METHOD FOR PRODUCING ZETA-NEGATIVE NANODIAMOND DISPERSION AND ZETA-NEGATIVE NANODIAMOND DISPERSION Russian patent published in 2019 - IPC C01B32/15 C01B32/28 B82B3/00 B82B1/00 B82Y40/00 

FIELD: nanotechnologies.

SUBSTANCE: invention relates to nanotechnology. Carboxylated nanodiamond powder is suspended in a liquid medium from a group including polar protic or aprotic solvents, bipolar aprotic solvents, ionic liquids or mixtures thereof, for example, in water. Zeta-potential of the resulting suspension is more than -30 mV at pH from 3 to 5. After that, the pH of the suspension is adjusted to at least 7 by adding a Bronsted or Lewis base, preferably ammonium hydroxide, ammonia. Suspension is then treated with ultrasound and ground in a ball mill. Resulting dispersion contains more than 1 wt% of carboxylated nanodiamonds of single-digit nanometer size and has a zeta potential of more than -35 mV, measured at a pH of more than 7. D90 average primary particle size distribution in the resulting dispersion is 2–30 nm.

EFFECT: method for producing a zeta-negative nanodiamond dispersion and a zeta-negative nanodiamond dispersion are disclosed.

23 cl, 7 dwg, 1 tbl