FIELD: technology for silicium dioxide production useful as additive for polymer reinforcement.
SUBSTANCE: claimed method includes silicate reaction with acidifying agent to produce silicium dioxide slurry separation and drying of said slurry, wherein reaction is carried out according to the next steps: i) providing base aqueous solution with pH from 2 to 5, preferably from 2.5 to 5; ii) simultaneous addition silicate and acidifying agent to said base solution maintaining solution pH from 2 to 5, preferably from 2.5 to 5; iii) addition silicate only without acidifying agent to produce pH from 7 to 10, preferably from 7.5 to 9.5; (iv) simultaneous addition silicate and acidifying agent to reaction medium to maintain pH from 7 to 10, preferably from 7.5 to 9.5; (v) addition acidifying agent only without silicate to produce reaction medium pH below 6. Obtained high structured silicium dioxides have the next characteristics: CTAB specific surface (SCTAB) is 40-525 m2/g; BET specific surface (SBET) is 45-550 m2/g; width Ld ((d84-d16)/d50) of particle size distribution measured by XDC grading analysis after ultrasound grinding is at least 0.92; and such pore distribution that V(d95-d50)/V(d5-d100) is at least 0.66.
EFFECT: improved material for polymer reinforcement.
