47results about How to "Strong steric hindrance" patented technology

The invention relates to a polyester resin used for TGIC curing high-toughness thermal transfer printing powder paints, and a preparation method thereof. The glass-transition temperature of the polyester resin is relatively high, so that prepared powder paint coating possesses high toughness at normal temperature and -15 DEG C. According to the preparation method, the polyester resin is obtained via melt polycondensation of following raw materials: a polyol, a polyacid, an acidolysis agent, an esterification catalyst, an antioxidant, and a curing accelerator. The preparation method comprises following steps: 1) the polyol is delivered into a reaction kettle at a needed ratio, rapid heating esterification is carried out, water is generated, and is removed via distillation; 2) temperature is increased gradually, and an obtained material is maintained to be clear; 3) sample examination is carried out; 4) one half of the antioxidant is added, and negative pressure polycondensation is carried out; and 5) cooling is carried out, one half of the antioxidant and the curing accelerator are added, stirring dispersing is carried out, and an obtained product is cooled, and is collected.

The invention discloses zero-VOC (volatile organic compound) cement-based water-proof material copolymer emulsion and a preparation method thereof. The preparation method adopts a zero-VOC copolymer emulsion component A and an inorganic powder component B, the zero-VOC copolymer emulsion component A is prepared from deionized water, alkyl acrylate, styrene, acrylic acid functional monomers, emulsifying agents, initiators, a buffer agents, polymerization inhibitors, oxidizing agents, reducing agents, sterilizing agents and defoaming agents through polymerization of pre-emulsification semi-continuous seed emulsion, and the inorganic powder component B comprises ordinary portland cement, quartz sand and water reducers. The prepared emulsion is high in solid content, low in viscosity, uniformin particle size and good in stability and has excellent rheological property and coating water absorption, the content of a residual monomer in an emulsion product is lower than 300ppm and meets national zero-VOC emulsion standards, the emulsion is environmentally friendly and free from toxicity and pollution, the compatibility of the emulsion and cement is good, and a prepared polymer cement waterproof coating is excellent in water resistance, good in low-temperature flexibility and low in water absorption.

The invention discloses slow-release collapse-preventing type polycarboxylic water reducing agent and a preparation method thereof, and belongs to the field of preparation of the water reducing agent. The slow-release collapse-preventing type polycarboxylic water reducing agent consists of methyl allyl polyoxyethylene ether, acrylic acid, methyl acrylic polyethylene glycol monoester, imide, initiator, vitamin C, chain transfer agent and deionized water. The preparation method comprises the following steps of: preparing macromonomer methyl allyl polyoxyethylene ether, acrylic acid, methyl acrylic polyethylene glycol monoester, imide and vitamin C; under the action of the polymerization initiator and the chain transfer agent, dissolving the methyl allyl polyoxyethylene ether into deionized water, rising temperature to 40 DEG C for dissolving, adding the initiator, then respectively dripping water solution A prepared by dissolving the chain transfer agent, the acrylic acid, the methyl acrylic polyethylene glycol monoester and the imide in the deionized water and V.C water solution B, and after the dripping is finished, carrying out insulation, cooling and neutralization to obtain a finished product. The slow-release collapse-preventing type polycarboxylic water reducing agent disclosed by the invention has the advantages that the loss and the evaporation of water in concrete due to long-time transportation and higher temperature are effectively prevented, and the difficulty of excessively-fast slump loss of the concrete in engineering is solved.

The invention relates to a method for synthesizing dihydroxypropyl bisphenol A ether through a one-step process, and belongs to the technical field of organic compound synthesis. The method comprises the steps of: by taking bisphenol A as the raw material, orderly carrying out material melting and synthesis by adding a chain extension agent, and finally obtaining the dihydroxypropyl bisphenol A ether, wherein the hydroxyl value of the dihydroxypropyl bisphenol A ether is 325-330mgKOH/g, and the color of the dihydroxypropyl bisphenol A ether is smaller than No.30. The technical scheme of the method is used for synthesizing the product through the one-step process, and the problems of complex preparation process, many process steps, high energy consumption, high composite cost, poor product quality and so on in the conventional technology are solved; the obtained product is rational in distribution, low in product color; and the content of the by-product allyl alcohol matters is low.

