748results about How to "Molecular weight controllable" patented technology

The invention relates to a high-temperature resisting adhesive and a preparation method thereof; the adhesive is formed by the following ingredients: carboxyl contained polyimide resin powder, epoxide resin, curing agent and organic solvent with weight ratio of 1:10-20:0.1-2:20-30. The preparation method of the high-temperature resisting adhesive comprises the following steps: adding the carboxylcontained polyimide resin powder, the epoxide resin and the curing agent into a reaction kettle, heating the reaction kettle to 80-90 DEG C for carrying out stirring reaction for 0.5-1.5 hours, and then adding the organic solvent continuously, and stirring the mixture uniformly at room temperature, thus obtaining the high-temperature resisting adhesive. The preparation method has simple process and low cost and is environment-friendly, the preparation process can be carried out in a general device, thereby being suitable for industrial production.

The invention discloses a colorless and transparent aromatic polyimide film which has the general formula of molecular structure as follows; the preparation thereof includes: aromatic primary amine and aromatic acid anhydride with specific molecular structures are adopted for polymerization in a strong polar aprotic organic solvent system within the temperature range of 0 DEG C to 35 DEG C to prepare a colorless and transparent viscous polyamide acid solution with homogeneous phase. Viscosity adjustment, casting for forming the film, heating for rising temperature and solvent removal are carried out simultaneously when partial imidization reaction is carried out, and then demoulding and stretching, further deep thermal imidization and rolling are carried out to obtain the colorless and transparent aromatic polyimide film. No special production equipment is required by the invention so that production can be carried out on the conventional production line of the polyimide film and the polyimide film is applicable to industrialized production.

The invention relates to a preparation method of a star polycarboxylic acid high-performance water reducing agent. Polybasic alcohol and (methyl) acrylic acid used as main raw materials for esterification are esterified and polymerized to prepare the star polycarboxylic acid high-performance water reducing agent material: the (methyl) acrylic acid and polybasic alcohol used as reactants are esterified under the action of a catalyst to firstly prepare a star polymerizable active terminal, and free-radical polymerization reaction is carried out with unsaturated polyethenoxy ether, molecular weight regulator and unsaturated carboxylic acid monomer under the action of an initiator to prepare the star polycarboxylic acid high-performance water reducing agent. The invention is easy to control, and has the advantages of high polymerization degree, low cost and no pollution; the esterification reaction is carried out form an active core, and the free-radical polymerization is carried out to generate the chain arm, thereby implementing the polycarboxylic acid high-performance water reducing agent in a star molecular structure; and under the condition of common doping amount and low doping amount, the star polycarboxylic acid high-performance water reducing agent has better cement paste flowability and holding capacity than the traditional linear and comb polycarboxylic acid water reducing agents, and has favorable cement adaptability and concrete application performance.

The present invention discloses one kind of terminated non-ionic surfactant and its preparation process and application. The surfactant is allyl terminated polyether with molecular weight controllable in 700-9500 Da, narrow molecular weight distribution and high reaction activity. It has methylol terminating rate up to 95 % and double bond terminating rate up to 93 %, and possesses structure as shown.

The invention provides a block poly-carboxylic acid concrete high-efficiency water reducing agent with an ordered structure and a preparation method thereof. The block poly-carboxylic acid is prepared by using atom transfer radical polymerization, the structural regularity and the molecular weight distribution of the poly-carboxylic acid are controlled effectively, and the water reducing agent is used in a cement dispersing process. By adoption of the block poly-carboxylic acid concrete high-efficiency water reducing agent and the preparation method thereof, the problems of uncontrollable molecular weight of the poly-carboxylic acid, wider molecular weight distribution, un-designable molecular structure and the like are solved.

The invention discloses a synthesis method of a polycarboxylic acid high-performance water reducing agent of a star-like structure, belonging to the field of a water reducing agent. According to the synthesis method, polybasic alcohol, (methyl) acrylic acid, a polyethylene glycol compound and the like are used as esterification raw materials, and the polycarboxylic acid high-performance water reducing agent of the star-like structure is prepared through a sequential esterification and polymerization method, i.e., the (methyl) acrylic acid and the polybasic alcohol are used as reactants, a star-like polymerizable active end is prepared through esterification reaction under the action of a catalyst, and then the polycarboxylic acid high-performance water reducing agent is prepared from the star-like polymerizable active end and esterification macromolecule, a molecular weight regulator and an unsaturated carboxylic acid monomer under the action of an initiator through free radical polymerization reaction. The synthesis method has the advantages of simplicity, easiness in control, high polymerization degree, low cost, no pollution, capability of realizing the polycarboxylic acid high-performance water reducing agent of the star-like structure connected with a plurality of polycarboxylic acid molecules, and more superior cement paste fluidity and holding capacity, good cement adaptability and concrete application performance compared with the conventional linear and comb-shaped polycarboxylic acid water reducing agent in the case of normal and low added amount.

