one of the most widely used plastic types is attributed to its high durability, toughness, excellent coverage, non-absorbent properties, resistance to bacterial attacks, and the ability to be cleaned even at low temperatures. Additionally, polypropylene has the lowest density of any fiber, which also means it can float.
Properties of Polypropylene
As a starting point, polypropylene is a whitish and opaque material due to the high crystallinity of PP plastic. However, it is possible to color polypropylene in virtually any color. Polypropylene exhibits high resistance to heat and can withstand temperatures of up to 120°C without losing its shape stability. This allows for the sterilization of products made of PP plastic by boiling them. The ability to sterilize products also facilitates their recycling. The melting point of polypropylene is 165°C, and it can be processed through methods such as injection molding, extrusion, blow molding, thermoforming, and rotational molding. PP plastic has very low surface tension, making it difficult to bond or print on. To achieve consistent adhesion or printing, the surface needs to be treated beforehand.
Uses of Polypropylene
Polypropylene is used in a wide range of products, primarily due to its high durability, toughness, excellent electrical insulation properties, and resistance to liquids and chemicals. The ability to sterilize products by boiling also contributes to the extensive use of PP plastic in the development of various products.
Polypropylene is used for food packaging, furniture, plastic bags, sports equipment, and clothing. In the case of clothing, PP plastic is particularly used for the production of moisture-wicking garments because it does not absorb moisture in its core but has the ability to transport moisture through the fibers, moving it away from the body. Polypropylene is also widely used in the automotive industry, such as in the production of dashboards, bumpers, and other car components, due to its strength, resistance to liquids and chemicals, and heat resistance.
Furthermore, polypropylene can be used for pipes, filters, pipettes, inhalers, and cable insulation, mainly because of its excellent electrical insulation properties.
Polypropylene in the Food Industry
In the case of plastic bags and clear packaging for food products, polypropylene is copolymerized with 2-5% ethylene to enhance product transparency. The use of polypropylene for products that come into contact with food is possible because it is FDA-approved for use in the food industry. Copolymerization also allows these products to withstand freezing temperatures, making it possible to freeze items like ready-made meals, fish, meat, and more in such packaging. Additionally, copolymerization results in products with much higher impact strength at low temperatures.
What is PP plastic?
Polypropylene, also known as PP plastic, is among the most important thermoplastic materials. Being a thermoplastic means that it can be shaped when heated and retains its form when cooled. The fact that polypropylene is one of the most significant and widely used types of plastic is due in part to its high abrasion resistance and toughness, its excellent coverage, its non-absorbent nature, its resistance to bacterial attacks, and its ability to be cleaned, even at low temperatures.
