A composite cementitious feedstock comprises discrete elements. Each discrete element includes mineral rock agglutinates having irregular surface regions and cavities. Super absorbent polymer (SAP) particles and cement particles are disposed on the irregular surface regions and in the cavities. A binder coheres the agglutinates, SAP particles, and cement particles.

Disclosed is a composite gypsum board comprising a board core comprising set gypsum sandwiched between face and back cover sheets. The composite gypsum board also comprises an intermediate sheet between the board core and the face cover sheet, with a thin, dense gypsum layer disposed between the intermediate sheet and the face cover sheet. Optionally, a second dense gypsum layer can be disposed between a first major side of the board core and the back cover sheet. Also disclosed is a method of preparing a composite gypsum board in which an intermediate sheet is applied over a dense gypsum layer disposed on a face cover sheet. A back cover sheet is applied to the other major side of the board core, with a second dense gypsum layer optionally disposed therebetween.

Disclosed is a composite gypsum board comprising a board core comprising set gypsum sandwiched between face and back cover sheets. The composite gypsum board also comprises an intermediate sheet between the board core and the face cover sheet, with a thin, dense gypsum layer disposed between the intermediate sheet and the face cover sheet. Optionally, a second dense gypsum layer can be disposed between a first major side of the board core and the back cover sheet. Also disclosed is a method of preparing a composite gypsum board in which an intermediate sheet is applied over a dense gypsum layer disposed on a face cover sheet. A back cover sheet is applied to the other major side of the board core, with a second dense gypsum layer optionally disposed therebetween.

Described is a method of preparing foams, wherein a suspension comprising an aqueous liquid, particles and at least one surfactant is provided, wherein the at least one surfactant at least partially hydrophobizes a surface of the particles, and wherein the suspension comprising the particles having the at least partially hydrophobized surface is foamed. The at least one surfactant is selected from surfactants having a backbone chain comprising at least nine carbon atoms, the at least one surfactant preferably being an amphiphilic molecule consisting of a tail coupled to a head group, wherein the tail comprises the backbone chain comprising at least nine carbon atoms.

Described is a method of preparing foams, wherein a suspension comprising an aqueous liquid, particles and at least one surfactant is provided, wherein the at least one surfactant at least partially hydrophobizes a surface of the particles, and wherein the suspension comprising the particles having the at least partially hydrophobized surface is foamed. The at least one surfactant is selected from surfactants having a backbone chain comprising at least nine carbon atoms, the at least one surfactant preferably being an amphiphilic molecule consisting of a tail coupled to a head group, wherein the tail comprises the backbone chain comprising at least nine carbon atoms.

A delayed-expansion cement mixture or slurry of hydraulic cement contains an expanding agent having hydrophobically modified surfaces with a hydrophobic and/or self-assembling film. A method to delay expansion of cement involves treating the expanding agent with a self-assembling film precursor compound, making the slurry with cement and water, and setting and expanding the cement. A cementing method places the mixture or slurry downhole where it is hardened and expanded.

A delayed-expansion cement mixture or slurry of hydraulic cement contains an expanding agent having hydrophobically modified surfaces with a hydrophobic and/or self-assembling film. A method to delay expansion of cement involves treating the expanding agent with a self-assembling film precursor compound, making the slurry with cement and water, and setting and expanding the cement. A cementing method places the mixture or slurry downhole where it is hardened and expanded.

A variety of systems, methods and compositions are disclosed, including, in one method, a method for well treatment may comprise providing a treatment fluid comprising an aqueous base fluid; and a nanofribril cellulose additive, wherein the nanofribril cellulose additive comprises nanofribril cellulose and a surfactant adsorbed onto a surface of the nanofribril cellulose; and introducing the treatment fluid into a well bore penetrating a subterranean formation. Additional systems, methods and compositions are also disclosed.

A variety of systems, methods and compositions are disclosed, including, in one method, a method for well treatment may comprise providing a treatment fluid comprising an aqueous base fluid; and a nanofribril cellulose additive, wherein the nanofribril cellulose additive comprises nanofribril cellulose and a surfactant adsorbed onto a surface of the nanofribril cellulose; and introducing the treatment fluid into a well bore penetrating a subterranean formation. Additional systems, methods and compositions are also disclosed.

A variety of systems, methods and compositions are disclosed, including, in one method, a method for well treatment may comprise providing a treatment fluid comprising an aqueous base fluid; and a nanofribril cellulose additive, wherein the nanofribril cellulose additive comprises nanofribril cellulose and a surfactant adsorbed onto a surface of the nanofribril cellulose; and introducing the treatment fluid into a well bore penetrating a subterranean formation. Additional systems, methods and compositions are also disclosed.