The invention relates to thermoplastic fluorine-containing fully aromatic polyimide powder, which has a general molecular structural formula shown above, wherein -R1 is a divalent linking group of fluorine-containing aromatic primary diamine; and -R2 is a divalent linking group of a molecule of aromatic acid dianhydride. The method comprises the following steps: reacting the fluorine-containing aromatic primary diamine with the aromatic acid dianhydride in a phenol solvent in the presence of a catalyst for 5 to 10 hours; pouring the hot solution in a precipitator with high-speed stirring to precipitate solid powder; and obtaining the thermoplastic fluorine-containing fully aromatic polyimide powder after filtration, washing, soaking, filtration and drying. The thermoplastic fluorine-containing fully aromatic polyimide powder has good solubility, is a high-performance heat-resistance toughness modifier for epoxy resin, unsaturated polyimide resin, unsaturated polyester resin and other thermosetting resins, and is good in application prospect, simple in operation, low in cost, environmentally-friendly, and suitable for industrial production.

A method of producing a healthcare yang-invigorating preparation for males is provided. The method is characterized in that: male silkworm pupa-cordyceps militaris-oyster peptides prepared by subjecting raw materials including male silkworm pupae, cordyceps militaris (L.) Link and oyster to enzymolysis, a composite extract prepared from mulberry fruit, barbary wolfberry fruit, palmleaf raspberry fruit, solomonseal rhizome, common yam rhizome, gordon euryale seed, poria, jujube kernels, cortex cinnamomi, Chinese date and ginseng and broken pine pollen prepared from pine pollen are added and fully mixed, an excipient is added into the mixture and the mixture is prepared into granules, capsules, and a tablet candy preparation according to conventional preparing processes. Compatibility of components adopted is scientific. An adopted preparing process is unique and simple. According to the method and the preparation, a production process is simple, the preparation is simple to eat, has effects of tonifying the kidney and qi, tonifying the lung and kidney, promoting sperm production, boosting marrow, invigorating the spleen and the stomach, improving microcirculation of human bodies, eliminating moisture, removing paralysis, boosting immunity, preventing fatigue, resisting viruses, strengthening bodies, invigorating yang and treating impotence, has obvious curative effects, mild functions and no side or toxic effects, and is an ideal healthcare yang-invigorating preparation for males.

The invention provides ABA type triblock biodegradable polyurethane with amino side chains and a preparation method and uses thereof, belongs to the field of biomedical materials and solves the problem that the existing biodegradable polyurethane has molecular weight uncontrollable, wide molecular distribution index and complexity in self-assembly. The ABA type triblock biodegradable polyurethane with amino side chains is shown as in a structural formula I or II. The ABA type triblock biodegradable polyurethane is controllable in polymer molecular weight and wide in molecular weight distribution and can serve as a drug carrier; drug molecules, target molecules or fluorescence molecules are grafted to active side groups of the polyurethane by means of physical encapsulation or chemical bonding, so that a carrier drug system having one or multiple of functions such as being untargeted, being targeted, pH sensitivity, photosensitivity, enzyme sensitivity and fluorescence probing is constructed.

The invention relates to a polymer mobility control agent suitable for an ultrahigh-salinity oil deposit and a preparation method thereof, and the polymer mobility control agent is mainly used for solving the problem that a polymer can not meet the requirement for tertiary oil recovery due to poor temperature resistant property, salt resistant property and shearing resistant property in the prior art. In order to better solve the problem, the technical scheme adopted by the invention is as follows: the control agent for an amphoteric hydrophobic associated polymer comprises the following components in parts by weight of the amphoteric hydrophobic associated polymer: 5-99.9 parts of nonionic water-soluble monomers, 0-50 parts of anionic monomers or / and cationic monomers, 0.1-10 parts of hydrophobic monomers with surface activity, 0.1-5 parts of inorganic substances and 1-20 parts of surface active agents. The preparation method disclosed by the invention can be used for the industrial production of the polymer mobility control agent suitable for the ultrahigh-salinity oil deposit.

