Abstract: A networked polymer/clay alloy is produced from a monomer/clay mixture comprising a monomer, a cross-linking agent and clay particles. An initiator means is used to initiate polymerization of the monomer/clay mixture. The clay is chemically integrated with the polymer such that, on exposure to water, the networked polymer/clay alloy swells with substantially no clay separating from the alloy.

Abstract: A reinforced networked polymer/clay alloy composite is produced by contacting a monomer/clay mixture with a reinforcing agent. The monomer/clay mixture comprises a monomer, a cross-linking agent and clay particles. An initiator means is used to initiate polymerization of the monomer/clay mixture, while the cross-linking agent concurrently acts to network oligomeric and polymeric species formed during polymerization to produce a networked polymer/clay alloy in the presence of the reinforcing agent. The networked polymer/clay alloy is intimately integrated with the reinforcing agent such that, on exposure to water, the networked polymer/clay alloy swells with substantially no clay separating from the composite.

Abstract: A method is provided for blocking high permeability channels in subterranean geological formations, using swelling clay. A slurry is prepared by mixing swelling clay, such as bentonite, into an aqueous solution containing the salt of certain cations, which inhibit clay swelling. The cations K.sup.+, Ca.sup.2+ and Mg.sup.2+, among others, are inhibitive of clay swelling. The clay slurry is introduced into a geological formation, where it preferentially enters channels of high permeability. There the slurry is contacted by NaCl brine solution present in natural or injected drive fluids, and the inhibitive cations bound to the clay particles are replaced by Na.sup.+ ions, which attract water molecules and promote clay swelling. The Na.sup.+ -clay swells to up to 10 times its original volume, causing the slurry to acquire a gel-like consistency. The clay gel so formed is capable of blocking the flow of water, and can resist pressure of up to 500 kPa per meter.