778results about How to "High molecular weight" patented technology

The invention discloses an adhesive, lithium battery negative electrode slurry, a lithium battery negative electrode and a lithium battery. The adhesive comprises an acrylic copolymer; polymeric monomers of the acrylic copolymer comprise an acrylic monomer, an acrylonitrile monomer, an acrylamide monomer and a selective acrylate monomer; the preparation method of the acrylic acid copolymer comprises the following steps: mixing an acrylic acid monomer with water, adding alkali for neutralization until the neutralization degree is greater than or equal to 50% and less than 100%, then adding an acrylamide monomer and an acrylonitrile monomer, selectively adding an acrylic ester monomer, heating to a reaction temperature in a protective atmosphere, and carrying out a reaction for 2-4 hours to obtain the acrylic acid copolymer. Adding an initiator to initiate an aqueous solution polymerization reaction to generate an acrylic copolymer; practice shows that the binder has higher molecular weight and better electrical performance, when the binder is applied to the negative electrode of the lithium battery, excellent binding power and battery cycle performance can be obtained while the use amount of the binder is reduced, and the binder can be used for preparing the lithium battery, related electrodes and the like.

The invention discloses a multifunctional water-retaining agent adapted to acid soil and a preparation method thereof, and the multifunctional water-retaining agent is prepared from the following raw materials in parts by weight: 9-11 parts of a chitosan solution with the concentration of 0.019-0.021 g / mL, 9-11 parts of a sodium polyphosphate solution with the mass concentration of 0.5-1%, 24-25 parts of an acrylic acid solution with the neutralization degree of 80-85%, 9-11 parts of a guar gum solution with the concentration of 0.019-0.021 g / mL and the balance of water. The mass of the methylene bisacrylamide accounts for 0.01-0.03% of the total dry matter mass of the chitosan, the guar gum and the acrylic acid, the mass of the ammonium persulfate accounts for 0.25-0.35% of the total dry matter mass of the chitosan, the guar gum and the acrylic acid, and the clay mineral accounts for 10-12 parts; the preparation method comprises the following steps: S1, pre-preparation; S2, mixing; and S3, post-treatment. The prepared water-retaining agent not only can greatly improve the water absorption and water retention performance of the chitosan water-retaining agent, but also can reduce the acidity of acid soil and improve the CEC and fertilizer retention capacity of the soil, and is a multifunctional acid red and yellow soil conditioner.

The invention provides a robot joint dynamic cable made of a self-repairing polyurethane material and a preparation method of the robot joint dynamic cable, and belongs to the field of cables. Polytetrahydrofuran glycol and hexamethylene diisocyanate react to form a soft and hard segment structure, 1, 4-butanediol is added for chain extension, dopamine hydrochloride is introduced, the hard segment structure is enhanced, and a self-repairing hydrogen bond network is formed; carbon nanotubes are introduced, and through plasma treatment and silane coupling agent modification, the tensile resistance, fatigue resistance and electrical properties of the material are improved; montmorillonite is compounded with polyethyleneimine through organic treatment, so that the cracking resistance and wear resistance of the material are enhanced; epoxy groups are introduced to the surface of boron nitride, and dopamine hydrochloride is self-polymerized, so that excellent heat dissipation capability and dimensional stability are provided. Through the synergistic effect of the components, the composite material has excellent mechanical properties, electrical properties, heat dissipation, wear resistance and the like, is especially suitable for a dynamic cable of a robot, and can stably work in a complex environment for a long time.

The invention belongs to the field of polymeric membranes. The invention relates to a BOPLA (biaxially-oriented polylactic acid) film with high stretching ratio and a preparation method thereof. The packaging film comprises the following raw materials in parts by weight: 80-90 parts of PLA; 10 to 20 parts of PPC-P (Polypropylene Chloride-P); 10-15 parts of a plasticizer; 3.0 to 5.0 parts of a chain extender; 0.3 to 0.5 part of an antioxidant; 0.5 to 1.0 part of a lubricant; 0.1 to 0.3 part of an anti-hydrolysis agent; wherein the total mass of the PLA and the PPC-P is 100 parts; the preparation method comprises the following steps: mixing, extruding and plasticizing the raw materials according to the formula, and carrying out an asynchronous two-way stretching process, heat setting, traction, slitting and rolling. According to the present invention, the defects of mechanical property degradation and poor optical property of the PLA under the high stretching rate in the prior art can be effectively solved, and the great application potential is provided.

