30results about How to "Initiation temperature is low" patented technology

The invention relates to a high-adaptability multi-branched-chain amide imine type polycarboxylate based water reducer and a preparation method thereof, and belongs to the technical field of concreteadditives. The polycarboxylate based water reducer is composed of the following substances: polyether macromonomers, unsaturated acid monomers, branched-chain functional monomer methoxy polyethylene glycol mercaptoacetate, amide imine type functional monomer diethylenetriamine maleate, an initiator, a reducing agent and deionized water, wherein the molar ratio of the polyether macromonomers to theunsaturated acid monomers to the branched-chain monomers to the amide imine type monomers is 1:(2-5):(0.3-0.6):(0.5-1.0). The prepared water reducer has a relatively high water reducing rate and excellent slump retaining performance, and the problem of adaptability between cement concrete and the polycarboxylate based water reducer is also solved. The invention further provides a preparation method thereof. The preparation method comprises four steps, is scientific and reasonable, and is simple and feasible.

The invention discloses a method for preparing super absorbent resin by grafting and copolymerizing carboxymethyl potato pulp. The main process is as follows: under ice-water bath cooling, carrying out neutralization reaction by using sodium hydroxide liquor and polymerization inhibitor-removed acrylic acid, adding neutralized liquor into a reaction container which contains carboxymethyl potato pulp, acrylamide, potassium persulfate, sodium hydrogen sulfite, N, N'- methylene bisacrylamide and deionized water for sufficiently mixing uniformly, stirring under nitrogen gas protection, heating in water bath, stopping stirring while heating to 25-45 DEG C, preserving heat for 2 hours in boiling water bath, then stopping ventilating nitrogen gas, taking out a product and shearing the product into small blocks, drying in an oven of 40 DEG C-60 DEG C until weight is constant, crushing to obtain a product. Compared with water-absorbent resin on the market, the super absorbent resin prepared by the method disclosed by the invention has water absorption capacity which is greatly improved, and low preparation cost, and therefore, the method has a very good application prospect in water retention of arid area soil, desert prevention and treatment, gardening of agriculture and forestry, and the like.

The invention discloses an efficient slump retaining agent, which is prepared from the following components in parts by weight: 250-600 parts of a monomer A, 11-40 parts of a monomer B, 20-60 parts ofa monomer C, 5-15 parts of a monomer D, 1-20 parts of an initiator, 0.8-10 parts of a composite molecular weight regulator, 0.5-4 parts of vitamin C sodium and 300-700 parts of water, wherein the monomer A is any one or a mixture of more of isopentenyl polyethylene glycol ether, hydroxybutyl vinyl polyethylene glycol ether and ethoxy vinyl polyethylene glycol ether, the monomer B is any one or amixture of two of acrylic acid, fumaric acid, itaconic acid and maleic anhydride, the monomer C is any one or a mixture of more of hydroxyethyl acrylate, hydroxypropyl acrylate, methacryloyloxy phosphate and hydroxyethyl methacrylate, the monomer D is diacrylamide dimethyl propanesulfonic acid or acrylamide, and the composite molecular weight regulator is mercaptoethanol. The components are subjected to a stirring reaction to obtain the product. The efficient slump retaining agent provided by the invention is good in slump retaining performance, small in performance fluctuation and excellent in adaptability, and can effectively meet the slump retaining requirements of concrete in various regions.

The invention discloses a method for preparing nitrogen and potassium contained superabsorbent resin from carboxymethyl potato residues. The method comprises the main process steps of enabling a potassium hydroxide solution and polymerization inhibitor removed acrylic acid to be subjected to neutralization reaction under the cooling of ice-water bath; adding the neutralized solution into a reaction vessel filled with carboxymethyl potato residues, acrylamide, potassium persulfate, sodium hydrogen sulfite, N, N'-methylenebisacrylamide and deionized water; stirring under the protection of nitrogen gas, heating in water bath, stopping stirring at the temperature of 25-45 DEG C, and preserving heat in boiling water bath for 1-2h; then, stopping introducing nitrogen gas, taking out a product, shearing the product into small blocks, drying the small blocks in a drying oven with the temperature of 40-60 DEG C until the weights of the small blocks are constant, and smashing to obtain the nitrogen and potassium contained superabsorbent resin prepared from carboxymethyl potato residues. Compared with the like product, the superabsorbent resin prepared by using the method disclosed by the invention is greatly improved in water absorbing capacity, low in preparation cost and favorable in application prospect on the aspects such as water retention of soil in drought regions, desert control, plant growth and the like.

The invention discloses fluorescently-labeled polyacrylamide, and a preparation method and application thereof as a visual soil structure improver. The method comprises the steps: initiating an acrylamide monomer and a modified fluorescent monomer FL (4-(N'-methyl-1-piperazinyl)-N-propyl-1,8-naphthalenedicarbonyl allyl chloride quaternary ammonium salt) by using an initiator, and carrying out freeradical copolymerization reaction to generate the fluorescently-labeled polyacrylamide. The material can emit macroscopic green fluorescence under the excitation of ultraviolet light. When the material is applied to soil, the migration of polyacrylamide in the soil can be visualized, and a method is provided for subsequent research on the action of polyacrylamide in the soil. Polyacrylamide contains a large number of amide groups, and can adsorb soil particles due to hydrogen bond interaction, so that tiny particles in polyacrylamide are aggregated into stable large aggregates, the volume weight of soil is reduced, soil hardening and water and soil loss are effectively prevented and treated, and a good soil improvement effect is achieved.

The present invention discloses preparation process of polyammonium dialkyldiallyl halide. By using ammonium dialkyldiallyl halide with high purity as material, and through adding initiator and complexing agent at relatively low temperature and stepped temperature raising for slow polymerization and high temperature curing, polyammonium dialkyldiallyl halide with relatively high molecular weight is prepared. The molecular weight is regulated through regulating the initial monomer content and initiator amount in the reaction system. The process has industrial application foreground, high technological stability, easy operation and other advantages, and the product has relatively high molecular weight.

The invention discloses a method for preparing super absorbent resin from sorghum straws, the method comprises the following steps: S1, soaking crushed sorghum straw powder in a low-concentration alkali solution, then adding a high-concentration alkali solution for alkalization reaction, and then adding sodium chloroacetate and the high-concentration alkali solution for etherification reaction to obtain carboxymethyl sorghum cellulose; s2, mixing acrylic acid and a neutralizer for a neutralization reaction, and obtaining acrylic acid and a salt solution thereof; s3, mixing the carboxymethyl sorghum cellulose with an oxidizing agent, a cross-linking agent, acrylic acid, a salt solution of the acrylic acid and a reducing agent, introducing nitrogen, and carrying out a stirring reaction; and S4, after the reaction is finished, heating and carrying out heat preservation. The water absorption performance and the water retention performance of the super absorbent resin prepared by the method are 2-3 times of those of similar products in the current market, and the water absorption is up to 1250-1550g/g. The method is simple in process and low in preparation cost, and has huge application prospects in the industries of soil moisture retention, desert control, agriculture and forestry, flower transportation and the like.

A radiating polymerization process for preparing nano microcapsules includes such steps as proportioning core, monomer, emulsifier and water, mixing core with monomer, adding emulsifier and water, strong stirring for 15-45 min, high-energy ray radiating while aerating nitrogen gas for polymerizing reaction for 5-6 hr, filtering, and neutralizing to 5-7 of pH value with diluted ammonia solution.