The invention relates to a dispersing agent for a fluorescent brightener, a fluorescent brightener aqueous dispersion, a preparation method of the dispersing agent, as well as a preparation method and application of the fluorescent brightener aqueous dispersion. The preparation method of the dispersing agent comprises the following steps: firstly, separately dissolving acrylamide and an allyl polyoxyethylene ether monomer of which the polymerization degree is 23 in a proper amount of deionized water; then, controlling the temperature to be 79-81 DEG C under the stirring condition, separately adding the allyl polyoxyethylene ether monomer aqueous solution and an ammonium persulfate initiating agent into a four-mouth flask filled with a certain amount of deionized water drop by drop within 2-3 hours, and carrying out 3-4 hours' heat preservation after the drop-by-drop adding is finished; finally, carrying out cooling to prepare the dispersing agent of which the weight-average molecular weight is 10000-20000. The invention further provides the fluorescent brightener aqueous dispersion which contains the fluorescent brightener OB-1, the prepared dispersing agent and deionized water. When the fluorescent brightener aqueous dispersion is applied to whitening of a fabric, the fabric can be whitened and brightened very uniformly, and the whitening effect is obvious.

The invention provides polycarboxylic acid, use thereof and a water reducer containing the same, belongs to the technical field of cement additives and solves the problems of low water reduction rate and slump keeping performance of the conventional water reducer. The polycarboxylic acid is an irregular copolymer formed by polymerization of 50 to 80 weight percent of unsaturated polyether of a general formula below, 15 to 30 weight percent of unsaturated carboxylate or unsaturated carboxylate and 0 to 25 weight percent of third monomer which has unsaturated double bonds and polar groups, wherein R1 and R2 represent hydrogen atom or methyl; R3 and R5 represent oxyalkylene; R4 and R6 represent hydrogen atoms or C1 to C20 alkyl; a and c are integers between o and 3; b and d are 0 or 1; and m and n are integers between 10 to 50. The water reducer provided by the invention consists of 40 to 60 weight percent of polycarboxylic acid and the balance of water. The invention also discloses the use of the polycarboxylic acid in water reducer. The water reducer can be used high-strength concrete.

The invention discloses mono-carboxyl chitosan/alkannin composite nanometer particles and a preparation method thereof. Alkannin coated nanometer particles are prepared through ion gel coagulation effects of water-soluble mono-carboxyl chitosan and sodium tripolyphosphate, and then mutual cross-linking and assembling of hydrophilic macromolecule addition agents and the mono-carboxyl chitosan, composite nanometer particle being small in particle diameter, homogeneous in size, high in stability and good in biological activity are prepared. The method disclosed by the invention is simple and easyto operate, low in cost, mild in reaction condition, environmentally-friendly, safe and non-toxic, the obtained composite nanometer particles are resistant to gastric acid and high in stability, andthe orally-taken absorption and utilization rate of a Chinese herbal medicine namely alkannin and the target medicine release properties are effectively improved.

The invention belongs to the technical field of dispersing agent preparation, and discloses a comb polyelectrolyte type dispersing agent with dispersed nano particles and a preparation method of the dispersing agent. The dispersing agent comprises 3-(2-methacryloyloxyethyl trimethyl dimethylamino) propanesulfonic acid salt, enol polyoxyethylene ether, a chain transfer agent, an initiator, a chain terminator and deionized water. The prepared dispersing agent disclosed by the invention is comb polyamphoteric electrolyte; and after the nano particles adsorb the dispersing agent disclosed by the invention, steric hindrance effect among nano particles is relatively strong, and sedimentation is hardly caused. Therefore, the dispersing effect is good. Meanwhile, quaternary ammonium salt cation is introduced into a macromolecule main chain, so that the hydratability and the heat stability of the dispersing agent are enhanced.

The invention discloses a polylactic acid/ MWCNT (multi-walled carbon nanotube) sensitive material with low percolation threshold and low limit of detection and an application of the polylactic acid/ MWCNT sensitive material. The sensitive material is a homogenously dispersed body prepared from high-molecular-weight polylactic acid as a matrix and MWCNTs as a conductive current carrier through stirring and compounding at 40-50 DEG C with a simple and low-cost solution mixing technology, wherein polylactic acid accounts for 95.0wt%-97.5wt%, and the MWCNTs account for 2.5wt%-5.0wt%. Due to the strong steric hindrance action of high-molecular-weight polylactic acid and the good self-organization action of the high-molecular-weight polylactic acid on the surfaces of the CNTs, the sensitive material has good dispersibility, and the percolation threshold is as low as 2.9wt%; a composite film sensing element with smooth surface can be assembled conveniently from the sensitive material and is applied to chloroform vapor detection, the sensitive material has higher response intensity, rapid response and recovery performance and good repeatability and stability, and the limit of detection of chloroform vapor is as low as 10 ppm. The sensitive material can be taken as a novel gas sensor for rapid detection of indoor and outdoor environmental gas.

