what is tpu?
A TPU is a multi-phase block copolymer that is created when three basic raw materials are com-bined together in a specificway. The individual components required to produce a TPU are:â¢ A polyol or long-chain diolâ¢ A chain extender or short-chain diolâ¢ A diisocyanate Figure 1.0 depicts the basic chemistry of TPU. The soft block, built out of a polyol and an isocyanate, is responsible for the flexibilityand elastomeric character of a TPU. The hard block, constructed from a chain extender and isocyanate, gives a TPU its toughness and physical performance properties. 6 2. TPU chemistry Figure 2.0 highlights the cross-linking structure of a thermoplastic elastomer versus a thermoset rubber.