The invention discloses a method for making 1, 4-double (2,4-diamino phenoxy) phenyl type self-toughening unsaturated polyimide powder. The method mainly comprises the following steps that: 1) 1, 4-double (2,4-diamino phenoxy) phenyl, aromatic series binary primary amine and aromatic series binary anhydride as well as an organic compound containing unsaturated double bond are stirred and react in a strong polar aprotic organic solvent system at a temperature of between 20 and 140 DEG C to obtain a brown and ropy thermoset polyamide acid solution capable of cross bonding and curing; 2) the obtained polyamide acid solution is dehydrated, mild-aminated, powdered, filtered, washed and dried to obtain the 1,4-double (2,4-diamino phenoxy) phenyl type self- toughening unsaturated polyimide powder.

The invention discloses an amphoteric heat-resistant and salt-resistant filtrate reducer for drilling fluid and a preparation method. The amphoteric heat-resistant and salt-resistant filtrate reducer is prepared from, by weight parts, acrylamide, alkenyl sulfoacid or alkenyl sulphonate, acrylic acid, cationic monomers, rigid monomers, sodium hydroxide, potassium hydroxide, dispersant, deionized water, a molecular weight modifier and an initiator. The preparation method includes the steps that acrylamide, acrylic acid, alkenyl sulfoacid or alkenyl sulphonate, the cationic monomers, the rigid monomers and the deionized water are added into a reactor, after the materials are dissolved, the pH value of the solution is adjusted, the dispersant is added, the materials are mixed, then the mixture is transferred into a reaction still, nitrogen is introduced for deoxygenization, the initiator is added for triggering polymerization, and jelly is taken out after the reaction is completed, dried, smashed and sieved. The molecular weight of the filtrate reducer for the drilling fluid is controllable; the filtrate reducer can adapt to complex drilling conditions, and can be used in horizontal wells, high-temperature deep wells and evaporite beds; fewer residual monomers of the filtrate reducer for the drilling fluid are generated; the filtrate reducer and other oil field chemicals are good in compatibility; the preparation method is simple; the cost is low, and popularization is promoted.

The invention discloses a process for synthesis of polysiloxane which comprises the steps of charging reactant, catalyst and water, agitating at normal temperature, reacting in the microwave reaction field for 60-120 min, and charging terminating substance, the constituents include (by weight portions) reactant 100 parts, catalyst 0.01-0.05 part, water 0.01-0.1 part, and terminating substance 0.01-0.1 part.

The invention relates to a preparation method of a high-temperature resistant polyimide glass fabric laminated board, which comprises the following steps: (1) adding 1,4-bis(2,4-diaminophenoxy) benzene and maleic anhydride to a non-proton organic solvent with strong polarity, then adding aromatic diamine monomer, aromatic dibasic anhydride and initiator, and stirring for dissolving to obtain a component A; (2) adding 1,4-bis(2,4-diaminophenoxy) benzene and maleic anhydride to a non-proton organic solvent with strong polarity, stirring and reacting for 2 hours to obtain a component B; and (3) mixing the component A and the component B evenly to obtain a polyimide precursor resin solution, impregnating the glass fabric in the resin solution, and obtaining the high-temperature resistant polyimide glass fabric laminated board after preliminary drying semi-curing and high-temperature press thermo-curing. The high-temperature resistant polyimide glass fabric laminated board prepared in the invention has excellent heat resistance, can be applied to high-temperature resistant electro-insulating material and high-temperature resistant structural part material of aerospace vehicles, and has wide application prospects.

The invention discloses a degradable polylactic acid diblock copolymer, a preparation method and application to modified polylactic acid, solving the problems of instable performance, high preparation cost and unsuitability for industrialized continuous production of modified polylactic resin in the prior art. The preparation method of the degradable polylactic acid diblock copolymer comprises the following steps of: adding dried and dewatered polylactic acid A with an end group being hydroxy into a reaction device under the protection of an inert atmosphere, adding diisocyanate B, heating to 185-190 DEG C, reacting with stirring for 5-8h, adding degradable high polymer C containing hydroxy, reacting with stirring for 1-2h at the temperature of 185-190 DEG C, adding the diisocyanate B, and reacting at the temperature of 185-190 DEG C until the stirring is difficult to obtain the degradable polylactic acid diblock copolymer. The degradable polylactic acid diblock copolymer disclosed by the invention is good in compatibility with the polylactic resin, is used for modifying the polylactic resin, is capable of remarkably improving processing property and mechanical property of the polylactic resin, and has the elongation at break reaching 60 percent.

