36results about How to "Low dosage" patented technology

The invention relates to a comb-shaped grafted copolymer cement dispersing agent. The comb-shaped grafted copolymer cement dispersing agent has the advantages of simple production technology, low mixing amount and high adaptability. The comb-shaped grafted copolymer cement dispersing agent is prepared through the following steps: preparing the comb-shaped grafted copolymer cement dispersing agent through the free radical copolymerization reaction of monomers A shown by a general formula (1) and monomers B shown by a general formula (2) in an aqueous medium; and setting the mol ratio of A to B to be 1:2 to 1:10. Amide nonionic base groups are introduced into the backbone of the grafted copolymer and are taken as the absorption base groups, thereby reducing the sensitivity of the grafted copolymer absorption characteristic to the variety and content of ions in the cement slurry, and consequently improving the adaptability of the grafted copolymer dispersing agent in the building engineering. The comb-shaped grafted copolymer cement dispersing agent has the advantages of simple production process, low mixing amount and high cement adaptability.

The invention provides a comb-shaped graft copolymer cement dispersant, which has the advantages of low mixing amount and strong temperature adaptability. The invention also provides a composite cement dispersant which comprises the comb-shaped graft copolymer cement dispersant. The comb-shaped graft copolymer cement dispersant is prepared through radical copolyreaction between unsaturated monomerand aqueous medium; the unsaturated monomer comprises unsaturated polyether macromer A and unsaturated phosphonate monomer B, wherein the unsaturated polyether macromer A is presented by a general formula (1), and the unsaturated phosphonate monomer B is presented by a general formula (2) or a general formula (3). The composite cement dispersant comprises the comb-shaped graft copolymer cement dispersant, and also comprises polycarboxylic acid admixture shown by a general formula (4), a general formula (5), a general formula (6) or a general formula (7). In the invention, water is used as medium, and a simple copolymerization technology is adopted for obtaining the comb-shaped graft copolymer cement dispersant with low mixing amount. The dispersibility of the comb-shaped graft copolymer cement dispersant is little influenced by the concentration of SO4<2-> and the temperature so that the comb-shaped graft copolymer cement dispersant has favorable adaptability for cement and environment.

The invention provides a liquid cement additive for reducing the content of water-soluble Cr<6+> in cement. The liquid cement additive has good Cr<6+> elimination ability, and also has the advantages of reasonable price, small mixing amount, and small influences on the performances of cement. The liquid cement additive comprises, by mass, 5-10% of sodium borohydride, 5-10% of sodium sulfite, 5-10% of sodium nitrite, 5-10% of sodium formate, 1-5% of polyglycerol, 0-15% of alcohol amine, 0.5-1% of NaOH, and the balance of water, wherein the alcohol amine is at least one of triethanolamine, triisopropanolamine, diethanol isopropanolamine and methyldiethanolamine, and the pH value of the liquid cement additive is 10-14. The liquid cement additive has good Cr<6+> elimination ability, and has the advantages of reasonable price, small mixing amount, and small influences on the performances (such as water requirement of normal consistency and intensity) of cement.