The invention provides BiTE for tumor targeted immunotherapy and a preparation method and application, and relates to the technical field of biological pharmacy, the BiTE is obtained by coupling a nano antibody and fusion protein, the C terminal of the nano antibody contains an amino acid sequence SEQ ID No.3, and the BiTE has the function of targeting a human epidermal growth factor receptor on tumor cells; the fusion protein also targets a CD3 receptor on a T cell, activates the T cell, connects the T cell with a tumor cell in time and space, activates the T cell, secretes perforin and granzyme B to kill the tumor cell, and plays a role in targeted immunotherapy. The isopeptide bond is used for coupling the nano antibody and the fusion protein, coupling can be completed within 15 min, the coupling efficiency is 100%, and the in-vivo half-life period of the nano antibody can be prolonged by 6 times.

The invention belongs to the technical field of biomedicine, and particularly relates to a nano antibody aiming at influenza A virus H1N1 subtype NA protein and application. The nano antibody comprises an amino acid sequence as shown in SEQ ID NO: 1 or consists of the amino acid sequence as shown in SEQ ID NO: 1. The nano antibody has high affinity, and experimental results show that the antibody can effectively inhibit proliferation of PR8 H1N1 virus in vivo and resist infection of lethal dose virus on mice. Meanwhile, the nano antibody is the first nano antibody which aims at the N1 subtype NA protein and has prevention and treatment effects, the market blank is filled, and the nano antibody can be applied to the fields of laboratory research, biosensor development, clinical diagnosis, infection prevention and treatment and the like. The nano antibody provided by the invention has the advantages of small molecular weight, high stability, low production cost and the like, and has wider application potential and market competitive advantages compared with the traditional IgG antibody.

The invention belongs to the technical field of high polymer materials, and particularly relates to spinning-grade all-aryl polynaphthyl ester resin and a preparation method thereof. According to the invention, p-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, aromatic dicarboxylic acid and ethylene glycol monomer are adopted as raw materials, polymerization reaction is carried out under the action of the catalyst, spinning-grade all-aryl polynaphthyl ester resin is successfully obtained under specific reaction conditions, and the spinning-grade all-aryl polynaphthyl ester resin has high molecular weight, low impurity content and good heat resistance, and can be used for preparing the spinning-grade all-aryl polynaphthyl ester resin. The melt fluidity is good, the shear thinning phenomenon is more obvious, and the method can be directly used for preparing the polynaphthalene ester fiber.

The invention discloses a diabetes type enteral nutrition preparation composition capable of adjusting osmotic pressure, which comprises the following components in parts by weight: 30-60 parts of carbohydrate, 10-40 parts of fat powder, 15-40 parts of protein, 0-10 parts of dietary fiber, 0.1-10 parts of composite mineral, 0.1-2 parts of composite vitamin and 0-1 part of chelating agent. According to the technical scheme, the osmotic pressure is reduced by additionally adding the chelating agent aiming at sufficient fortified mineral salt in the diabetes type enteral nutrition preparation. The chelating agent added into the enteral nutrition preparation can be chelated with free mineral salt metal ions in the brewing liquid to form a chelating structure with larger molecular weight, so that the osmotic pressure of the instant product is reduced, and the osmotic pressure is adjusted in a reasonable range through the matching of other components and the change of the addition amount of the chelating agent.

The invention provides a modified porous chitosan gel bead, a preparation method thereof and application of the modified porous chitosan gel bead in cobalt-nickel separation, and belongs to the technical field of chitosan preparation. The preparation method comprises the following steps: firstly, modifying chitosan by using polyethylene glycol and glutaraldehyde to obtain a porous chitosan gel bead with a cross-linked structure, and then grafting by using epichlorohydrin, ethylenediamine and 2-chloromethylpyridine hydrochloride to obtain the modified porous chitosan gel bead containing an aminomethylpyridine functional group. The modified porous chitosan gel bead has excellent selective adsorption on nickel ions in a cobalt-nickel solution with the pH value range of 2-5, and nickel-cobalt separation can be achieved. In addition, the modified porous chitosan gel bead also has a good nickel-cobalt separation effect in a salt-containing system. The preparation method of the modified porous chitosan gel bead provided by the invention is simple in process, and the raw material chitosan is wide in source, non-toxic and environment-friendly.

