This invention provides low dust low density gypsum wallboard products having high total core void volumes, corresponding to low densities in the range of about 10 to 30 pcf. The wallboards have a set gypsum core formed between two substantially parallel cover sheets, the set gypsum core preferably having a total void volume from about 80% to about 92%, and made from a slurry including stucco, pregelatinized starch, and a naphthalenesulfonate dispersant. The combination of the pregelatinized starch and the naphthalenesulfonate dispersant also provides a glue-like effect in binding the set gypsum crystals together. The wallboard formulation, along with small air bubble voids (and water voids) provides dust control during cutting, sawing, routing, snapping, nailing or screwing down, or drilling of the gypsum-containing products. This invention also provides a method of making the low dust low density gypsum products including the introduction of soap foam in an amount sufficient to form a total void volume, including air voids, preferably from about 80% to about 92% in the set gypsum core, corresponding to a set gypsum core density from about 10 pcf to about 30 pcf. The wallboards produced by the method generate significantly less dust during working.

This invention provides low dust low density gypsum wallboard products having high total core void volumes, corresponding to low densities in the range of about 10 to 30 pcf. The wallboards have a set gypsum core formed between two substantially parallel cover sheets, the set gypsum core preferably having a total void volume from about 80% to about 92%, and made from a slurry including stucco, pregelatinized starch, and a naphthalenesulfonate dispersant. The combination of the pregelatinized starch and the naphthalenesulfonate dispersant also provides a glue-like effect in binding the set gypsum crystals together. The wallboard formulation, along with small air bubble voids (and water voids) provides dust control during cutting, sawing, routing, snapping, nailing or screwing down, or drilling of the gypsum-containing products. This invention also provides a method of making the low dust low density gypsum products including the introduction of soap foam in an amount sufficient to form a total void volume, including air voids, preferably from about 80% to about 92% in the set gypsum core, corresponding to a set gypsum core density from about 10 pcf to about 30 pcf. The wallboards produced by the method generate significantly less dust during working.

The present invention provides methods of making an aqueous composition comprising polymerizing in the presence of one or more initiators at a pH of from 1 to 5 an aqueous monomer mixture of an aqueous medium and one or more acrylic or vinyl macromonomers containing an oxyalkylene chain group in the presence of one or more carboxylic acid group containing fluids chosen from a copolymerizable ethylenically unsaturated carboxylic acid, a polymeric polycarboxylic acid and mixtures thereof, to form a brush polymer-containing oxyalkylene side chain groups, wherein, the polymerizing takes place at a solids content ranging from 8 to 60 wt.%, and, combining one or more aromatic cofactors with the aqueous composition. In addition, the present invention provides aqueous compositions of brush polymers containing oxyalkylene side chain groups having more than one phase domain and a substantially reduced viscosity to enable processing with far less energy input or water waste.

The present invention provides methods of making an aqueous composition comprising polymerizing in the presence of one or more initiators at a pH of from 1 to 5 an aqueous monomer mixture of an aqueous medium and one or more acrylic or vinyl macromonomers containing an oxyalkylene chain group in the presence of one or more carboxylic acid group containing fluids chosen from a copolymerizable ethylenically unsaturated carboxylic acid, a polymeric polycarboxylic acid and mixtures thereof, to form a brush polymer-containing oxyalkylene side chain groups, wherein, the polymerizing takes place at a solids content ranging from 8 to 60 wt.%, and, combining one or more aromatic cofactors with the aqueous composition. In addition, the present invention provides aqueous compositions of brush polymers containing oxyalkylene side chain groups having more than one phase domain and a substantially reduced viscosity to enable processing with far less energy input or water waste.

This invention discloses a double-liquid grouting slurry, its technology and application for super large diameter underwater shield engineering under high water pressure condition. The materials of slurry I are: 35-45 parts of cement clinker; 15-25 parts of slag; 24-35 parts of fly ash; 15-25 parts of steel slag; 5-15 parts of bentonite; 4-10 parts of limestone tailing; 0.3-2.0 parts of water reducing agent; 0.5-2.5 parts of cellulose. The materials of slurry II are: 0.2-3.8 parts of short-cut fiber; 96-99 parts of sodium silicate solution; 0.8-4.8 parts of viscous polymers. This invention generates the double-liquid slurry preparation process including crushing-screening-milling-group mixing-grouped mixing at different speeds, the volume ratio of slurry I and II is 1:1-10:1 during grouting, and the slurry is injected into the shield void through the six-point position technology at the shield tail and 3+2+1 segment splicing synchronous grouting techniques.

