METHOD FOR PREPARING SPHERICAL SILICA POWDER FILLER, AND RESULTING SPHERICAL SILICA POWDER FILLER AND APPLICATION THEREOF

摘要

The present invention relates to a method for preparing a spherical silica powder filler, comprising the following steps: performing hydrolytic condensation on an organic silicon compound to obtain polysiloxane precipitate, wherein the organic silicon compound comprises silane having the chemical formula of (R₁)_a(R₂)_b(R₃)_cSi(X)_d, wherein R₁, R₂, and R₃ are independently selected C1-18 hydrocarbyl groups or hydrogen atoms; X is a hydrolysable functional group; a, b, and c are 0, 1, 2, or 3; d is 1, 2, 3, or 4; and a+b+c+d=4; smashing and drying the polysiloxane precipitate to obtain siloxane angular powder; and melting and spherifying the siloxane angular powder into the spherical silica powder filler. The present invention also provides a spherical silica powder filler obtained by the method and an application thereof. The present invention takes the organic silicon compound as the starting material, and the resulting spherical silica powder filler does not contain radioactive elements such as uranium and thorium, and therefore, the requirement of low radioactivity is satisfied.