What is the difference between TPU film and PU film?

TPU (Thermoplastic Polyurethane) film and PU (Polyurethane) film are both types of polymer films, but they have some differences in their properties and applications:

Material Composition:

TPU Film: The main component of TPU film is polyurethane thermoplastic elastomer, which is a type of polyurethane plastic with excellent elasticity and durability. It is made by combining polyols and diisocyanates through a polymerization process.

PU Film: PU stands for Polyurethane, and it is the general term for a wide range of polyurethane materials, including both thermoplastic and thermosetting types. PU film typically refers to thermosetting polyurethane films, which are crosslinked and cured during the manufacturing process.

Elasticity and Flexibility:

TPU Film: TPU is known for its outstanding elasticity, flexibility, and resilience. It can be stretched repeatedly without losing its original shape and properties.

PU Film: While PU films can also exhibit some level of flexibility, they are generally less elastic than TPU films. Thermosetting PU films tend to have a harder and more rigid texture.

Manufacturing Process:

TPU Film: TPU films are produced using a melt extrusion process. The material is heated to a molten state and then extruded through a die to form a continuous film.

PU Film: Thermosetting PU films require a curing process during production. They are often made using a cast or calendering process, where the liquid PU is poured or rolled into a film and then cured through a chemical reaction or heat treatment.

Applications:

TPU Film: Due to its high elasticity and toughness, TPU film is commonly used in applications that require stretchability, such as sportswear, outdoor gear, elastic bands, and medical products like wound dressings.

PU Film: PU films find applications in various industries, including automotive (as coatings or protective layers), furniture (as synthetic leather), and packaging (as a barrier material). Thermosetting PU films are also used in certain specialized applications where resistance to abrasion, chemicals, and extreme conditions is required.

In summary:

The main difference between TPU film and PU film lies in their elasticity, manufacturing process, and specific applications. TPU is preferred when high elasticity and stretchability are needed, while PU films, particularly thermosetting types, are used in a broader range of applications where durability and resistance to various factors are crucial.