An early-strength polycarboxylate superplasticizer with an MOF structure and a preparation method thereof are provided. The preparation method includes the following steps: 1) performing an amidation reaction on amine-containing nanocrystalline MOFs and a halogen acyl halide organic molecule to form the halogen-containing ATRP initiator; 2) performing an ATRP reaction on the obtained ATRP initiator, an unsaturated ester monomer, an unsaturated polyether macromonomer and a transition metal complex to obtain the early-strength polycarboxylate superplasticizer with the MOF structure. The present invention regulates the number and length of branch chains and product performance by controlling the number of amine groups contained in the nanocrystalline MOFs and ATRP, and has the advantages of rapid reaction, high efficiency, non-toxic and non-pollution, and simple operation. The prepared early-strength polycarboxylate superplasticizer with the MOF structure has early-strength performance and stable product performance.

The invention discloses a method of producing metal-organic framework (MOF) incorporated concrete to capture CO.sub.2 and reduce carbon footprint, the method comprising mixing cement, a plurality of fine aggregates and a plurality of coarse aggregates for a predefined time under ambient conditions in a concrete mixer to form a dry concrete mix, mixing water in the dry concrete mix to form a wet concrete mix, incorporating MOF homogeneously into the wet concrete mix to form the MOF incorporated concrete, mixing the MOF incorporated concrete for two minutes and casting the MOF incorporated concrete by placing the MOF incorporated concrete into a mold, and curing the MOF incorporated concrete via a three-stage curing process. A quantity of the MOF in concrete is 3, 6 and/or 9% by cement mass.

This document relates to methods for improving the tensile and elastic properties of cement of an oil well using cement compositions that contain sliding-ring polymer additives. The cement compositions containing the sliding-ring polymer additives exhibit increased stiffness while having a minimum impact on compressive strength, as compared to the same cement without the sliding-ring polymer additive.

A process of manufacturing NH2-MIL-125(Ti) for use in mitigating ingress of chlorine ions in concrete, comprising dissolving 2-amino-benzene dicarboxylic acid in a 1:1 ratio of dimethylformamide and methanol, adding a titanium (IV) isopropoxide to the mixture at 150° C. with constant stirring to form NH2-MIL-125(Ti), submerging the NH2-MIL-125(Ti) in dichloromethane for about 3 hours and separating the NH2-MIL-125(Ti). NH2-MIL-125(Ti) produced is activated and ready for use in cement-based concrete structures. NH2-MIL-125(Ti) is enabled to reduce the ingress of chlorine ions in concrete by at least 20%.

Process for the production composite articles, comprising the steps of: a) providing a curable mixture comprising: 30-95 wt % of filler material, —5-70 wt % of resin, selected from unsaturated polyester resins, vinyl ester resins, (meth)acrylate resins, and combinations thereof, 0.5-10 phr of at least one peroxyester, 0.1-2.0 phr of at least one organic hydroperoxide, the weight ratio peroxyester/organic hydroperoxide being below 14.0, the curable mixture being essentially free of ketone peroxide, b) shaping the mixture, and c) heating the shaped mixture at a temperature in the range 60-100° C. to affect hardening of the resin and the formation of an article.

This document relates to methods for improving the tensile and elastic properties of cement of an oil well using cement compositions that contain sliding-ring polymer additives. The cement compositions containing the sliding-ring polymer additives exhibit increased stiffness while having a minimum impact on compressive strength, as compared to the same cement without the sliding-ring polymer additive.

This document relates to methods for preventing or inhibiting the formation of micro-cracks and fractures in the cement of an oil well using cement compositions that contain cross-linked polyrotaxane additives. The cement compositions containing the cross-linked polyrotaxane additives exhibit increased stiffness without suffering a decrease in compressive strength, as compared to the same cement without the cross-linked polyrotaxane additive.

The present invention relates to a process for preparing a metal-chelate retarder by a sol-gel method. The method comprises the following steps: weighing calcium nitrate tetrahydrate, aluminum nitrate nonahydrate and ferric nitrate nonahydrate according to a certain mass ratio and adding them into deionized water; placing the mixed solution on a magnetic stirrer and stirring the mixed solution evenly; adding citric acid monohydrate or gluconic acid, ethylene glycol or glycerol, and placing the mixed solution into a water bath to react to obtain the metal-chelate retarder. The process of the present invention has a reliable principle, overcomes the defects of long production period, complex preparation and the like of the existing retarders, has the advantages of simple process operation, cheap and easily available raw materials, and short production period. The prepared retarder has wide temperature adaptation range and adjustable thickening time, is suitable for large-scale industrial production, and has a wide market application prospect.

The present invention relates to a process for preparing a metal-chelate retarder by a sol-gel method. The method comprises the following steps: weighing calcium nitrate tetrahydrate, aluminum nitrate nonahydrate and ferric nitrate nonahydrate according to a certain mass ratio and adding them into deionized water; placing the mixed solution on a magnetic stirrer and stirring the mixed solution evenly; adding citric acid monohydrate or gluconic acid, ethylene glycol or glycerol, and placing the mixed solution into a water bath to react to obtain the metal-chelate retarder. The process of the present invention has a reliable principle, overcomes the defects of long production period, complex preparation and the like of the existing retarders, has the advantages of simple process operation, cheap and easily available raw materials, and short production period. The prepared retarder has wide temperature adaptation range and adjustable thickening time, is suitable for large-scale industrial production, and has a wide market application prospect.

A composite plate is mainly made from the following raw materials in percentage by weight: 35% to 45% of calcium carbonate, 45% to 55% of cullet, 5% to 15% of unsaturated polyester resin, 0.1% to 1% of a curing agent, 0.1% to 1% of an auxiliary agent, wherein a ratio of an amount of the calcium carbonate to an amount of the cullet is 0.75%. The invention employs cullet, calcium carbonate, and resin as the main raw materials to prepare an artificial stone plate; no natural quartz is used, and hence the raw material cost is low. A reasonable ratio of cullet to calcium carbonate reduces the use of resin, which further reduces the raw material cost. Through a reasonable combination of different raw materials, the composite plate of the invention has physical and chemical properties and decorative abilities that are similar to those of traditional artificial quartz stone.