45results about How to "The synthesis method is stable" patented technology

The invention relates to a method for preparing a polycarboxylate superplasticizer by carrying out graft copolymerization on acrylic ester polymer and fatty acid vinyl ester. According to the method for preparing the polycarboxylate superplasticizer by carrying out graft copolymerization on the acrylic ester polymer and fatty acid vinyl ester, acrylic ester polymer and fatty acid vinyl ester are taken as main reaction raw materials, polymerization is carried out firstly, then grafting is carried out and then alcoholysis and hydrolysis are carried out to prepare the polycarboxylate superplasticizer grafted and polymerized with the acrylic polymer and fatty acid vinyl ester, namely acrylic ester is taken as a reaction monomer, polymerization is carried out under the actions of an initiating agent and a molecular weight regulating agent, then graft polymerization is carried out with the fatty acid vinyl ester to obtain a graft copolymer with the acrylic ester polymer as a main chain and polyvinyl ester fatty acid as a side chain, and finally alcoholysis and hydrolysis are carried out on the graft copolymer. The method for preparing the polycarboxylate superplasticizer by carrying out graft copolymerization on the acrylic ester polymer and fatty acid vinyl ester has the advantages that a process is simple and easy to control, cost is low, environmental protection is realized, no pollution is produced, the fatty acid vinyl ester is used for replacing the existing polycarboxylate superplasticizer, and diversification of raw materials is enriched; and the prepared superplasticizer has good cement paste fluidity and holding capability and shows good cement adaptability and concrete application property.

The invention relates to a method for synthesizing a cement dispersing agent by using a terminated functional polyethylene fatty acid ester macromonomer. The cement dispersing agent is prepared by taking fatty acid vinyl ester as a main reaction raw material through a method comprising the steps of autopolymerization, substitution, alcoholysis and copolymerization, namely, polymerizing by taking fatty acid vinyl ester as a reaction monomer under the action of an initiator and a chain transfer agent to generate a polymer; then, carrying out substitution reaction on the polymer and an unsaturated chlorinated substance to obtain a polyethylene fatty acid ester macromonomer of which the macromolecular chain terminal is a double bond; next, carrying out alcoholysis on the macromonomer to prepare a macromonomer with the double bond at the terminal and with a polyvinyl alcohol structure; and finally, carrying out copolymerization reaction on the macromonomer and a carboxylic acid micromonomer to prepare the cement dispersing agent. The method is simple and easily-controlled in process, low in cost, environment-friendly and pollution-free; and the cement dispersing agent prepared by taking fatty acid vinyl ester as the raw material has favorable net cement paste flowability and holding capacity and shows favorable cement adaptability and concrete application property.

The invention discloses a europium-based coordination polymer nanosphere and a preparation method and application thereof. The preparation method of the europium-based coordination polymer nanosphere comprises the following steps of adding EuCl3.6H2O, H2BDC and polyvinylpyrrolidone to mixed solvent formed by mixing N, N-dimethylformamide and absolute ethyl alcohol, and conducting stirring till the materials are fully dissolved; then, transferring a mixed solution into a reaction still provided with a polytetrafluoroethylene inner container, and putting the reaction still in a drying oven at the temperature of 150 DEG C to leave the reaction still standing still for 12 hours; and then sequentially conducting cooling, centrifugalization, washing and vacuum drying, so that the europium-based coordination polymer nanospheres are obtained. A to-be-detected water body is added to fluorescent material suspension liquid prepared from the europium-based coordination polymer nanospheres; after being mixed uniformly, the materials are left standing still; and then a fluorescence spectrophotometer is adopted for detection, and the content of phosphate in the to-be-detected water body can be obtained. The europium-based coordination polymer nanosphere is stable in performance, not prone to photobleaching, good in water solubility, capable of effectively detecting the content of the phosphate in the water body, simple in synthesis method and low in raw material cost.

The invention relates to a method for preparing mannose-containing derivatives capable of being used for post-polymerization modification by double-click chemistry combination. The method comprises the following steps: under the actions of propargyl bromide and acryloyl chloride respectively, preparing a compound with terminal alkyne and terminal olefin by using a Williessen ether-forming reaction; and then performing sulfydryl-alkene addition reaction on terminal olefin and sulfydryl compounds, and performing CuAAC reaction on terminal alkyne and acetyl-protected alpha-D-pyranomannose azide.Compared with the prior art, mercaptan substances with different structures are successfully combined with the alpha-D-pyranomannose azide through a mercapto-alkene addition reaction and GuAAC combined method for the first time, the mannose-containing derivative capable of being applied to post-polymerization modification is prepared, and the synthesis method is stable, efficient and high in yield. A considerable way is provided for obtaining a sugar-containing homopolymer with controllable molecular weight and narrower molecular weight distribution in the later period.