The invention provides a method for preparing ester terminated allyl alcohol polyether, which has simple process and realizes diversity of ester terminated allyl alcohol polyether monomer structure. The method for preparing the ester terminated allyl alcohol polyether comprises the following steps: allyl alkyl acid ester is used as initiator and ternary metal oxide is used as catalyst to ensure that oxirane and / or propylene epoxide perform a ring-opening polymerization reaction at 100-140 DEG C under the pressure of 0.1 to 0.6MPa; the ester terminated allyl alcohol polyether can be obtained after the catalyst is filtered and removed, wherein the ternary metal oxide catalyst is prepared from soluble salt of Mg, Al and Ca through alkaline precipitation and calcination. The preparation process is simple without using organic solvent, can be completed in one step by continuously adding materials in the same reactor. The prepared ester terminated allyl alcohol polyether monomer molecule has diverse structures, adjustable amphipathic property and controllable molecular weight, and can be polymerized with multiple unsaturated monomers.

The invention discloses a carbonate polymer with a disulfur five-membered ring functional group on a side chain and an application thereof. The polymer is obtained by active ring opening polymerization from a cyclic carbonate monomer containing the disulfur five-membered ring functional group; the polymer is controllable in molecular weight, narrower in weight molecular distribution and free from protecting and deprotecting process. The polymer obtained by active ring opening polymerization of the cyclic carbonate monomer has biodegradability and can be used for controlling a drug release system; a reduction-sensitive reversible crosslinking nano medicine carrier targeting tumor supports long circulation in vivo but is highly enriched in tumor cells and is quickly crosslinked to release medicine in cells so as to efficiently kill the tumor cells with specificity. Meanwhile, the carbonate polymer has an application prospect in aspects such as tissue engineering scaffolds and biochip coatings and the like.

The invention belongs to a method for preparing small molecular weight or water-solubility chitosan by using radiation process. It is characterized by that a refined high molecular weight chitosan solid or solution can be irradiated by using 60 Co gamma-rays and degraded, and the degradation product is undergone the after-treatment steps of dissolution and decolouration, etc. so as to obtain the invented small molecular weight or water-solubility chitosan. Said chitosan has several purposes, can be used as agricultural production-increasing agent, food drying agent, natural anti-bacterial material and bio-medicine material, etc.

The invention relates to a polymer mobility control agent suitable for a high-temperature and high-salinity harsh reservoir and a preparation method of the polymer mobility control agent, and the polymer mobility control agent is mainly used for solving the problems that the polymer in the prior art is poor in heat and salt resistance and long-term stability, and cannot meet the requirements of tertiary oil recovery. In order to better solve the problems, the technical scheme adopted by the invention is as follows: an amphoteric hydrophobic association polymer is prepared from the following raw materials in parts by weight: 5-99.9 parts of a non-ionic water-soluble monomer, 0-50 parts of an anionic monomer or / and cationic monomer, 0.1-10 parts of a hydrophobic monomer with surface activity, 0-20 parts of a viscosity stabilizer and 0-20 parts of a surfactant. The preparation method can be applied to industrial production and application of the polymer mobility control agent for the high-temperature and high-salinity harsh reservoir.

This invention discloses a self-drying low aliphatic chain oxosilane modified water-borne acrylic resin and preparation method thereof. The water-borne acrylic resin is prepared by adding a solvent into (methyl) acrylate monomers, styrene monomers, vinyl versatate monomers, low aliphatic chain oxosilane monomers, initiators and chain transfer agents to form mixed solution, and then carrying out polymerization reaction on the mixed solution. The preparation method is characterized in that a novel normal temperature self-drying water-dispersed resin is obtained by carrying out solution polymerization and using the low aliphatic chain oxosilane monomers, and simultaneously by carrying out polymerization and carrying out hydrolysis and cross-linking on the modified acrylic resin. In addition, the resin obtained by selecting the non-toxic or low-toxicity solvent and then carrying out solution polymerization through an one-pot method has the characteristics of environmental friendliness, low cost, good water resistance and high hardness, and the like, and can be used for producing normal temperature curing water-borne paint.