According to the method, a one-pot copolymerization method is adopted, MBAA and borax serve as cross-linking agents, zwitterionic polyelectrolyte hydrogel containing SBMA, PVA, THMA and AMPS is prepared, and the zwitterionic polyelectrolyte hydrogel has excellent adhesion performance and biocompatibility and is suitable for the field of biological medicine. According to the method, the physical characteristics of the hydrogel are enhanced due to crosslinking sites and hydrogen bonds of polyvinyl alcohol. The cationic and anionic groups of SBMA improve the adhesion performance, and the reaction monomer THMA provides hydrogen-bond interaction to further promote adhesion, so that the prepared hydrogel adhesive shows excellent adhesion performance and biocompatibility, and is suitable for biological medicine application of wound dressing, drug release systems, tissue engineering and the like.

The invention relates to the technical field of cationic polymers, in particular to a high-alkali-resistance polyarylene alkylene piperidine cationic polymer with a branched structure as well as a preparation method and application of the high-alkali-resistance polyarylene alkylene piperidine cationic polymer with the branched structure, and the high-alkali-resistance polyarylene alkylene piperidine cationic polymer comprises one or more of a central unit, a linear unit L1 and a linear unit L2, the central unit comprises one or more of an MA unit, a piperidine cation unit m-DMP and a CA unit, the linear unit L1 comprises the piperidine cation unit m-DMP and a BA unit, and the linear unit L2 comprises a BA unit and a CA unit. By adopting the steps, the interaction force between polymer molecular chains is enhanced and the polymer molecular weight is increased through a branching strategy, so that the water absorption swelling of the prepared anion exchange membrane is inhibited, and the anion exchange membrane shows outstanding conductivity and mechanical properties; meanwhile, piperidine cations are linked to a polymer skeleton with a branched structure through a flexible spacer, so that the prepared anion exchange membrane has outstanding alkali resistance.

The invention provides a construction method and application of a high-efficiency expression system based on a Seali forest virus replicon. The method comprises the following steps: constructing a saRNA system for expressing a reporter gene; constructing to obtain replicase providing plasmids in the taRNA system; constructing to obtain an antigen providing plasmid in the taRNA system; the method comprises the following steps: respectively linearizing pSFV-CMV-T7-X, pSFV-CMV-T7-TR-X and pSFV-CMV-T7-replicase, and then carrying out in vitro transcription to prepare mRNA (Messenger Ribonucleic Acid); transfecting the prepared mRNA into a host eukaryotic cell for expression according to a certain proportion to obtain an antigen protein; and detecting the antigen protein to evaluate the expression efficiency of the saRNA and taRNA system based on the SFV replicon. According to the self-amplification DNA and RNA vaccine based on the virus replicon, the development period can be shortened, and the vaccine antigen can be expressed at a high level.

The invention is suitable for the technical field of chemical industry, and provides a method for preparing polycarbonate diol by using a titanate catalyst, which comprises the following steps: step 1, transesterification: mixing dimethyl carbonate and 1, 6-hexanediol according to a molar ratio of 1.1-1.5: 1, adding isopropyl titanate which accounts for 0.01-2% of the total raw material amount as a catalyst, and reacting at the temperature of 50-60 DEG C for 1-3 hours; carrying out transesterification on the mixture; step 2, carrying out condensation polymerization to obtain a polycarbonate diol crude product; and step 3, carrying out reduced pressure purification, and removing the small molecular polymer and the residual titanium isopropoxide catalyst to obtain the high-purity polycarbonate diol. According to the present invention, the efficient titanium isopropoxide catalyst is used under the normal pressure, such that the preparation of the high-purity and narrow-molecular-weight-distribution polycarbonate diol is achieved, the operation condition is mild, the production efficiency is high, the cost is low, and the catalyst has characteristics of low boiling point, easy removal and environmental protection.

