The combination of aliphatic polyisocyanate and polyol allows formulators to achieve
high impact resistance required for demanding applications. Aliphatic polyisocyanates,
especially HDI derivatives bring an intrinsic elasticity due to their chemical structure
based on –(CH2)6– chain.
The choice of polyol also influences the elasticity of the final paint. The use
of polyester will be preferred when a very flexible coating is required.
Achieving a good balance between film hardness and flexibility is essential
to gain adequate impact resistance.