The invention discloses a heat-insulating fireproof decorative plate and relates to the field of decoration. The decorative plate comprises a plate body, which is coated with a heat-insulating fireproof layer. Raw materials of the heat-insulating fireproof layer comprise the following ingredients (by weight): 25-30 parts of an acrylate emulsion adhesive, 3-5 parts of nano-aluminium hydroxide, 4-6parts of ammonium polyphosphate, and 2-4 parts of hollow glass beads. The invention has the following advantages: the heat-insulating fireproof system formed by the above ingredients has excellent fireproof and sound-insulation properties.

The invention discloses a chitosan oligosaccharide graft modified polycarboxylic acid water reducing agent and a preparation method of the water reducing agent. The method comprises the following steps: 1) preparing a chitosan oligosaccharide amidated macro-monomer, placing chitosan oligosaccharide and maleic anhydride in a molar ratio of 1:1.02-1.1 into a polar solvent, adding a catalyst at 85-95DEG C and carrying out a reaction for 3-4 h under stirring, and performing washing and oven-drying to obtain the powdery chitosan oligosaccharide amidated macro-monomer; and 2) preparing the water reducing agent, performing free radical polymerization in an aqueous solution on methyl allyl polyoxyethylene ether and the chitosan oligosaccharide amidated macro-monomer to obtain the chitosan oligosaccharide graft modified polycarboxylic acid water reducing agent. The chitosan oligosaccharide amidated macro-monomer directly participates in polymerization through a carbon-carbon double bond, and has high polymerization activity, and chitosan oligosaccharide side chains can greatly enhance viscosity-increasing water-retention properties of the water reducing agent, and can further enhance dispersion of the water reducing agent. In addition, the chitosan oligosaccharide side chains interacts with polyether long side chains, so that a hydrated film formed on the surface of cement particles ismore stable, and slump-loss is smaller over time.

The invention belongs to the field of precious metal metallurgy, in particular to a benenficiation reagent and a using method of separating and recycling precious metal from copper anode mud. According to weight proportion, the beneficiation reagent is composed of 1-10 parts by weight of collector pinitol xanthate and pinitol aerofloat, 1-10 parts by weight of inhibitor sodium, namely, hexametaphosphate and 1-10 parts by weight of foaming agent, namely, pinitol oil. The method of separating and recycling precious metal is that first of all, acid leaching pretreatment is performed, then acid leaching residue is prepared into slurry, the slurry is added with the beneficiation reagent and rough selection is performed, then two accurate selections are performed, and precious metal ores are acquired. The benericiation reagent and the using method of separating and recycling precious metal from cooper anode mud is strong in selectivity of the beneficiation reagent, high in precious metal separating efficiency, and high in recycling rate of gold and silver, and capable of reducing cost and pollution.

The invention provides a polyurethane dispersant as well as a preparation method and application thereof, and relates to the technical field of dispersants. The preparation method provided by the invention comprises the following steps: mixing polypropylene glycol, 2,2-dimethylolpropionic acid, aromatic isocyanate and an organic tin catalyst, and carrying out a first polymerization reaction to obtain a prepolymer; mixing the prepolymer with a ketone solution of 1,4-butanediol, and carrying out a second polymerization reaction to obtain a chain extension polymer; mixing the chain extension polymer with polyethylene glycol, and carrying out polycondensation reaction to obtain a polycondensate; mixing the polycondensate with a neutralizer, and carrying out neutralization reaction to obtain apolycondensate solution; and mixing the polycondensate solution with water, and emulsifying to obtain the polyurethane dispersant. By adopting the polyurethane dispersant prepared by the invention, the storage stability of a pesticide water suspending agent can be remarkably improved.

