Cement slurries are provided for use in cementing oil and gas wells. The cement slurry comprises API Class C or Class H Portland cement and a pozzolan selected from the group consisting of pumice and mixtures of pumice and fly ash. Pumice is present in the mixtures in amounts at least about 40 wt % of the pozzolan. The weight ratio of the pozzolan to the cement is from about 35:65 to about 70:30. The novel cement slurries preferably will not comprise any additional lime, including hydrated lime, or other activators.

Cement slurries are provided for use in cementing oil and gas wells. The cement slurry comprises API Class C or Class H Portland cement and a pozzolan selected from the group consisting of pumice and mixtures of pumice and fly ash. Pumice is present in the mixtures in amounts at least about 40 wt % of the pozzolan. The weight ratio of the pozzolan to the cement is from about 35:65 to about 70:30. The novel cement slurries preferably will not comprise any additional lime, including hydrated lime, or other activators.

A method of finishing an interior wall includes the steps of preparing a substrate of building panels including gypsum, cement or combinations thereof, the substrate having a surface, followed by applying a coating to the substrate, the coating having 1-30% by weight of a latex emulsion binder, 30-80% by weight calcium sulfate hemihydrate, up to about 8% by weight of a set inhibiting agent and 20-60% by weight water.

A composition of matter may include a cement precursor, a phosphazene oligomer and water. A method may include blending a phosphazene oligomer and a cement precursor to form a cement precursor mixture. The method may then include introducing water into the cement precursor mixture to form the cement slurry. A composition of matter may include a cured cement matrix having a polyphosphazene polymer distributed throughout the cement matrix. A method may include cementing a wellbore by introducing a cement slurry into a wellbore, where the cement slurry includes a phosphazene oligomer. The method then includes maintaining the cement slurry such that a cured cement sheath forms, the cement sheath having a polyphosphazene polymer.

A composition of matter may include a cement precursor, a phosphazene oligomer and water. A method may include blending a phosphazene oligomer and a cement precursor to form a cement precursor mixture. The method may then include introducing water into the cement precursor mixture to form the cement slurry. A composition of matter may include a cured cement matrix having a polyphosphazene polymer distributed throughout the cement matrix. A method may include cementing a wellbore by introducing a cement slurry into a wellbore, where the cement slurry includes a phosphazene oligomer. The method then includes maintaining the cement slurry such that a cured cement sheath forms, the cement sheath having a polyphosphazene polymer.

A composition for use as a latex cement additive, the composition comprising an aqueous latex, the aqueous latex comprising an aqueous fluid and a solid elastomer, where the solid elastomer is dispersed in the aqueous fluid; a liquid elastomer, the liquid elastomer having a viscosity between 50,000 cP and 300,000 cP at room temperature; and a surfactant, the surfactant operable to facilitate incorporation of the liquid elastomer into the aqueous latex.

A composition for use as a latex cement additive, the composition comprising an aqueous latex, the aqueous latex comprising an aqueous fluid and a solid elastomer, where the solid elastomer is dispersed in the aqueous fluid; a liquid elastomer, the liquid elastomer having a viscosity between 50,000 cP and 300,000 cP at room temperature; and a surfactant, the surfactant operable to facilitate incorporation of the liquid elastomer into the aqueous latex.

A composition for use as a latex cement additive, the composition comprising an aqueous latex, the aqueous latex comprising an aqueous fluid and a solid elastomer, where the solid elastomer is dispersed in the aqueous fluid; a liquid elastomer, the liquid elastomer having a viscosity between 50,000 cP and 300,000 cP at room temperature; and a surfactant, the surfactant operable to facilitate incorporation of the liquid elastomer into the aqueous latex.

A composition for use as a latex cement additive, the composition comprising an aqueous latex, the aqueous latex comprising an aqueous fluid and a solid elastomer, where the solid elastomer is dispersed in the aqueous fluid; a liquid elastomer, the liquid elastomer having a viscosity between 50,000 cP and 300,000 cP at room temperature; and a surfactant, the surfactant operable to facilitate incorporation of the liquid elastomer into the aqueous latex.

A composition for use as a latex cement additive, the composition comprising an aqueous latex, the aqueous latex comprising an aqueous fluid and a solid elastomer, where the solid elastomer is dispersed in the aqueous fluid; a liquid elastomer, the liquid elastomer having a viscosity between 50,000 cP and 300,000 cP at room temperature; and a surfactant, the surfactant operable to facilitate incorporation of the liquid elastomer into the aqueous latex.