The invention provides a preparation method of a phosphate ester or a phosphite ester. The preparation method comprises the following step: reacting an inorganic phosphate or an inorganic phosphite with a silicon-substituted cycl-lactam compound shown in a formula 3) to obtain the phosphate ester shown in a formula 1) or the phosphite ester shown in a formula 2). The preparation method provided bythe invention not only can be used for preparing phosphate esters, but also can be used for preparing phosphite esters. The synthetic method disclosed by the invention is mild and stable in reaction,convenient to operate, high in yield, high in purity and low in energy consumption in the reaction process, and is a universal synthetic method for synthesizing phosphate esters or phosphite esters.

The invention discloses a preparation method and application of hydrophobic graphene aerogel. The invention belongs to the field of graphene aerogel. The problems that an existing hydrophobic grapheneaerogel material is high in preparation cost, poor in structural strength and the like can be solved. A hydrothermal reaction method is adopted, a saccharide cross-linking agent which is low in priceand easy to obtain is adopted, an organic auxiliary agent and efficient and cheap modifiers such as trimethylchlorosilane are added, and the hydrophobic and oleophylic graphene aerogel material is obtained through a normal-pressure drying method and a microwave annealing method. It can be seen through scanning electron microscope imaging that the material is structurally a thin-wall porous material formed by three-dimensional crosslinking of thin-layer graphene. The material is definite in synthesis process, short in synthesis time, low in cost, free of heavy metal and organic pollutants, high in structural strength and capable of bearing the heavy pressure which is more than one hundred times of the mass of the material. The material has super-hydrophobicity, and the contact angle measured by experiments is as high as 150 degrees or above. The hydrophobic graphene aerogel can be used in the fields of protection and removal of volatile organic compounds in air and water, and other oil-water separation applications.

The invention discloses a method for preparing a glycopolymer through combination of ROMP polymerization and a mercapto-alkene addition reaction. The method uses a gradient organic synthesis method, combines a thiol-ene Michael addition, and prepares a norbornene derivative of a heterosaccharide monomer containing non-protective group, and the glycopolymer with controllable molecular weight and narrow molecular weight distribution width can be obtained through ring-opening metathesis polymerization (ROMP). Based on the advantage of thiol-ene Michael addition, a feasible platform and an approach are provided for preparing the heterosaccharide monomer with an ordered side-chain structure; and the heterogeneous glycopolymer prepared by an active ROMP polymerization has important guidance meaning for researching a specific identification mechanism of a sugar unit and agglutinin as well as for developing the functional glycopolymer having a special biological diagnosis function.

The invention relates to a method for preparing an MOF / carbon composite material under the assistance of atomic layer deposition, an obtained product and application. The preparation method comprises the steps of preparing metal oxide / carbon composite materials with different thicknesses; and preparing the MOF / carbon composite material. The MOF / carbon composite material is prepared by taking a carbon material as a substrate and combining atomic layer deposition and an organic solution and metal matching experiment. The method is simple in process, meanwhile, the number of MOFs can be accurately controlled, the defects of MOF agglomeration and different particle sizes are effectively overcome, and the method has wide application value in the fields of energy storage, electromagnetic wave absorption, heat conduction and the like.

The invention relates to a surfactant, and provides a biquaternary ammonium salt surfactant. A chemical name of the biquaternary ammonium salt surfactant is biquaternary ammonium salt dibromo N,N-bis(long-chain alkyl dimethyl)-3-oxa-1,5-pentanediamine. A synthetic method of the biquaternary ammonium salt surfactant comprises the following steps: (1) adding 0.1 mol of diethylamine into a three-necked flask with a stirrer and 2 dropping funnels, then respectively adding 0.05mol of dichloroethane and 0.05mol of sodium hydroxide solution with a weight / volume percent of 40 percent, and preparing tetraethylethylenediamine; and (2) adding bromododecane, tetraethylethylenediamine and absolute ethyl alcohol into the three-necked flask with a reflux condensation apparatus, recrystallizing, separating and purifying to obtain the biquaternary ammonium salt surfactant. By adopting the biquaternary ammonium salt surfactant, the problem that the biquaternary ammonium salt surfactant for producing a polyester fabric is uneasy to synthesize can be solved.

