777 results about "Amide bonds" patented technology

The invention belongs to the technical field of flame retardants, and particularly relates to a high-thermal-stability polyphosphate flame retardant and a preparation method thereof. The DOPO is modified through the polyethylene glycol acrylate, methyl methacrylate and dicumyl peroxide composite solution, double bonds of the polyethylene glycol acrylate and P-H bonds of the DOPO can be subjected to nucleophilic addition to form stable C-P bonds, and thermal migration of the DOPO is hindered; dOPO has polymerization double bonds of methyl methacrylate and long carbon chains of polyethylene glycol acrylate, so that the compatibility of the polyphosphate flame retardant and a polymer substrate is improved, and phase separation is avoided; maleic anhydride grafted silicone oil is connected to the surface of an amino modified gamma-cyclodextrin-modified DOPO inclusion compound, so that the polyphosphate flame retardant has high thermal stability and high compatibility after long-chain alkyl modification; amino groups in the modified gamma-cyclodextrin react with maleic anhydride grafted silicone oil to generate an amido bond cross-linked network, so that the thermal migration of DOPO is reduced together, and the high thermal stability of the polyphosphate flame retardant is improved.

The invention relates to the technical field of coating surface preparation, in particular to an anticoagulant coating based on novel tick-derived anticoagulant protein Qinghaenin and a preparation method of the anticoagulant coating. The functional layer of the anticoagulant coating comprises the following components: anticoagulant protein Qinghaenin or a functional peptide fragment Qinghaenin 167-192 of the anticoagulant protein Qinghaenin, wherein the amino acid sequence of the functional peptide fragment is as shown in SEQ ID NO. 2. The preparation method of the anticoagulant coating comprises the following steps: by using a polydopamine coating as a substrate layer, covalently grafting through an amido bond, immobilizing anticoagulant protein Qinghaenin capable of inhibiting FXII factor activation or a functional peptide fragment Qinghaenin 167-192 thereof on the surface of a medical polymer material, and successfully constructing a novel anticoagulant coating. Compared with an unmodified medical polymer material, the modified coating can significantly enhance the hydrophilic performance of the material and inhibit platelet adhesion and activation, finally effectively prolongs the in-vitro blood coagulation time, and shows excellent anticoagulation performance.

The present invention relates to a composite sulfide electrolyte, and a preparation method therefor and a use thereof. The composite sulfide electrolyte has a three-dimensional crosslinked structure formed by connecting a sulfide electrolyte and a dynamic bond-containing crosslinked polymer by means of chemical bonds. The polymer contains a sulfur element and exhibits relatively higher stability when interacting with the sulfide electrolyte, the chemical crosslinking between the sulfide electrolyte and the dynamic bond-containing crosslinked polymer is formed by means of multiple chemical bonds, such as a disulfide bond and an amido bond, and a strong binding force and self-healing function are provided, in order to simultaneously solve the problems of interfacial delamination and cracking caused by mechanical stress inside the sulfide electrolyte. When applied in an all-solid-state battery, the composite sulfide electrolyte can improve the limiting current density and cycle stability of the all-solid-state battery.

The invention provides a cyclic peptide as well as a preparation method and application thereof. The cyclic peptide has an amino acid sequence # imgabs0 # represented by formula (1) (wherein X is a Lys residue modified with a fatty acid molecule, and a line connecting Arg and Lys represents an amide bond. The cyclic peptide prepared by the invention has wide antifungal activity and antibacterial activity on drug-resistant bacteria; meanwhile, the biotoxicity and the protease degradation resistance are high, and the in-vivo antibacterial effect of the cyclopeptide can be prolonged. The cyclic peptide can be applied to preparation of anti-bacterial and anti-fungal infection drugs, and can be used as an excellent substitute drug or an auxiliary drug of existing antibiotics. The method for preparing the cyclic peptide is simple, raw materials are easy to obtain, and industrial production can be achieved.

The invention relates to the field of preparation of polyurethane damping materials, in particular to a preparation method of a repairable polyurethane damping material based on multiple hydrogen bonds and metal coordination. Compared with a traditional damping material, the damping material has a higher damping temperature range and has a good damping effect at the temperature of-20 DEG C to 60 DEG C. Multiple reversible hydrogen bonds are introduced through diamine containing amido bonds, the material is endowed with self-repairing and high mechanical strength, and damping and self-repairing performance is further enhanced through pyridine nitrogen atom metal coordination. Starting from molecular structure design, multiple hydrogen bonds and metal-ligand coordination bonds constructed on a polyurethane molecular main chain play a role in synergistic enhancement, energy can be effectively dissipated through dissociation and recombination of the multiple hydrogen bonds and fracture and association of the metal coordination bonds, and the energy consumption is reduced. The polyurethane material is endowed with excellent damping performance and self-healing capability by the dual dynamic action.

The invention discloses a tough full-bio-based polylactic acid / polyamide composite material and a preparation method thereof, and belongs to the technical field of polymer composite material preparation. The tough polylactic acid / polyamide composite material comprises polylactic acid, bio-based polyamide, a core-shell amide modified material, a hydrolysis stabilizer, an antioxidant and a chain extender. The core-shell amide modified material is prepared by filling a functional elastomer copolymer with amino nanoparticles. The core-shell amide modified material formed on the basis of the amino nanoparticle reactive filling functional elastomer copolymer has a micro core-shell structure formed in situ and a large number of amido bonds, so that the number of hydrogen bonds between molecular chains of a blend system is increased, and entanglement and intermolecular acting force between micro molecular chains of the blend material are improved; therefore, the system compatibility is improved, the absorption of the material on external stress and energy is enhanced, more obvious plastic deformation is generated when the material is stressed and deformed, and the material is endowed with better mechanical properties.

