Synthesis of TPU/TiO2 nanocomposites by molten blending method

Efficient flame-retardant TPU/TiO2 nanocomposites were synthesized by molten blending method. The morphological and structural analysis indicated that TiO2 nanoparticles could be well dispersed in TPU and increased compatibility with the polymer. The obtained mechanical and thermal data suggested that intense cross-linking interaction between TiO2 and TPU promoted more stable network structure, which increased tensile length at break, storage modulus and loss modulus and thermal stability. Furthermore, the cone results demonstrated that TiO2 could not only decrease HRR, but also provide more stable char due to its high heat resistance, and catching and isolating oxygen molecules. Though ignition was inevitably earlier and peak value appearance caused transient thermal conductivity, TiO2 could greatly deplete combustible smoke particulates on the surface of TPU by accelerating degradation of combustible gases to prevent further penetration and destruction from TPU surface as oxygen insulation barrier. Therefore, TiO2 as a kind of effective flame-retardant and smoke suppression material can be applied in the flame retardancy of TPU.