Preparation, optical properties and 1 × 2 polymeric thermo-optic switch of polyurethane-urea

► Preparation and structural characterization of a novel azo polyurethane-urea (PUU). ► The mechanical performance and thermal property of PUU film. ► The thermo-optic property, transmission loss and dispersion property of PUU. ► Proposed a new 1 × 2 polymeric thermo-optic switch.