Abstract: The present application provides a preparation method for a thermally expandable microsphere containing hydrophilic organic-modified colloidal silicon dioxide. In the preparation method, hydrophilic organic-modified colloidal silicon dioxide is mixed with a mixture of a monomer material capable of polymerizing to form a thermoplastic polymer shell and at least one foaming agent to form an emulsion, and the emulsion is polymerized to form the thermally expandable microsphere. Surface-modified colloidal silicon dioxide with hydrophilic organic group in the present application has good salt tolerance stability, can be stabilized in brine and is beneficial to the preparation of the thermally expandable microsphere; and the prepared microsphere has a narrow particle size distribution, can be easily dispersed in water and an organic system, and has good wettability. The application also relates to a thermally expandable microsphere and use thereof.

Abstract: EV-grade high-purity lithium sulfide and a preparation method therefor, including: A. mixing and well grinding a lithium source and a sulfur source to obtain a mixture; B. primary reaction: mixing the mixture with hydrazine hydrate in an inert atmosphere and reacting to obtain an intermediate slurry; C. secondary reaction: performing secondary reaction on the intermediate slurry in the inert atmosphere and drying to obtain a crude lithium sulfide product; and D. calcining and ball milling the crude lithium sulfide product to obtain the EV-grade high-purity lithium sulfide. The purity of the EV-grade high-purity lithium sulfide prepared by the method is above 99.9%, the whiteness thereof is above 80, and D50?15 ?m; the method is characterized by simple process operation, high safety, low energy consumption, low equipment requirements and low production cost; therefore, the method is suitable for industrial production.