The invention belongs to the technical fields of polymer materials technologies and harmful gas treatment, and particularly relates to an aminooxy structure-containing polymer and a formaldehyde adsorbent including the polymer, and preparation methods thereof. Reversible addition-fragmentation chain transfer (RAFT) polymerization or atom transfer radical polymerization (ATRP) is used to obtain thepolymer containing a large amount of aminooxy groups, the polymer and a two-dimensional carrier material are commonly loaded on porous melamine foam or polyurethane foam to prepare an aerogel material, and the aerogel material is a three-dimensional material capable of efficiently adsorbing gaseous formaldehyde, that is, the formaldehyde adsorbent. The formaldehyde adsorbent in the invention realizes reversible chemical adsorption of the formaldehyde gas at normal temperature under normal pressure in the absence of a catalyst, combines the high specific surface area of the carrier and the three-dimensional porous structure of the foam, and can be used for specifically and efficiently adsorbing the gaseous formaldehyde; and the formaldehyde can be desorbed under the action of dilute hydrochloric acid, so the formaldehyde adsorbent can be repeatedly used.

The invention discloses the preparation of a cyclo-metalated iridium-azo complex and an application of the cyclo-metalated iridium-azo complex to the detection of sulfur dioxide. The complex provided by the invention can react with the sulfur dioxide specifically to produce the fluorescent response, has strong cell membrane penetration capacity and low cytotoxicity, can be used for identifying the sulfur dioxide in the cells and has a great application potential in the aspect of real-time and quick detection of the sulfur dioxide.

The invention relates to a preparation method and application of a calcium hydroxide-loaded graphene aerogel composite material, belongs to the technical field of graphene aerogel, and can solve the problems of limited absorption amount and complex production process of an existing industrial harmful gas treatment and absorption method, and the preparation method adopts a step-by-step synthesis method and comprises the following steps: firstly, synthesizing calcium hydroxide particles by utilizing a precipitation method; and synthesizing graphene oxide by using an electrolytic oxidation method. In the next step, calcium hydroxide and graphene oxide are subjected to a polymerization reaction through a hydrothermal synthesis method, and finally the graphene aerogel composite material loadedwith calcium hydroxide is obtained. The composite material can be used in the field of chemical adsorption removal of acidic industrial harmful gases such as SO2, H2S, Cl2 and the like, and can also be used in the field of adsorption of VOCs gases such as benzene and the like.

The invention discloses a synthesis method of diclofenac sodium, which comprises the following steps: (1) dropwise adding chloroacetyl chloride into toluene, aniline and a catalyst solution while stirring, carrying out heat preservation reflux, then adding 2, 6-dichlorophenol and sodium carbonate, carrying out heat preservation reflux, extracting with water to obtain an oil layer, adding alkali into the oil layer, and carrying out heat preservation reaction to obtain 2, 6-dichlorodiphenylamine; (2) heating and melting the 2, 6-dichlorodiphenylamine prepared in the step (1), dropwise adding chloroacetyl chloride, heating, carrying out heat preservation reaction, hydrolyzing, and crystallizing to obtain N-(2, 6-dichlorophenyl)-phenyl-chloroacetamide; (3) carrying out heating reaction on the N-(2, 6-dichlorophenyl)-phenyl-chloroacetamide prepared in the step (2) and aluminum trichloride, and carrying out pumping to obtain solid 1-(2, 6-dichlorophenyl)-2-indolinone; and (4) adding the 1-(2, 6-dichlorophenyl)-2-indolinone prepared in the step (3) into alkali liquor, stirring, heating and refluxing to obtain the diclofenac sodium. The synthesis method is stable, easy to operate, low in cost, high in yield and suitable for industrial production.

The invention belongs to the technical field of advanced nano materials, and particularly relates to a magnetic nanorod with an ordered large mesoporous polymer shell layer and a synthesis method of the magnetic nanorod. The synthesis method comprises the following steps of: by taking magnetic nano-particles as seeds, depositing a silicon dioxide layer on the surfaces of the particles through a sol-gel method and a magnetic field auxiliary assembly method, and then directionally arranging and assembling under the induction of a stable magnetic field to form a one-dimensional rod core; depositing a macromolecular surfactant / high molecular layer composite material on the surface of the one-dimensional rod core by adopting interface co-assembly and using a high-molecular-weight block copolymer as a template agent; and removing the surfactant to form a one-dimensional ordered large mesoporous polymer-based material layer with an ordered mesostructure on the surface of silicon dioxide. The nanorod has an ordered large mesoporous channel, a stable structure, a controllable mesostructure, a strong hydrophilic surface, unique magnetic anisotropy of a one-dimensional magnetic material and spontaneous shearing and stirring performance. The preparation method is simple, the yield of the method is high, synthesis raw materials are easy to obtain, and the nanorod is suitable for large-scale production.