The invention provides a suspension polymerization method for preparing polyvinylidene fluoride and application thereof, and the method comprises the following steps: polymerizing polyvinylidene fluoride in a polymerization reactor containing a dispersant, an initiator system, at least one chain transfer agent and water to form a polyvinylidene fluoride suspension; the initiator system comprises at least one first initiator and at least one second initiator, the first initiator being selected from one or more of the following: a peroxide C2-C12 carboxylic acid ester, a peroxide C2-C12 carboxylic acid, a persulfate, a C2-C10 alkyl peroxide, a C2-C12 acyl peroxide; the second initiator is a peroxide carbonate. Polyvinylidene fluoride prepared by the suspension polymerization method has higher molecular weight, higher melting point and wider molecular weight distribution, not only has excellent mechanical property, but also has good processability, wider use temperature range, good corrosion resistance and permeation resistance, excellent heat resistance and ageing resistance, and can be used for preparing the polyvinylidene fluoride material. The method is suitable for preparing the lining layer of the marine dynamic flexible riser.

The invention provides a micro-fluidic chip and a preparation method and application thereof, and belongs to the field of in vitro diagnose.The micro-fluidic chip comprises aptamer magnetic beads, a reactor and multivalent DNA nanowire reaction liquid, the aptamer magnetic beads comprise aptamer magnetic beads labeled by biotinylated staphylococcus aureus aptamers and aptamer magnetic beads labeled by biotinylated escherichia coli aptamers; the aptamer magnetic beads comprise aptamer magnetic beads labeled by biotinylated staphylococcus aureus aptamers and aptamer magnetic beads labeled by biotinylated escherichia coli aptamers; the reactor comprises two sample micro-chambers, two magnetic suction chambers, two snakelike mixing channels, two detection chambers and a sample outlet; the multivalent DNA nanowire reaction solution is a mixed solution comprising a multivalent DNA nanowire, heme and Tris-HCl. The micro-fluidic chip provided by the invention has the advantages of high sensitivity, strong specificity, low cost and simplicity in operation.

The invention relates to the field of phenolic resin adhesives, and particularly discloses a preparation method of a phenolic resin adhesive for a bamboo oriented strand board, which comprises the following steps: (1) phenol activation: adding phenol and a basic catalyst aqueous solution into a reaction kettle, and activating to form an intermediate state of phenate negative ions; (2) addition stage: adding a high-concentration formaldehyde reactant into the reaction kettle, and carrying out heat preservation reaction to generate hydroxymethyl phenol; (3) heating and replenishing: heating to 80 + / -2 DEG C, keeping the temperature, replenishing the formaldehyde aqueous solution into the reaction kettle, and keeping the temperature for 20-25 minutes; (4) polycondensation stage: adding a basic catalyst aqueous solution, heating to 90 + / -2 DEG C, and carrying out heat preservation reaction; and (5) terminating the reaction: after the heat preservation reaction, detecting the viscosity, cooling, and discharging to obtain the adhesive. The phenolic resin with the solid content of 60% or above can be prepared, the adhesive has excellent bonding performance, and the prepared shaving board is excellent in mechanical strength.

The invention discloses an acrylate finishing emulsion and a preparation method thereof, and the acrylate finishing emulsion comprises the following components in parts by mass: 18-30 parts of styrene, 5-15 parts of methyl methacrylate, 1-5 parts of 2-ethylhexyl acrylate, 5-14 parts of butyl acrylate, 0.5-1 part of acrylic acid, 0.6-1.2 parts of acrylamide, 0.8-2 parts of a high-density crosslinking monomer, 0.2-0.5 part of an initiator, 0.7-1 part of an emulsifier and 50-60 parts of water. 0.1-0.5 part of an oxidant, 0.1-0.5 part of a reducing agent, 1-5 parts of a pH regulator and 10-20 parts of an inorganic material; after the emulsion is coated to form a film, the hardness, the water resistance, the stain resistance, the low-temperature stability and the temperature change resistance are remarkably improved, and the acrylate emulsion with high hardness, high water resistance and high stain resistance can be prepared.