The invention relates to a fluorine-containing imine matrix resin used for advanced composite material, which comprises the following components: 1wt%-15wt% of fluorine-containing polyimide low polymer powder, 5wt%-20wt% of fluorine-containing active polyimide powder, 60wt%-70wt% of multifunctional epoxy resin and 5wt%-20wt% of curing agent; the preparation method comprises the steps of feeding fluorine-containing diamine monomer, fluorine-free diamine monomer and strong-polar aprotic organic solvent, adding aromatic dianhydride solid powder, stirring and reacting at room temperature, adding a dehydrating agent and a catalyst, heating and reacting for 3 hours, adding a precipitant to precipitate out solid powder, cooling to room temperature, filtering, washing and drying, thus obtaining the fluorine-containing polyimide low polymer powder; preparing the fluorine-containing active polyimide powder in a same way; leading the two materials and the multifunctional epoxy resin to conduct bulk polymerization reaction, and then adding the curing agent after dissolution. The method has simple process, low cost and environmental protection effect, can finish the preparation process in standard equipment, and is applicable to industrial production.

The invention relates to the field of nano technology and discloses a method for preparing SiO2-PDMAEMA nanoparticles having a core-shell structure. The method comprises the following steps of: selecting 2-bromideisobutyryl bromide with a higher initiation activity or a compound represented by a formula (I) as an initiator by using an atom-transfer radical-polymerization method; and during reaction, mixing CuX2 serving as a passivator, a ligand, SiO2 nanoparticles modified by the initiator, a solvent and diethylaminoethyl methacrylate at first and then adding CuX to perform a grafting reaction to obtain the SiO2-PDMAEMA nanoparticles with the core-shell structure. Experiments show that: the prepared SiO2-PDMAEMA nanoparticles have the advantages of controllable particle size, narrow particle size distribution and controllable molecular weight of the polymer PDMAEMA grafted on the surface of SiO2. Moreover, the preparation method provided by the invention has the characteristics of mild reaction conditions, convenience, feasibility and short preparation period and is easy for mass production.

The invention discloses vegetable oil modified rosin phenolic resin and a preparation method thereof. Alkyl phenol reacts with formaldehyde under an alkaline condition to obtain an alkyl phenol resin condensation compound; molten rosin and vegetable oil are firstly used to conduct a Diels-Alder addition reaction; then the alkyl phenol resin condensation compound is dripped into a reaction product of the molten rosin and the vegetable oil to conduct a Diels-Alder addition reaction; and finally, after a final reaction product is esterified, the vegetable oil modified rosin phenolic resin is prepared. The preparation method has the advantages that through the Diels-Alder reaction of the rosin and the vegetable oil, an aliphatic chain is led to a molecular structure, so that the solubility of the rosin phenolic resin in mineral oil is effectively improved, and a softening point of the resin is guaranteed at the same time; the n-heptane accommodation degree is larger than or equal to 20mL / 2g and the acid value is smaller than or equal to 25mgKOH / g, so that the vegetable oil modified rosin phenolic resin can serve as matrix resin of heat-set ink and satisfies the requirements of fast drying, high gloss, demulsibility, and the like of the heat-set ink.

The invention relates to an oil displacing system for increasing oil recovery in high temperature high salt mid-low permeability oil reservoir, and a preparation method thereof, and aims to solve the problems that in the prior art, hydrophobic associated polymer can easily obstruct the holes of sandstone formation, the injection performance of oil displacing agent is bad in the immediate vicinity of wellbore, the oil displacing agent can only applied to mid-high permeability oil reservoirs, and the hydrophobic associated polymer can easily react with oil displacing surfactant to generate chromatographic separation. The oil displacing agent comprises the following components in parts by weight: 0.01 to 1 part of adsorption resisting agent, 0.05 to 3 parts of hydrophobic associated polymer, 0.2 to 5 parts of oil displacing surfactant, and 91 to 99.8 parts of water; wherein the adsorption resisting agent is one or more of nonionic surfactant and anionic surfactant. The provided oil displacing agent well solves the problems mentioned above, and can be applied to the onsite oil displacing in a mid-low permeability oil reservoir.

The invention discloses a method for synthesizing linear high molecular weight polyphenylene sulfide and belongs to the technical field of chemical material. The method comprises the following steps: by taking sodium sulphide and dichloro diphenyl as raw materials, synthesizing the linear high molecular weight polyphenylene sulfide (PPP) resin through a solution polycondensation method and a secondary polymerization process in a compound solvent and a cosolvent system. The method is simple in process and convenient to operate; the product has a high molecular weight linear structure; in the whole polymerization process, the molecular weight is controllable. Compared with the prior art, the method has the advantages of good solvent system dissolving property, low salt content and easy separation. The monomer reactivity of the linear polymerization reaction is high and the chain extension is easy to process. The dosage of the alkali metal or the alkaline earth chloride is few and the metal ion can be easily washed. The linear high molecular weight polyphenylene sulfide does not have irritant or carcinogenic property and is environmentally friendly to operate.

