The invention relates to a preparation method of ultrafine needle-like
wollastonite modified spherical
silicon dioxide composite
powder, wherein the method comprises the steps: treating high-quality needle-like
wollastonite raw ore and quartzite raw ore to obtain needle-like
wollastonite powder and spherical quartzite
powder; adding a composite dispersing agent into the needle-like wollastonite powder and the spherical quartzite powder to prepare wollastonite powder
slurry and quartzite powder
slurry; and making the two slurries into a composite
slurry,
drying, depolymerizing and scattering, and carrying out
surface modification by a composite modifier to obtain the special ultrafine needle-like wollastonite modified spherical
silicon dioxide composite powder for an
epoxy pouring
sealant.The needle-like wollastonite powder and spherical
silicon dioxide are subjected to superfine
wet grinding, and then slurry compounding is carried out, so the problems of poor
dispersity, low
bonding strength, low
adhesive strength and the like caused by
single use of one kind of powder in the
epoxy pouring
sealant are avoided, the needle-like wollastonite powder and the spherical
silicon dioxide are interspersed and accumulated in the pouring
sealant, the
dispersity and the suspension property of the powder are improved, the pouring sealant is compact in pouring, and the heat-conducting property of the sealant is improved.