TPU

Thermoplastic polyurethane (TPU) is a segmented block copolymer consisting of alternating soft and hard segments. The soft segments (SSs) are composed of long-chain diols (most typically polyester, polyether, or polycaprolactone-based) with a molecular weight of 1000–4000 g/mol, while the hard segments (HSs) typically consist of alternating diisocyanates and short-chain extender sequences ^[1]. The Alliance for the Polyurethane Industry (API) describes TPU as "bridging the gap between rubber and plastics", since TPU has properties ranging from high performance elastomers to tough thermoplastics. These properties include but are not limited to modulable flexibility, elasticity, good wear resistance and transparency.

Figure 1: The alternating structure of TPU. HS: Hard segment; SS: Soft Segment ^[2].

As a leading global supplier, you can rely on Alfa Chemistry for all your TPU needs. We are committed to providing you with different specifications of TPU to meet your scientific or industrial applications. Contact us today to discuss your specific needs.

Performance Characteristics

TPU has a variety of performance characteristics, so it is suitable for all walks of life. Its main performance characteristics are as follows:

• Flexibility and Elasticity: TPU provides high flexibility and elasticity, and can withstand repeated bending and stretching without losing its original shape.
• Durability and Tear Resistance: TPU has excellent tear resistance and tensile strength, making it a popular durable material.
• Chemical and Weather Resistance: TPU shows excellent resistance to oils, greases, and certain chemicals, as well as resistance to weathering, UV rays, and moisture.

Factors affecting TPU performance

The final performance of TPU is influenced by several factors, each of which plays a vital role in the performance of materials in specific applications. The main influencing factors include but are not limited to: the polymerization procedure employed during the synthesis, the processing method and thermal history of the polymer, the chemical structure of the monomer used, the solubility parameter, the molecular weight, the glass temperature of the polyol, the volume fraction of the HSs and SSs in the copolymer, the intermolecular interaction between HSs-SSs, the characteristics of raw materials such as polyols, diisocyanates, and chain extenders ^[3].

Considering the above factors, manufacturers and engineers can optimize TPU formulations for different applications to ensure that the final TPU product has the desired performance characteristics.

Applications

TPU has applications in textiles and apparel, medical, electronics, automotive, membrane and filtration, and environmental protection. Its specific applications are described below.

• Textiles and Apparel: TPU films are waterproof and breathable and can be used in sportswear, rainwear and footwear.
• Medical: TPU is biocompatible and elastic for medical applications such as wound dressings, medical gowns and inflatable medical devices.
• Electronics: TPU films have electrical insulation and mechanical properties that protect electronic displays and components.
• Automotive: TPU is employed in interior and exterior automotive components, including airbags, upholstery, and protective covers.
• Membrane and Filtration: TPU offers excellent breathability and chemical resistance for use in breathable membranes, air filters and liquid filtration.
• Environmental Protection: Biodegradable TPU is being developed as a sustainable alternative to traditional TPU, contributing to reduced environmental impact.

Our Products

Alfa Chemistry provides customers with TPU in different material forms. The specific products are as follows:

TPU Films

TPU Granules & Powders

References

1. Martin, D. J.; et al. Thermoplastic polyurethane (TPU)-based polymer nanocomposites. Advances in Polymer Nanocomposites. 2012, 321-350.
2. Qi, H. J.; Boyce, M. C. Stress–strain behavior of thermoplastic polyurethanes. Mechanics of materials. 2005, 37(8): 817-839.
3. Datta, J.; Kasprzyk, P. Thermoplastic polyurethanes derived from petrochemical or renewable resources: A comprehensive review. Polymer Engineering & Science. 2018, 58(S1): E14-E35.