CHROMATOGRAPHIC ADSORBENTS

Chromatographic adsorption material is prepared containing as the adsorption agent, powdered silica gel, kieselguhr, aluminium oxide, magnesium silicate, calcium phosphate, cellulose powder, a polyamide powder, or a polycarbonate powder and, as a bonding agent therefor, from 0.1 to 10% by weight of one or more polymers selected from carboxyl group-containing vinyl polymers and their salts, polyacrylamide, polymethacrylamide, polyacrylamides and polymethacrylamides mono- or di-substituted at the amide nitrogen by alkyl groups containing from 1-4 carbon atoms and copolymers of the monomers of these polymeric compounds. The bonding agent is thoroughly mixed with the adsorption agent in the presence of the desired amount of water. The resultant mixture can be coated on to supporting plates, but can also be used in the form of self-supporting sheets and thin rods. The adsorption agent is dried and activated by heating at 100-150 DEG C. following which the coatings have good adhesions to the supporting backings and are mechanically strong, flexible, and abrasion resistant. The adsorption material may also contain from 2-7% by weight of an inorganic adhesive such as finely divided silica (3-30 mm ) or aluminium hydroxide. Various luminous substances may be added to aid the detection of chromatographically separated layers of colourless substances which absorb ultra-violet rays.ALSO:Chromatographic adsorption material comprising, as the adsorption agent, powdered silica gel, kieselguhr, aluminium oxide, magnesium silicate, calcium phosphate, cellulose, a polyamide, or polycarbonate and, as a binding agent therefor, from 0.1 to 10% by weight of one or more polymers selected from carboxyl group-containing vinyl polymers and their salts, polyacrylamide, polymethacrylamide, polyacrylamides and polymethacrylamides mono- or disubstituted at the amide nitrogen by alkyl groups containing from 1-4 carbon atoms, and copolymers of the monomers of these polymeric compounds. The bonding agent is throughly mixed with the adsorption agent in the presence of the desired amount of water. The resultant mixture can be coated onto supporting plates or sheets of plastic film. The adsorption agent is dried and activated by heating at 100-150 DEG C. The adsorption material may contain from 2-7% by weight of an inorganic adhesive such as silica of particle size 3-30mm whereas if the basic adsorption agent is aluminium oxide then finely divided aluminium hydroxide may be added as an inorg