The invention discloses a separation method of inorganic powder in lithium battery positive and negative electrode materials, and relates to the technical field of lithium batteries. Comprising the following steps: taking a mixture of materials in the waste lithium battery, and pretreating the mixture to obtain pretreated powder; performing dry powder mixing on the pretreated powder and a surfactant to obtain powder after dry powder mixing, preparing slurry, and grinding the slurry to obtain dispersed slurry; and adding a cationic flocculant into the dispersed slurry, and after the dispersed slurry is precipitated and layered, separating the precipitated dispersed slurry to obtain a lower-layer precipitate and drying the lower-layer precipitate to obtain the inorganic powder. According to the method, a physical separation means is adopted, the carbon powder in the mixture of the positive electrode material and the negative electrode material in the waste lithium battery is accurately and efficiently separated, the inorganic powder after the carbon powder is separated is obtained, and reutilization of the inorganic powder is achieved.

The present application discloses a method for preparing a carbon material for a battery, comprising: filtering and concentrating papermaking black liquor to obtain liquid lignin; polymerization: adding a cross-linking agent to the liquid lignin for cross-linking and curing reaction to obtain a lignin polymer solid; pre-oxidation: pre-oxidizing the lignin polymer solid to obtain a lignin-based resin; pre-carbonization: pre-carbonizing the lignin-based resin in a non-oxidizing gas atmosphere to obtain a carbon material precursor 1; gas phase deashing: gas phase deashing the carbon material precursor 1 in a non-oxidizing gas atmosphere under the action of a halogen compound and / or a halogen element to obtain a carbon material precursor 2; calcination: crushing the carbon material precursor 2 and calcining it in a protective atmosphere to obtain a carbon material for a battery. The method of the present application effectively improves the expansion and foaming phenomenon during lignin carbonization, and the obtained carbon material has low ash content, controllable specific surface area, and excellent electrochemical performance. A lignin-based resin as mentioned above is also disclosed.

The invention belongs to the technical field of welding, and discloses and provides a maritime work steel high-performance non-preheating welding process determination method which comprises the following steps: acquiring a first cold crack sensitivity index required by non-preheating welding at a specific temperature and a critical constraint distance and a critical constraint degree of a base metal sample; obtaining the minimum diffusible hydrogen content of a welding material required in non-preheating welding, and selecting an actual welding material based on the minimum diffusible hydrogen content; the cold crack sensitivity coefficient of the base metal sample is used for optimizing the carbon equivalent of the base metal sample to obtain a new base metal; a second cold crack sensitive index smaller than the first cold crack sensitive index is obtained, and the new base metal corresponding to the second cold crack sensitive index serves as actual base metal; and the time t100 when the peak temperature of the actual welding material and the actual base metal after welding is cooled to 100 DEG C under different welding heat inputs and the critical cooling time tcr of the welding joint are obtained, and the welding heat input when the difference value between t100 and tcr is the maximum serves as the actual welding heat input. A quantitative analysis theory system is provided for developing the welding process, orthogonal tests are avoided, and the method is high in universality.

The invention belongs to the field of high polymer materials, and relates to a side-group siloxane functionalized polyolefin elastomer and a preparation method thereof. The side group siloxane functionalized polyolefin elastomer contains an ethylene structural unit, an alpha-olefin structural unit and a structural unit derived from alkoxysilyl cycloolefin; the alkoxyl-containing silyl cycloolefin is selected from at least one of compounds shown in the formula 1, and in the # imgabs0 # formula 1, a is an integer of 0-5; r1 and R2 are respectively and independently selected from alkyl groups of C1 to C10, alkoxy groups of C1 to C10, naphthenic groups of C4 to C10 or naphthenic alkoxy groups of C4 to C10; r3 is an alkyl group of C1 to C10 or a cycloalkyl group of C4 to C10; and R4 is hydrogen or alkyl of C1-C10. According to the functionalized polyolefin elastomer with the side group containing the alkoxy silane substituent group, the molecular weight of a copolymer is high, and the molecular weight distribution is relatively narrow.

