Extruded PP (Polypropylene) Rod

The PP (polypropylene) rod is a semi-crystalline material that stands out due to its unique combination of physical and mechanical properties. One of its most notable characteristics is its hardness and high melting point, which sets it apart from other materials like PE (polyethylene). While the homopolymer type of PP can become quite brittle when exposed to temperatures higher than 0°C, many commercial PP materials are formulated as random copolymers or clamp copolymers with varying percentages of ethylene.

Random copolymers typically contain 1 to 4% ethylene, while clamp copolymers have a higher ratio of ethylene. This copolymerization process results in a PP material with a lower heat distortion temperature (100°C) compared to homopolymer PP. Although the copolymer type PP material may have lower transparency, gloss, and rigidity, it exhibits a stronger impact strength. As the ethylene content in the copolymer increases, the overall strength of the PP material also increases, making it a versatile option for various applications.

Another important characteristic of PP is its Vicat softening temperature, which is 150°C. This high temperature resistance, combined with the material's high degree of crystallinity, results in excellent surface stiffness and scratch resistance. These properties make PP an ideal choice for applications where durability and resistance to wear and tear are crucial.

Furthermore, PP is known for its resistance to environmental stress cracking, which is a common issue in many other materials. This makes it a reliable choice for use in environments where exposure to chemicals, moisture, or other stressors is likely.

In addition to its mechanical properties, PP also offers excellent processability. It can be easily shaped and formed using a variety of manufacturing processes, such as injection molding, extrusion, and blow molding. This versatility, combined with its other properties, makes PP a popular choice for a wide range of applications, including packaging, automotive parts, and consumer products.