41results about How to "Moderate reaction rate" patented technology

The invention relates to a high-elasticity environment-friendly polyvinyl chloride material composition as well as a preparation method and application of the composition. The composition contains the following raw material components in parts by weight: 100 parts of polyvinyl chloride resin, 0.5-15 parts of a stabilizer, 0.5-20 parts of a processing aid, 1-20 parts of a mass modifier, 0.1-10 parts of a lubricant, 0.5-20 parts of a filler and 0-5 parts of a pigment, wherein the K value of the polyvinyl chloride resin is 60-65; the stabilizer is at least one of a zinc-calcium stabilizer and a magnesium-aluminum-zinc stabilizer. According to the high-elasticity environment-friendly polyvinyl chloride material composition, a tin-containing stabilizer or a lead-containing stabilizer is not used, and meanwhile, the high-elasticity environment-friendly polyvinyl chloride material composition has excellent elasticity and strength performance and is good in color and luster and low in cost.

The present invention provides an acetylation method, using N,N-dimethylformamide as a solvent, inorganic cyanide as a side reaction inhibitor, in the presence of catalyst alkoxide or amino salt, saturated or unsaturated ketone or aldehyde compound The corresponding alkynyl alcohol compounds are obtained through the acetylation reaction, which has the advantages of moderate reaction rate, mild reaction and easy control, easy product separation, and solvent recovery.

The invention provides a preparation method of liquid polycarboxylate superplasticizer. Through a main body polymerization reaction, the polycarboxylate superplasticizer is prepared. The preparation method includes steps of (1), mixing polyoxyethylene polyoxypropylene ether and polyoxyethylene ether, and controlling temperature at 40-60 DEG C; stirring evenly and then adding initiator and mixtureof unsaturated carboxylic acid and chain transfer agent; (2), curing for 0.5-1 hour after completing step (1), cooling to obtain collapse-preventing type polycarboxylate superplasticizer. The main body polymerization reaction is carried out under a relative low temperature, the operability is strong, the condition is gentle, and the energy consumption is low; the preparation method is applied to compound polycarboxylate superplasticizer with excellent performance; the polycarboxylate superplasticizer prepared by the method is liquid state under the room temperature, the effective concentrationis up to 100%; the storage performance is stable, and the liquid polycarboxylate superplasticizer is suitable for long-distance transportation and use, thereby bringing good construction condition for concrete construction.

The invention discloses a method for producing iron oxide yellow. The method comprises the following steps: S1: adding calcium carbonate and water into a container; introducing air, and stirring; S2: adding ferrous chloride into the container, wherein the adding ratio of the calcium carbonate to the ferrous chloride is equal to or greater than the stoichiometric ratio of the calcium carbonate to the ferrous chloride; S3: heating a solution to be 80 DEG C to 85 DEG C; continually blowing the air in a process until the solution reacts to a needed color; carrying out thermal insulation for 30min to 60min, and discharging; S4: adding a diluted hydrochloric acid solution after discharging, so as to remove the calcium carbonate; S5: rinsing, carrying out press filtering, drying, crushing, and packaging to obtain a finished product. The method disclosed by the invention has the effects that the preparation method is simple, and the color consistency is good.

The invention relates to a modified calcium oxide expanding agent for shrinkage-compensating concrete. The agent is obtained by conducting mixing and ball milling on 0.1-20% by mass of modifier and 80-99.9% by mass of calcium oxide expanding agent; the calcium oxide expanding agent is an expanding agent containing free calcium oxide, and the free calcium oxide serves as a stable expansion source playing an expansion role; the modifier is prepared from one of or multiple substances of sodium sulfate or a crystalline hydrate thereof, ammonium sulfate or a crystalline hydrate thereof, ammonium bisulfate or a crystalline hydrate thereof, sodium sulfite or a crystalline hydrate thereof and ammonium sulfite or a crystalline hydrate thereof. The modified expanding agent can lower the early hydration rate of the expanding agent, reduce expansion energy loss in the concrete plastic stage, increase the expanding rate and reduce the contribution degree of the expanding agent to concrete temperature rise at the same time, the phenomenon that the concrete setting time is affected can be avoided, and the slump degree and expansion degree of concrete cannot be lowered. The preparation method is simple, batch production can be conducted, and no toxic dangerous goods are used as raw materials.

The invention belongs to the technical field of concrete admixture preparation, and in particular relates to a polycarboxylate water reducer and a preparation method thereof. The method comprises (1) preparing hydroxyethyl-terminated vinyl polyoxypropylene polyoxyethylene ether; (2) preparing polycarboxylate water reducer; the double-ended vinyl ether small monomers contain alkoxy groups and Contains double bonds; preferably, the vinyl ether monomer is ethylene glycol divinyl ether and / or diethylene glycol divinyl ether. The content of ultra-high molecular weight copolymer in the polycarboxylate water reducer prepared by the method is reduced, the relative molecular weight distribution is normal distribution, the molecular weight distribution is narrow, and there are almost no strong polar ultra-high molecular weight by-products; The reaction rate is controllable, the heat release is mild and stable, avoiding the local detonation phenomenon caused by high temperature during the polymerization reaction, and the monomer conversion rate can be increased to more than 95%.

The invention discloses a rigid polyurethane foam and a preparation method thereof. The preparation method of the rigid polyurethane foam comprises the following steps: premixing 100 parts by weight of hyperbranched polyurethane polyol with 1-10 parts by weight of foam stabilizer, adding 100-250 parts by weight of organic isocyanate or modified isocyanate to the pre-mixture and then curing at 30-100 DEG C for 12 hours to 3 days, thus obtaining the rigid polyurethane foam, wherein the hyperbranched polyurethane polyol is prepared by use of the following steps: reacting a polyhydroxylated compound with a diisocyanate monomer to obtain a first-generation hyperbranched prepolymer; on the basis of the isocyanate group content of the first generation hyperbranched prepolymer, adding the polyhydroxylated compound again and reacting to obtain the hyperbranched polyurethane polyol. The rigid polyurethane foam prepared by use of the method is high in strength, good in temperature resistance, good in dimensional stability and low in heat conductivity coefficient, and can be applied to the fields of thermal insulation, gap filling and supporting, wood-imitation materials and the like.

The invention discloses a preparation method of a superconducting Josephson junction, which belongs to the field of superconducting circuit components. The steps of the present invention are: 1) substrate pretreatment to obtain a clean substrate; 2) electron beam exposure: apply electron beam glue on the substrate, and use electron beam exposure equipment to expose A area, B area, and A area on the substrate. , area B has intersection area C; 3) developing: put the container that developer solution is housed in liquid, monitor the temperature of developer solution, when the temperature of developer solution reaches the planned temperature and maintains it stably at this temperature, put the developer solution Step 2) immerse the substrate obtained in the developing solution and shake it for development, and then fix it, so that the pattern formed by the electron beam glue is stabilized; 4) Twice oblique evaporation coating; 5) Metal peeling. The invention utilizes the electron beam exposure mask technology and the electron beam coating and metal stripping technology, and its technology is relatively simple, avoiding the complicated suspension gel preparation technology, and batch superconducting Josephson junction samples can be prepared within one day.