The invention belongs to the technical field of polycarbosilane, and particularly relates to a synthesis method of polydimethylsilane and application of the polydimethylsilane in preparation of polycarbosilane. In the Wurtz polymerization reaction of polydimethylsilane, polar solvents such as crown ether, diethylene glycol dimethyl ether, hexamethylphosphoric triamide and polyether are added into a reaction system, and the polar solvents have a complexing effect on sodium ions, so that tight ion pairs can be promoted to become loose ion pairs, the concentration of active anions is greatly increased, and the reaction time is shortened; therefore, the initiation period of the reaction is shortened, the polymerization reaction speed is accelerated, the molecular weight of polydimethylsilane is improved, and the yield is improved; the molecular weight of the polydimethylsilane is increased, the pyrolysis activation energy of the polydimethylsilane is gradually reduced, and the prepared polycarbosilane has higher Si-H bonds, and is high in A-grade conversion rate and good in spinning performance; according to the method, original reaction equipment does not need to be changed, reaction process parameters are also in original design, and the method has practical application value.

The present invention discloses a polyurea-ceramic composite coating for the leading edge of a wind turbine blade and a preparation method thereof. The coating comprises aspartic acid ester polyurea and ceramics. The ceramics have good strength and hardness, and can improve the hardness and toughness of the coating as a whole, and improve the overall anti-rainwater erosion performance of the coating. Specifically, the polyaspartic acid ester polyurea is made of polyetheramine, diisocyanate, polyaspartic acid ester resin and isocyanate as raw materials, and the polyetheramine is a hydrophilic monomer, so that the system has good hydrophilicity, which is conducive to forming a water film on the leading edge surface of the wind turbine blade, and effectively buffering the impact of raindrops on the leading edge of the wind turbine blade.

The invention is applied to the technical field of polishing pad preparation, and particularly discloses a preparation method of a high-density and high-hardness foamed polyurethane polishing pad, which comprises the following steps: S1, raw material pretreatment; s2, a prepolymer synthesis step; s3, a foaming and forming step; s4, demolding and post-processing are carried out; and S5, sheet detection and formula optimization: detecting the hardness and density of the treated polishing pad finished product, and correspondingly adjusting the mixing ratio of the raw materials according to the detection result. According to the preparation method of the high-density and high-hardness foamed polyurethane polishing pad, polyether polyol and polyester polyol are mixed and then react with isocyanate, the polyether polyol and the polyester polyol do not react, and the polyether polyol and the polyester polyol jointly participate in the reaction of the isocyanate after being mixed, so that the high-density and high-hardness foamed polyurethane polishing pad is prepared. The generated polymer combines the advantages of polyether polyol and polyester polyol, and has stronger mechanical properties and chemical resistance than a polymer generated from a single component, so that the quality of a finished product of the polishing pad can be improved.

The invention relates to the technical field of high polymer materials, and particularly discloses a nuclear-grade cable for spent fuel aftertreatment and a preparation method of the nuclear-grade cable. Comprising the following steps: S1, taking hydroxyl-containing cyclotriphosphazene, tetra (4-hydroxybenzene) ethylene, oleic acid acyl chloride, guar gum hydroxypropyl trimethyl ammonium chloride, triethylamine and a mixed solvent, cooling, dropwise adding triethylamine in a nitrogen atmosphere, dropwise adding a phenoxyphosphoryl dichloride solution, stirring for reaction, filtering, and performing rotary evaporation to obtain a composite flame retardant; s2, polyethylene, aluminum hydroxide, a composite flame retardant and an anti-radiation agent are added into an internal mixer for mixing, a cross-linking agent is added, uniform mixing, extrusion and granulation are performed, and a cable material is obtained; the cable material is used for preparing an outer sheath layer of a nuclear-grade cable. S3, twisting a plurality of copper metal monofilaments to form a conductor, wrapping the conductor with an insulating layer, and wrapping the conductor with a polyimide film to form a wire core; a plurality of wire cores are twisted to form a cable core; a non-woven fabric wrapping tape layer and an outer sheath layer are wrapped outside the cable core; and obtaining the nuclear-grade cable.