The invention relates to a method for preparing mesoporous nano ferroferric oxide particles from titanium dioxide byproduct ferrous sulfate, and belongs to the technical field of inorganic functionalmaterial and electrochemical energy. The method is capable of solving a problem that synthesis cost of electrode mesoporous nano ferroferric oxide particles is high. The method comprises following steps: firstly, respectively dissolving a ferric salt and an alkaline carbon-containing compound in deionized water, uniformly mixing two obtained solutions, pouring an obtained mixed solution into a beaker, blowing oxygen into the beaker, and sealing; and at last, carrying out low-temperature heating reaction. The key points are that in the ferroferric oxide nucleation-crystallization process, CO2generated by a carbon-containing compound is used as a template to form ferroferric oxide nanoparticles with large specific surface area and adjustable size. According to the method, the cheap titanium dioxide byproduct ferrous sulfate is utilized, the use of various expensive additives is avoided, the method is suitable for large-scale production, and when the obtained Fe3O4 nanoparticle materialwith the large specific surface area is used for iron-nickel batteries and super capacitors, the capacity is remarkably improved, and the method has great economic benefits.

The invention discloses a preparation method of a cation-modified molybdenum oxide or tungsten oxide nanowire with a large specific surface area. The preparation method comprises the following steps of: dissolving inorganic cations and a molybdenum source or tungsten source in deionized water, stirring solution, simultaneously regulating the pH value of the solution to be above an isoelectric point of molybdenum oxide or tungsten oxide by using protonic acid, then transferring into a self-pressure reaction kettle, reacting for 1-30 hours at a constant temperature of 100-240 DEG C after sealing, separating out solid products after the reaction is ended, washing, and drying to obtain the cation-modified molybdenum oxide or tungsten oxide nanowire with the large specific surface area. The cation-modified molybdenum oxide or tungsten oxide nanowire has the characteristics that the diameter is small, the distribution is narrow (3-10nm), the length-diameter ratio is more than 250, the porouseffect is achieved, the specific surface area is not smaller than 200m<2> / g, the degree of crystallinity is lower and the surface hydroxyl groups are rich and the like.

The invention discloses a phenylboronic acid functionalized Ti3C2Tx magnetic composite material and a preparation method and application thereof. The phenylboronic acid functionalized Ti3C2Tx magnetic composite material is prepared by modifying Ti3C2Tx with a multi-layer structure into amino Ti3C2Tx, namely Ti3C2Tx-NH2, then synthesizing Ti3C2Tx-CTFs-NH2 through further hyperbranched reaction of melamine and cyanuric chloride, and carrying out covalent crosslinking on 4-formyl phenylboronic acid through acetal to synthesize boric acid functionalized Ti3C2Tx, namely Ti3C2Tx-BA; and finally dispersing Fe3O4 nano particles in the surface and interlayer structure of Ti3C2Tx-BA to prepare the phenylboronic acid functionalized Ti3C2Tx magnetic composite material, namely Fe3O4@Ti3C2Tx-BA. The phenylboronic acid functionalized Ti3C2Tx magnetic composite material has the advantages of high adsorption capacity, good selectivity, stable structure, simple and convenient synthesis method, low preparation cost, strong regeneration capability, strong anti-interference capability, short extraction time and the like. The preparation method has the advantages of rapidness, high efficiency, low cost, environmental friendliness, reusability and the like.

The invention relates to a preparation method of a sericite-doped expandable polystyrene composite bead. According to the method, by a method of increasing viscosity in advance, in-situ polymerization is conducted on a styrene monomer or a certain amount of polystyrene, ABS (Acrylonitrile Butadiene Styrene) resin or polymethyl methacrylate are added into the styrene monomer, after the viscosity of the styrene phase is increased, a dispersing agent solution is added for suspension polymerization, and the sericite-doped polystyrene beads are obtained. The process for preparing the sericite-doped expandable polystyrene composite beads by using an early viscosity increasing method is stable, the phenomenon of sticking to a kettle is avoided, polystyrene waste can be utilized in the preparation process, and the preparation of diversified and multifunctional polystyrene beads can be realized.

