Preparation and Characterization of Collagen/TiO_2 Nanocomposite with Low Infrared Emissivity

New organic-inorganic nanocomposite materials of collagen and modified TiO2 were prepared. The change of content of collagen in the nanocomposites along with the alteration of temperature and pH value was studied, and the influence of such factors as types of TiO2 crystals, Al2O3 films of modification on TiO2 and cross-link with glutaraldehyde on the infrared emissivity of the composites was investigated. The results indicate that the optimal temperature and pH value for the reaction between collagen and modified nanosized TiO2 are 50℃and 8.0 respectively, under which the content of collagen increases up to 9.45wt%. The nanocomposites are endowed with much lower infrared emissivity and the thermal stability of the nanocomposite materials is enhanced greatly due to the strong interactions between collagen and modified nanosized TiO2. After being cross-linked by glutaraldehyde, disorderly distributional nanocomposites are turned to regular and ordered laminar netty ones, which improves the tensility and stability of the materials and lowers the infrared emissivity further to 0.502.