The invention discloses a low-temperature-resisting crude silicon rubber which is obtained by polymerizing octamethyl cyclotetrasiloxane (D4), hexaethylcyclotrisiloxane (D3Et), 2,4,6,8-tetravinyl-2,4,6,8-tetramethylcyclotetrasiloxane (D4Vi), a catalyst and an accelerating agent and then heating, removing small molecular low-boiling-point substances in materials in vacuum and cooling to room temperature. According to the invention, the low-temperature-resisting crude silicon rubber product disclosed by the invention is stable, the glass transition temperature (Tg) of the rubber is low and is not crystallized at low temperature; polymerization process is simple and does not need a solvent, and the high-molecular-weight low-temperature-resisting crude silicon rubber can be obtained through severely controlling reaction conditions in short reaction time; and the rubber is high in yield, controllable in molecular weight, simple in posttreatment and easy to produce in a large scale.

The invention provides a fluorine-containing waterproofing agent for textiles and a method for preparing the same, belonging to the chemical material field. A self-emulsifying fluorine-containing acrylate block copolymer is synthesized by means of ARGETATRP (Activators Regenerated by Electron Transfer for Atom Transfer Radical Polymerization); and the self-emulsifying fluorine-containing acrylate block copolymer can be directly used after being emulsified and diluted. The self-emulsifying fluorine-containing acrylate block copolymer prepared by the method has excellent pH stability, chemical stability, diluting stability and storage stability; and the fluorine-containing structure units are distributed in form of blocks on the polymeric chain of the fluorine-containing acrylate block copolymer so that the fluorine-containing chain segments can be effectively utilized. Compared with a random fluorocarbon resin, the fluorine-containing acrylate block copolymer is capable of achieving the same performance and the usable amount of fluorine-containing monomers is very low. Moreover, textiles finished by the fluorine-containing waterproofing agent have excellent waterproofness; and compared with the similar products, the fluorine efficiency is improved and the cost is reduced.

The invention discloses a method for preparing a carbon-coated lithium titanate negative electrode material for a lithium battery. The method comprises the following steps: preparing a polymer with controllable molecular weight by adopting living polymerization, performing ball milling and mixing with raw materials of lithium titanate, and sintering to obtain a lithium titanate material coated with a conductive carbon layer. The adopted polymerization method has the advantages that range of optional monomers is wide, polymers of different carbon chain lengths can be obtained by adjusting the raw material ratio, the carbon chain length distribution is uniform, and the finally obtained carbon-coated lithium titanate material is uniform and stable in performance. Moreover, the initial charge specific capacity of the obtained lithium titanate material reaches over 160mAh / g under the rate of 1C (1C=175mA / g), and the capacity is kept over 90 percent due to cycle of 800 times.

The invention relates to a preparation method of functionalized ultra-high molecular weight polyethylene resin. In the method, a modifying additive is added to solvent oil, and with ethylene as a raw material and under the effects of a catalyst and hydrogen, a low-pressure slurry method is employed to prepare the functionalized ultra-high molecular weight polyethylene resin. The method, compared with the prior art, is simple and is suitable for large-scale production. The resin is controllable in molecular weight and has uniform distribution in molecular weight. The modifying additive in the resin is uniformly mixed.

The invention discloses a high-molecular weight long-chain branched crystalline polylactic acid material and a preparation method thereof. The preparation method comprises the following steps of: 1) adding 0.1 to 1 percent of protonic acid catalyst into aqueous solution of lactic acid or mixed solution of the aqueous solution of the lactic acid and silicon dioxide nano particle silica sol containing 0.1 to 10 weight percent of lactic acid, and dehydrating to obtain a product I; 2) adding 0.4 to 2 molar percent of dibasic acid or anhydride into the product I, and reacting to obtain a product II; 3) adding 0.1 to 1 weight percent of lewis acid catalyst into the product II, performing melt polycondensation, and adding 0.1 to 5 weight percent of crystallization accelerator to obtain terminal carboxyl group crystalline polylactic acid prepolymers; and 4) reacting diglycidyl ester and the terminal carboxyl group crystalline polylactic acid prepolymers in a molar ratio of 0.8:1-1.2:1 to obtain the high-molecular weight long-chain branched crystalline polylactic acid material. The preparation method has the advantages of simplicity, short reaction time, high efficiency, low cost and environmental friendliness and capability of contributing to realizing commercialization.