The invention discloses a norbornene derivative based homopolymer containing heterogeneous sugar units and a synthetic method of the homopolymer. With the adoption of a gradient organic synthesis method, an acetyl protected norbornene monomer NB-Man-Glu-OAc containing heterogeneous sugars is prepared by combining with a copper catalyzed azido-terminal alkyne [3+2] cycloaddition reaction (CuAAC), then a linear sugar-containing homopolymer with controllable molecular weight and narrower molecular weight distribution is obtained with ROMP (ring-opening metathesis polymerization), and the final homopolymer PNB-Man-Glu-OH containing the heterogeneous sugar units is obtained by deprotection. One simple and efficient path is provided for synthesis of sugar-containing polymers which contain the heterogeneous sugar units, and synthesis of the sugar-containing polymers has great guiding significance in studying special recognition mechanism for the sugar units and lectin and developing functional sugar-containing polymers with special biological diagnosis functions.

The invention relates to a method for synthesizing a cement dispersing agent by using a terminated functional polyethylene fatty acid ester macromonomer. The cement dispersing agent is prepared by taking fatty acid vinyl ester as a main reaction raw material through a method comprising the steps of autopolymerization, substitution, alcoholysis and copolymerization, namely, polymerizing by taking fatty acid vinyl ester as a reaction monomer under the action of an initiator and a chain transfer agent to generate a polymer; then, carrying out substitution reaction on the polymer and an unsaturated chlorinated substance to obtain a polyethylene fatty acid ester macromonomer of which the macromolecular chain terminal is a double bond; next, carrying out alcoholysis on the macromonomer to prepare a macromonomer with the double bond at the terminal and with a polyvinyl alcohol structure; and finally, carrying out copolymerization reaction on the macromonomer and a carboxylic acid micromonomer to prepare the cement dispersing agent. The method is simple and easily-controlled in process, low in cost, environment-friendly and pollution-free; and the cement dispersing agent prepared by taking fatty acid vinyl ester as the raw material has favorable net cement paste flowability and holding capacity and shows favorable cement adaptability and concrete application property.

The invention discloses a method for preparing a sugar-containing polymer by combining affinic ROMP polymerization and mercapto-ene addition reaction. The present invention utilizes the gradient organic synthesis method, combined with the thiol-ene Michael Addition reaction (Thiol-ene Michael Addition), to prepare norbornene derivatives containing non-protecting groups of heterosaccharide monomers, followed by ring-opening metathesis polymerization ( ROMP) to obtain sugar-containing homopolymers with controlled molecular weight and narrow molecular weight distribution width. Based on the advantages of mercapto-ene addition reaction, the present invention provides a feasible platform and approach for preparing heterogeneous sugar-containing monomers with ordered side chain structures; The specific recognition mechanism of units and lectins and the development of functional sugar-containing polymers with special biodiagnostic functions have important guiding significance.

The invention discloses the preparation of a cyclo-metalated iridium-azo complex and an application of the cyclo-metalated iridium-azo complex to the detection of physiological thiol. The complex provided by the invention can react with the physiological thiol specifically to produce the fluorescent response, has strong cell membrane penetration capacity and low cytotoxicity, can be used for identifying the thiol in the cells and has a great application potential in the aspect of real-time and quick detection of the physiological thiol.

The invention discloses a europium-based coordination polymer nanosphere and a preparation method and application thereof. The preparation method of the europium-based coordination polymer nanosphere comprises the following steps of adding EuCl3.6H2O, H2BDC and polyvinylpyrrolidone to mixed solvent formed by mixing N, N-dimethylformamide and absolute ethyl alcohol, and conducting stirring till the materials are fully dissolved; then, transferring a mixed solution into a reaction still provided with a polytetrafluoroethylene inner container, and putting the reaction still in a drying oven at the temperature of 150 DEG C to leave the reaction still standing still for 12 hours; and then sequentially conducting cooling, centrifugalization, washing and vacuum drying, so that the europium-based coordination polymer nanospheres are obtained. A to-be-detected water body is added to fluorescent material suspension liquid prepared from the europium-based coordination polymer nanospheres; after being mixed uniformly, the materials are left standing still; and then a fluorescence spectrophotometer is adopted for detection, and the content of phosphate in the to-be-detected water body can be obtained. The europium-based coordination polymer nanosphere is stable in performance, not prone to photobleaching, good in water solubility, capable of effectively detecting the content of the phosphate in the water body, simple in synthesis method and low in raw material cost.

