Abstract:
PRODUCTION OF ORGANICALLY MODIFIED FINELY DIVIDED ALKALINE EARTH METAL AND EARTH METAL SILICATES AND SILICAS BY WET PRECIPITION OF SUCH SILICATES AND SILICAS FROM ALKALI METAL SILICATE SOLUTIONS WITH AQUEOUS SOLUTIONS OF ALKALINE EARTH METAL OR EARTH METAL SALTS OR ACIDS, PREFERABLY AT TEMPARATURES BETWEEN ABOUT 10 AND 90* C. IN THE PRESENCE OF WATER SOLUBLE REACTIVE POLYMERIC MATERIALS, FOR INSTANCE, POLYMERS CONTAINING THE REACTIVE AMINO, HYDROXYL, CARBOXYL, AMIDE OR KETO GROUPS. THE THUS OBTAINED MODIFIED SILICATES AND SILICAS CAN BE FURTHER MODIFIED BY EFFECTING REACTIONS WITH THE REACTIVE GROUPS OF THE BOUND POLYMERS IN THE SILICATES AND SILICAS.
Abstract:
A finely divided organically modified silica is formed by adding an inorganic acid at an elevated temperature to an aqueous alkali methyl silicate solution in contact with a water-soluble reactive organic polymer which is present in an amount of from about 3 to about 24 percent by weight relative to the weight of the thus precipitated silica.
Abstract:
1,155,523. Organically - modified silica. DEUTSCHE GOLD-UND SILBER-SCHEIDEANSTALT. 16 June, 1967 [18 June, 1966], No. 27962/67. Heading C1A. Finely-divided organically modified silica is precipitated, preferably at 50-90‹ C., from a silicate solution, e.g. water glass, by an inorganic or organic acid in the presence of one or more water-soluble organic polymers capable of undergoing modification of their properties by chemical reactions and of combination with silica, e.g. polyvinyl alcohol, polyethylene imine, polyacrolein, polymethacrylic acid, polyethylene oxide, polyvinyl pyrrolidone, polyvinyl-3- methyl pyrrolidone, vinyl pyrrolidone/vinyl acetate copolymers, polyacrylamide. The polymer(s) may be dissolved in the reaction mixture before precipitation or gradually added thereto during precipitation; in some cases a pure silica core may be formed around an organicallymodified shell. The polymers may be caused to undergo organic reactions, e.g. substitution, addition, salt or complex formation, or may be refined by substantive, reactive or leuco dyes at any time after silica is first formed (although not necessarily precipitated): examples of such reactions are given.
Abstract:
1,139,620. Modified carbon black. DEUTSCHE GOLDUND SILBER-SCHEIDEANSTALT. 26 June, 1967 [24 June, 1966], No. 29323/67. Heading C1A. [Also in Division C4] A grey pigment comprising carbon black and a finely divided metal and/or metalloid oxide is obtained by activating the surface of the carbon black by reaction with a silicon or titanium halide, particularly the tetrachloride, and subsequently hydrolysing the activated carbon by introducing it either into water, or into a suspension of a finely divided precipitated or pyrogenic oxide of silicon and/or titanium and/or aluminium, or into a precipitation solution of a salt of one of these elements. The process is applicable to lamp black, of average particle size 100-200 mÁ, or to furnace black of 20-100 mÁ.