Thermal Properties of Polyurethane Films Prepared from Mixed Cellulose, Hemicelluloses and Lignin

Polyurethane (PU) films were prepared from liquefied cellulose, hemicelluloses and lignin in different proportions. The simplex-lattice design method was employed to investigate the effects of each component and their associated interactive effects on the properties of the liquefied products and the PU films. Thermal properties were studied by means of Dynamic Mechanical Analyzer (DMA) and Thermal Gravimetry Analyzer (TGA). Results showed that the contents of cellulose, hemicelluloses and lignin significantly affected the thermal properties of PU films. The results of DMA suggested that the addition of the liquefied materials increased the glass transition temperature (T-g) of polyurethane (PU) films but decreased both storage modulus (E') and loss modulus (E ''). TGA results indicated that the addition of the liquefied materials decreased the thermal stabilities of the PU films