An anti-corrosive concrete grouting material for coastal structure connection and a method for preparing the same, belonging to the technical field of anti-corrosion of coastal assembled structure connectors. The grouting material includes the following components: expansible compound cement, slag sand, fly ash (FA), polyvinyl alcohol (PVA) (containing an oxidant and a catalyst), graphene oxide (GO), a water reducer, an adjusting admixture, a defoaming agent, a mineral admixture and water. A shrinkage-free effect of the grouting material is realized through internal curing of GO-PVA hydrogel, micro-expansion of the compound cement and shrinkage reduction effect of the FA; an energy storage effect of a GO-PVA hydrogel micro-capacitor is exerted to avoid formation of a reinforcement corrosion micro-battery in a grouting material sleeve, a reinforcement corrosion self-immune effect is achieved, seawater corrosion resistance of the grouting material is improved by the slag sand, and it has huge economic and environmental protection benefits.

An anti-corrosive concrete grouting material for coastal structure connection and a method for preparing the same, belonging to the technical field of anti-corrosion of coastal assembled structure connectors. The grouting material includes the following components: expansible compound cement, slag sand, fly ash (FA), polyvinyl alcohol (PVA) (containing an oxidant and a catalyst), graphene oxide (GO), a water reducer, an adjusting admixture, a defoaming agent, a mineral admixture and water. A shrinkage-free effect of the grouting material is realized through internal curing of GO-PVA hydrogel, micro-expansion of the compound cement and shrinkage reduction effect of the FA; an energy storage effect of a GO-PVA hydrogel micro-capacitor is exerted to avoid formation of a reinforcement corrosion micro-battery in a grouting material sleeve, a reinforcement corrosion self-immune effect is achieved, seawater corrosion resistance of the grouting material is improved by the slag sand, and it has huge economic and environmental protection benefits.

A dispersant composition includes a) at least one polymer constituted of monomers having naphthalene ring and/or melamine; b). at least one polymer having carboxylic acid and/or phosphoric acid group and/or any group that is hydrolyzed into carboxylic or phosphoric; and c). at least one polymer having a structure of Formula I: ##STR00001##
R.sup.1 is hydrogen or alky group having carbon number not less than 1, cycloalkyl or cycloalkenyl group having carbon number not less than 3, alkenyl group having carbon number not less than 2, aryl group having carbon number not less than 6; R.sup.2 is hydrogen or alky group having carbon number from 1 to 3; A is alkylene group having carbon number from 3 or 4; m and n are positive numbers wherein m is more than n and the sum of m and n is more than 9 and less than 12. Also provided is a method of using the dispersant composition in a mortar or concrete, and the weight percentage of the dispersant composition is from 0.01% to 2.5% based on the weight of cement in mortar. Further provided is an aqueous composition including the dispersant composition.

A dispersant composition includes a) at least one polymer constituted of monomers having naphthalene ring and/or melamine; b). at least one polymer having carboxylic acid and/or phosphoric acid group and/or any group that is hydrolyzed into carboxylic or phosphoric; and c). at least one polymer having a structure of Formula I: ##STR00001##
R.sup.1 is hydrogen or alky group having carbon number not less than 1, cycloalkyl or cycloalkenyl group having carbon number not less than 3, alkenyl group having carbon number not less than 2, aryl group having carbon number not less than 6; R.sup.2 is hydrogen or alky group having carbon number from 1 to 3; A is alkylene group having carbon number from 3 or 4; m and n are positive numbers wherein m is more than n and the sum of m and n is more than 9 and less than 12. Also provided is a method of using the dispersant composition in a mortar or concrete, and the weight percentage of the dispersant composition is from 0.01% to 2.5% based on the weight of cement in mortar. Further provided is an aqueous composition including the dispersant composition.

A cementitious blend composition and a concrete mix composition preferable for making concrete resistant to high temperatures and alkaline conditions, particularly for making durable concrete for constructing an alumina digester tank in an aluminum smelter. The cementitious blend composition includes at least one hydraulic cement, silica fume (SF), and natural pozzolan (NP), wherein a weight percent ratio of at least one hydraulic cement:SF:NP in the cementitious blend composition lies in the range of (24-63):(5-44):(32-40) with the sum of the weight percentages of the at least one hydraulic cement, the SF, and the NP not exceeding 100%. The concrete mix composition comprises water and the cementitious blend composition, wherein a weight ratio of the water to the cementitious blend composition is 0.2-0.5, and wherein the concrete mix composition has a content of the cementitious blend composition of 400-550 kg/m.sup.3.