The invention relates to a method for preparing a mannose-containing derivative that can be used for post-polymerization modification by combining double click chemistry. First, under the action of propargyl bromide and acryloyl chloride, respectively, a Williamson-forming ether is used to prepare a mannose-containing derivative. Compounds with terminal alkynes and terminal alkenes. Then, the terminal alkene and the mercapto compound undergo a mercapto-ene addition reaction, and the terminal alkyne and the acetyl-protected α-D-mannopyranosyl azide undergo a CuAAC reaction. Compared with the prior art, the present invention successfully combines thiol substances of different structures with α-D-mannopyranosyl azide through the combined method of mercapto-ene addition reaction and GuAAC to prepare A mannose-containing derivative that can be used for post-polymerization modification is developed. The synthesis method is stable and efficient, and provides a considerable way for obtaining sugar-containing homopolymers with controllable molecular weight and narrow molecular weight distribution in the later stage.

The invention relates to the technical field of synthesis of two-armed sugar-containing compounds, in particular to a two-armed heterogeneous sugar-containing compound and a preparation method thereof. The preparation method comprises the following steps: firstly, enabling external norbornene anhydride to react with 4-bromoaniline, replacing oxygen in the external norbornene anhydride with amino, then forming a biphenyl compound by utilizing Suzuki reaction, then reacting with isopropylidene-2, 2-bis (oxymethyl) propionic anhydride by utilizing esterification reaction, and introducing dihydroxyl under an acidic condition through deprotection; then carrying out esterification reaction and pentyne anhydride reaction to obtain a dialkyne compound; and carrying out a CuAAC reaction with nitrine sugar to prepare the double-arm heterogeneous sugar-containing compound. Compared with the prior art, the method has the advantages that the two-arm terminal alkyne-containing compound is synthesized by utilizing the advantages of the Suzuki reaction, and the method has important guiding significance on later preparation of sugar-containing monomers with different functions and research on the influence of isosaccharide in a two-arm sugar-containing polymer on the specific recognition effect of protein.

The invention relates to the technical field of synthesis of amino acid-containing saccharide derivatives, in particular to a cysteine-containing saccharide derivative and a preparation method thereof. The preparation method comprises the following steps: firstly, preparing a compound with terminal alkyne and terminal olefin, carrying out Thiol-ene reaction on the terminal olefin and N-acetylcysteine methyl ester, and carrying out CuAAC reaction on the terminal alkyne and acetyl-protected alpha-D-mannopyranose azide to prepare the cysteine-containing saccharide derivative. Compared with the prior art, cysteine and alpha-D-mannopyranosyl azide are successfully combined through a click chemical reaction for the first time, and the amino acid-containing saccharide monomer which can be used for RAFT polymerization and post-polymerization modification is prepared. And a considerable way is provided for obtaining the homopolymer with controllable molecular weight and narrower distribution in the later stage.

The invention provides a synthesis method of o-cresol formaldehyde epoxy resin, which comprises steps that: at 0.01-0.1MPa vacuum degree, the o-cresol formaldehyde epoxy resin is dissolved by epichlorohydrin and a catalyzer is added for circumfluence and etherification reaction; at the 0.02-0.1MPa vacuum degree, alkali is added for catalyzing cyclization reaction; the epichlorohydrin is recycled and processed after refining reaction. The o-cresol formaldehyde epoxy resin obtained by the synthesis method of the invention can reach a scheduled softening point and has high epoxy value and low content of easily saponifiable chlorine.

The invention relates to a preparation method of a pH responsive polycarboxylic acid of a comb-shaped structure. The preparation method comprises the following steps: by taking acrylate and a pH responsive monomer as raw materials, preparing a polycarboxylic acid material by self-polymerization and graft copolymerization and hydrolysis: by taking acrylate as a reaction monomer, carrying out polymerization under the action of an initiator and a chain transfer agent to generate polyacrylate with controllable molecular weight and then copolymerizing with the pH responsive monomer to obtain a grafted copolymer taking the polyacrylate polymer as a main chain and the pH responsive polymer as a side chain; and finally, hydrolyzing the grafted copolymer to prepare the polycarboxylic acid of the comb-shaped structure taking polyacrylic acid as the main chain and the pH responsive polymer as the side chain. The preparation method is mild in condition and energy-saving and efficient. By introducing the pH responsive polymer by means of a molecular structural design, the polycarboxylic acid with a special functional side chain is synthesized, so that a pH responsive behavior is achieved successfully. The polycarboxylic acid shows an excellent characteristic of inhibiting shrinkage of cement mortar and has a wide market prospect and a popularizing and applying potential.