Preparation method and application of composite single-shell hollow microsphere filler

The invention belongs to the technical field of inorganic transition metal oxides, and particularly relates to a preparation method of a composite single-shell hollow microsphere filler with a micro-size hollow shell structure, PMMA microspheres are used as a hard template, tetrabutyl titanate is used as a precursor, the surface of the PMMA microspheres is coated with a TiO2 layer by a sol-gel method, the formed PMMA coated TiO2 is subjected to high-temperature calcination treatment, and the composite single-shell hollow microsphere filler with the micro-size hollow shell structure is obtained. The preparation method comprises the following steps: preparing titanium dioxide hollow microspheres with uniform particle size distribution, high light reflectivity and low thermal conductivity, converting the crystal type of TiO2 from an anatase type to a rutile type according to different calcination temperatures, carrying out a heat insulation performance test on H-TiO2 prepared by using titanium sol with different