The invention discloses high-crystallinity copolyester based on furandicarboxylic acid as well as a preparation method and application of the high-crystallinity copolyester. The structural formula of the high-crystallinity copolyester is as follows: # imgabs0 # R1 is-O (CH2) aO-, R2 is-O (CH2) bO-, a, b, x, y, z and n are integers, a = 2-6, b = 6-12, x = 1-10, y = 1-10, z = 1-10, and n = 20-100; and (x + z): y = 1: 1-1: 10. The present invention also provides a highly crystalline copolyester article made from the highly crystalline copolyester. The high-crystallinity copolyester disclosed by the invention not only has excellent crystallization capacity, relatively high crystallinity, excellent thermal stability and mechanical property, but also has excellent barrier property, and has obvious advantages in various gas barrier aspects compared with PET (Polyethylene Terephthalate) on the market; the material can be widely applied to the fields of high-temperature-resistant materials, express packages, food packages, food tableware and the like.

The invention provides a polycarbonate-polysiloxane copolymer as well as a preparation method and application thereof, and belongs to the technical field of polycarbonate material preparation. The polycarbonate-polyorganosiloxane copolymer comprises a polycarbonate block and a polyorganosiloxane block, and the polycarbonate-polyorganosiloxane copolymer comprises a polycarbonate block and a polyorganosiloxane block. A high-boiling-point solvent capable of simultaneously dissolving polysiloxane and polycarbonate is added, and a high-boiling-point cosolvent capable of improving intersolubility of polysiloxane and other monomers (an aromatic bisphenol compound and / or an aliphatic diol compound and diester carbonate) is introduced into a melt transesterification polycondensation method; in the ester exchange stage, the intersolubility of reaction monomers is improved, the conversion rate of polysiloxane is improved, and the transparency and molecular weight of the copolymer are improved.

The invention discloses a transformation method and application of a G protein coupled receptor, and belongs to the technical field of protein engineering. In order to improve the molecular weight of membrane protein, enable the enlarged part of the membrane protein and the original membrane protein to form a relatively rigid structure and further meet the structural analysis requirement of a cryoelectron microscope, the invention provides a method for transforming a G protein coupled receptor. The method comprises the following steps: co-expressing fusion protein GPCR (Glycine Polymerase Chain Reaction)-GFP10-11 and GFP1-9 fragments formed by GPCR and GFP10-11 fragments in a eukaryotic cell expression system, and adding GFP-clamp in the purification process; one amino acid at the specific site of GPCR is mutated into cysteine, glutamic acid at the 186th position of the amino acid sequence of GFP-clamp is mutated into cysteine, and a disulfide bond is formed between the amino acid and glutamic acid. The molecular weight of the modified G protein coupled receptor obtained by using the method can be increased to 85 kD or above, and the rigidity of the whole compound space structure is relatively strong, so that the modified G protein coupled receptor can be used for structural analysis of a cryoelectron microscope.

The invention discloses a high-performance bio-based polyester material and a preparation method thereof. The high-performance bio-based polyester material is prepared from the following components in percentage by mass: 95-99.5% of bio-based polyester, 0.4-4% of glycidyl ester and the balance of a catalyst. Epoxy groups of the catalyst and the catalytic glycidyl ester react with terminal groups of the bio-based polyester to achieve a chain extension crosslinking effect, and due to the improvement of the molecular weight and internal crosslinking, the performance of the bio-based polyester is greatly improved, and the bio-based polyester is easier to form during extrusion processing.

The invention discloses isosorbide type block copolycarbonate as well as a preparation method and application thereof, and belongs to the technical field of organic polymer materials. The problems that isosorbide polycarbonate in the prior art is low in molecular weight, deep in color and luster, fragile in material and the like are solved. The preparation method comprises the following steps: carrying out melt ester exchange polycondensation reaction on dihydric alcohol and isosorbide carbonate serving as raw materials to obtain dihydroxyl-terminated isosorbide ester glycol; rigid amorphous dihydroxyl-terminated isosorbide ester glycol and oligomeric flexible chain dihydric alcohol are connected together, and a molecular chain is reformed, arranged and branched to a certain extent, so that the isosorbide type block copolycarbonate is effectively synthesized. According to the method, the oligomeric flexible chain dihydric alcohol can be effectively introduced to improve the molecular weight and the mechanical property of the isosorbide polycarbonate, so that the problems that the isosorbide polycarbonate is too strong in structural rigidity, fragile in material, deep in color and the like in production and application are solved.