Benefits of Aliphatic Diisocyanates (ADI) and their Derivatives in Thermoplastic Materials

摘要

Although aliphatic diisocyanates (ADI) account for only 3% of the world wide diisocyanate production capacity, these compounds and their derivatives are essential raw materials for polyurethane applications that require light and or color stability, e.g. coatings. In this presentation we will show that besides their traditional applications; ADI and their derivatives can also be beneficial as monomers or additives for thermoplastic elastomers. In the presentation we will discuss how the structure and selectivity of an aliphatic diisocyanate determines physical properties of the finished product including crystallinity, compatibility, glass transition temperature and viscosity. It will also help selecting which aliphatic diisocyanate will best suit a Specific application. Based on this knowledge, it can be concluded that H_(12)MDI is a very suitable aliphatic diisocyanate monomer for thermoplastic polyurethanes. It should be noted however that changing from MDI to H_(12)MDI will require raw material reformulation in order to reach the same mechanical properties of the original aromatic TPU. As an example for an application of an ADI derivative as an additive for thermoplastic materials, we will discuss the stabilization of polyesters by aliphatic polycarbodiimides.