Synthesis and performance of transparent casting polyurethane resin

A series of transparent casting polyurethane resins (TCPU) were synthesized from cycloaliphatic diisocyanate (IPDI or H12MDI), polyol, chain extender, crosslinking agents, catalyst and special aids (T), which were characterized by FTIR. The thermal stabilities of the obtained TCPU were examined by DSC and TGA, the glass transition temperature (Tg) was in the range of 95–110°C, the initial decomposition temperature (5% weight loss) was 250–265°C, and 10% weight loss at the temperature was in the range of 260–286°C in nitrogen atmosphere. The morphologies of the fractured surfaces of TCPU were revealed by a scanning electron microscope (SEM). The crystalline-amorphous characters of TCPU were studied by WAXD, the result shows that TCPU possesses amorphous glassy characters. The optical properties of TCPU were studied by a UV-7500 visible light absorbance measurement. All the samples exhibited excellent optical properties and possessed light transmittance in the range of 91%–93%.