Functional nano SiO2/polypropylene carbonate composite material and preparation method therefor

The invention relates to a functional nano SiO2/polypropylene carbonate composite material and a preparation method therefor. In the composite material, a mas ratio of the polypropylene carbonate to the functional nano SiO2 is 100 to (0.5-6); and the composite material is prepared by fusing and blending the polypropylene carbonate and the functional nano SiO2. The functional nano SiO2 is prepared by virtue of an in-situ modifying technology. The functional nano SiO2/polypropylene carbonate composite material provided by the invention has relatively good comprehensive performance, tensile strength of 17-37MPa, a glass-transition temperature of 30-39 DEG C, a maximum thermal decomposition temperature of 279-296 DEG C and elongation at break higher than 200%. A film prepared by the composite material has relatively good light transmission, so that the applied range, in the agricultural field, the food field and the packaging field, of the polypropylene carbonate is expanded; and the preparation method for the composite material is simple, and convenient for popularization and use.