The invention relates to a method for preparing a bio-base high-efficiency delayed-coagulation water-reducing agent from natural chitin. The method comprises the following steps: degrading a natural high polymer, and carrying out functional group remolding, so as to obtain a chitosan oligosaccharide intermediate containing functional groups such as amino and hydroxymethyl; carrying out condensation reaction by virtue of phenol and formaldehyde under alkaline conditions so as to generate a phenolic aldehyde intermediate, and carrying out addition reaction by virtue of sodium hydrogen sulfite and formaldehyde so as to introduce hydrophilic sulfonic acid groups to the phenolic aldehyde intermediate; and linking the chitosan oligosaccharide intermediate with the sulfonated phenolic aldehyde intermediate by virtue of hydroxymethyl polycondensation, so as to obtain the bio-base high-efficiency delayed-coagulation water-reducing agent with good water-reducing and delayed-coagulation effects. The chitin bio-base high-efficiency delayed-coagulation water-reducing agent has the characteristics of low raw material cost, environment-friendly protection process and the like and further has relatively good water-reducing and delayed-coagulation effects. The chitin bio-base high-efficiency delayed-coagulation water-reducing agent has economic and environmental protection benefits and is a novel high-efficiency water-reducing agent with great promise.

The invention discloses a compound containing a triarylamine structure, and an organic light-emitting device prepared from the same. The pi conjugation effect in the compound enables the compound to have a very strong hole transport capability, and the high hole transport rate can reduce the initial voltage of the device and improve the efficiency of the organic light-emitting device; the asymmetric triarylamine structure can reduce the crystallinity of molecules, reduce the planarity of the molecules and prevent the molecules from moving on a plane, so that the thermal stability of the molecules is improved; the structure of the compound makes distribution of electrons and holes in a light-emitting layer balanced, and improves the hole injection and transport performances under a proper HOMO energy level; the structure also has an electron blocking layer under a proper LUMO energy level, so the recombination efficiency of excitons in the light-emitting layer is improved; and when thecompound is used as a hole transport layer or an electron blocking layer material of the OLED luminescent device, the triarylamine is matched with the branched chain in the structure, so the exciton utilization rate and the radiation efficiency can be effectively improved.

The invention provides an early strengthening polycarboxylate superplasticizer for C30 concrete and a preparation method. The polycarboxylate superplasticizer is prepared from the following ingredients in parts by weight: 342 to 353 parts of polyether macromonomers with the molecular weight being 4000 to 4500, 22 to 27 parts of acrylic acid, 4 to 8 parts of rigid small monomers, 2 to 5 parts of 27.5-percent industrialized hydrogen peroxide, 3.5 to 6 parts of unsaturated sulfonate, 2 to 4 parts of functional phosphate monomers, 0.4 to 0.6 part of reducing agents, 1.4 to 2.4 parts of chain expanding agents, 6 to 12 parts of neutralizers and the balance water. The total mass is 100 parts. After the preparation, the mass percentage of the finished product is 40 percent; the acid-ether ratio control range is 3.9 to 4.3. The used polyether macromonomers are prepared from amidogen ether and polyether through being proportioned according to the mass ratio of 1:6; amino groups are reasonably introduced; slight soluble gypsum is promoted to be completely dissolved into water; the hydration process of C3A is accelerated; the formation of ettringite is promoted; the early strengthening effect is achieved.

The invention relates to the technical field of anticorrosive paint, and in particular relates to water-based epoxy anticorrosive paint for containers as well as a preparation method and application thereof. According to the water-based epoxy resin modified by blending organosilicon in the anticorrosive paint, hydroxyl of the organosilicon and epoxy of the epoxy resin are subjected to ring-opening reaction so as to form stable Si-0-C bonds; and meanwhile, the internal stress of the system is reduced by utilizing a coupling agent, so that the compatibility of the system is improved. The mechanical properties and chemical resistance of the epoxy resin are improved. The water-based epoxy anticorrosive paint uses a high-molecular dispersing agent, and relatively strong steric hindrance and good dispersion stability are generated through the group adsorption effect of a high-molecular-weight main chain and the anchoring effect of a high-molecular polymer containing an anchoring group on the chain of the high-molecular-weight main chain; the wetting dispersity of the pigment and filler in an emulsion is improved, and the problems of pigment and filler precipitation, remarkable viscosity change and the like are solved after long-time storage.