The present invention relates to the use of a combination of block polymers and particular compositions in a fluid injected under pressure into an oil-bearing rock, where: the fluid comprises solid particles and/or is brought into contact with solid particles within the oil-bearing rock following the injection thereof, the combination comprises (i) a polymer comprising: —a first block that is adsorbed on at least a portion of the particles; and —a second block, having a composition different from that of the first, and having a weight-average molecular weight of greater than 10 000 g/mol, for example greater than 100 000 g/mol, and that is soluble in the fluid; (ii) particles suitable for providing a gas barrier effect, preferably a latex and/or silica particles.

A method for applying a high friction surface roadway treatment and composition used therein is disclosed. The method comprises the steps of: providing a binder composition, comprising: 10-99.9 wt. % of a resin; 0.1-70 wt. % of an elastomer; heating the binder composition to a sufficient temperature to obtain a molten binder composition; applying a layer of the molten binder composition; and applying a layer comprising aggregate having a nominal maximum size of at least 1 mm, and an embedment depth of at least 30% in the molten binder composition layer. The resin is selected from hydrocarbon resins, alkyd resins, rosin resins, rosin esters, and combinations thereof.

A method for applying a high friction surface roadway treatment and composition used therein is disclosed. The method comprises the steps of: providing a binder composition, comprising: 10-99.9 wt. % of a resin; 0.1-70 wt. % of an elastomer; heating the binder composition to a sufficient temperature to obtain a molten binder composition; applying a layer of the molten binder composition; and applying a layer comprising aggregate having a nominal maximum size of at least 1 mm, and an embedment depth of at least 30% in the molten binder composition layer. The resin is selected from hydrocarbon resins, alkyd resins, rosin resins, rosin esters, and combinations thereof.

The present invention relates to the use of sequential copolymers (P), comprising at least one chain (C) capable of being obtained by micellar polymerization, for keeping solid particles (p) in suspension in a fluid (F) where said chain (C) is soluble.

A cement slurry may include an aqueous phase; a cement precursor material; and a hydrophilic branched star polymer. The hydrophilic branched star polymer is a crosslinked, polymerized reaction product of crosslinker C and hydrophilic monomer A and hydrophilic/hydrophobic monomer B and optionally hydrophilic/hydrophobic monomer D. The crosslinked polymerized reaction product includes a plurality of block copolymer segments of hydrophilic monomer A and hydrophilic/hydrophobic monomer B interconnected via crosslinker C; a plurality of block copolymer segments of hydrophilic monomer A, hydrophilic monomer B, and hydrophilic/hydrophobic monomer D interconnected via crosslinker C; or combinations thereof.

A cement slurry may include an aqueous phase; a cement precursor material; and a hydrophilic branched star polymer. The hydrophilic branched star polymer is a crosslinked, polymerized reaction product of crosslinker C and hydrophilic monomer A and hydrophilic/hydrophobic monomer B and optionally hydrophilic/hydrophobic monomer D. The crosslinked polymerized reaction product includes a plurality of block copolymer segments of hydrophilic monomer A and hydrophilic/hydrophobic monomer B interconnected via crosslinker C; a plurality of block copolymer segments of hydrophilic monomer A, hydrophilic monomer B, and hydrophilic/hydrophobic monomer D interconnected via crosslinker C; or combinations thereof.

This document relates to methods for preventing or inhibiting the cracking or explosion of cement in an oil well using cement compositions that contain polyrotaxane additives. The cement compositions containing the polyrotaxane additives exhibit increased resiliency to cracking as compared to the same cement without the polyrotaxane additive.

A fluorescent polycarboxylate superplasticizer and a preparation method thereof. The preparation process of the polycarboxylate superplasticizer is as follows. Firstly, a redox radical polymerization is performed on a monomer of an unsaturated acid and a derivative thereof, and an unsaturated polyether monomer to form a polycarboxylate superplasticizer pre-product. Then, the polycarboxylate superplasticizer pre-product is subjected to an esterification reaction with an organic molecule having a fluorescent property to obtain the fluorescent polycarboxylate superplasticizer. The method effectively reduces the reaction difficulty and makes the reaction rapid and efficient. The fluorescent polycarboxylate superplasticizer is non-toxic and non-polluting, and has good controllability in the production process and less side reactions. The fluorescent polycarboxylate superplasticizer can be applied to different kinds of cement, having a high water-reducing rate, and a relatively high cost performance and competitive advantage.

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.

The present invention relates to the use of a combination of block polymers and particular compositions in a fluid injected under pressure into an oil-bearing rock, where: the fluid comprises solid particles and/or is brought into contact with solid particles within the oil-bearing rock following the injection thereof, the combination comprises (i) a polymer comprising: —a first block that is adsorbed on at least a portion of the particles; and —a second block, having a composition different from that of the first, and having a weight-average molecular weight of greater than 10 000 g/mol, for example greater than 100 000 g/mol, and that is soluble in the fluid; (ii) particles suitable for providing a gas barrier effect, preferably a latex and/or silica particles.