The invention provides a low-temperature-impact-resistant food packaging material and a preparation method and application thereof.The low-temperature-impact-resistant food packaging material is prepared from, by mass, 100 parts of polylactic acid, 1-10 parts of modified layered double hydroxide and 5-40 parts of hyperbranched polyester; wherein the modified layered double hydroxide is obtained by treating layered double hydroxide with a composite anionic surfactant and then treating the treated layered double hydroxide with an organic cationic compound with a long alkyl chain; the composite anionic surfactant comprises a first anionic surfactant and a second anionic surfactant; wherein the first anionic surfactant comprises sodium dodecyl sulfate; the second anionic surfactant comprises a sulfonate anionic surfactant containing an amido bond and a catechol structure. Through the formula design, the impact toughness of the material at low temperature can be improved while the mechanical property of polylactic acid is maintained, and the material can be suitable for the field of food packaging.

The invention discloses a nanofiber functional dressing for wound healing of burns and scalds, and belongs to the technical field of wound repairing dressings. The dressing is prepared through double-layer electrostatic spinning and comprises a hydrophilic nanofiber layer and a hydrophobic nanofiber layer. The hydrophobic nanofiber layer is prepared by electrostatic spinning of an antibacterial composite modified material and isocyanate-terminated oligomeric lactic acid, and the antibacterial composite modified material is prepared by acylating chlorination of (9I)-2, 4, 8, 10-tetraoxaspiro [5.5] undecane-3, 9-dipropionic acid, reaction of the acylating chlorination product and N, N-bis (2-benzimidazole methyl) amine, and quaternization of benzyl chloride. The tetrooxaspiro rigid structure improves the thermal stability and inhibits the molecular chain from absorbing water and expanding; the quaternized benzimidazole group destroys cell membranes through positive charges, and can efficiently resist bacteria. An amido bond in the hydrophilic layer and a urea bond formed by the antibacterial material and an isocyanate group remarkably improve the liquid absorption capacity; the hydrophobic layer provides mechanical support and ductility; two layers of interfaces are fused through heat treatment, the overall tearing strength is improved, and the joint movement requirement is met.

The invention relates to the technical field of antibacterial polyamide fiber preparation, and discloses a polyamide fiber with antibacterial performance and a preparation method thereof.The polyamide fiber is prepared from, by weight, 100 parts of PA6 slices, 10-15 parts of graphene oxide, 1-5 parts of surface amination mesoporous catechin-silver-loaded zirconium phosphate and related auxiliaries, after surface amination mesoporous catechin-silver-loaded zirconium phosphate and graphene oxide are subjected to amide linkage, the surface amination mesoporous catechin-silver-loaded zirconium phosphate and amide groups of polyamide fibers form a hydrogen bond network, the surface amination mesoporous catechin-silver-loaded zirconium phosphate and the amide groups of the polyamide fibers are mutually combined to play a synergistic effect, the interface binding energy is increased, and antibacterial components can stably exist in the polyamide fibers; meanwhile, the mesoporous structure provides multi-channel support, induces cracks to expand along the edge of a pore and increases the length of a fracture path, so that the stress transfer efficiency is obviously improved, and the problem of internal stress concentration caused by the addition of large-particle high-content rigid particles is avoided.

The invention belongs to the technical field of antibacterial peptides, and particularly relates to an LL-37 derived antibacterial peptide and application thereof. According to the invention, 17-29aa of the LL-37 antibacterial peptide is used as a core fragment and is connected with an amino acid sequence shown as SEQ ID NO: 1 or SEQ ID NO: 2 through an amido bond, the antibacterial activity of the obtained antibacterial peptide is obviously higher than that of the LL-37 antibacterial peptide, and the antibacterial peptide shows an obvious bactericidal effect on clinical drug-resistant bacteria such as acinetobacter baumannii, pseudomonas aeruginosa, escherichia coli, staphylococcus aureus, klebsiella pneumoniae and the like; meanwhile, the cytotoxicity and hemolytic activity are weak, drug resistance is not prone to being generated, bacteria can be rapidly killed in vivo through multiple mechanisms, no obvious cytotoxicity exists, the bacterium load in tissue is remarkably reduced, and the lifetime of a bacterium-infected mouse is prolonged.

The invention discloses a high-barrier material based on a PET aminolysis monomer and a preparation method of the high-barrier material, and belongs to the technical field of high polymer materials. The preparation method comprises the following steps: carrying out aminolysis reaction on polyethylene glycol terephthalate (PET) to prepare a dihydric alcohol monomer containing an amido bond, and carrying out polymerization reaction on the dihydric alcohol monomer and aliphatic dibasic acid to prepare a polyesteramide (PEA) material. The prepared PEA material has excellent oxygen barrier property and toughness, the oxygen barrier property of the PEA material is obviously superior to that of a PET material, and the barrier property and mechanical property of the PEA material can be regulated and controlled by changing the length of a methylene chain segment of the aliphatic dibasic acid monomer. The aliphatic dibasic acid monomer can be derived from biomass resources, the reaction condition is mild, the process is simple, and the method is suitable for industrial large-scale production.

The invention belongs to the field of biomedical materials, and discloses a hydrogel patch with piezoelectricity, conductivity and high adhesion and a preparation method and application of the hydrogel patch. Polyvinyl alcohol (PVA) and acrylic acid (AA) serve as polymer frameworks of the hydrogel patch; the invention relates to a nano-zinc oxide / poly (3, 4-ethylenedioxythiophene) / poly (styrenesulfonic acid) (PEDOT: PSS) composite conductive adhesive, which comprises nano-zinc oxide (ZnO) as a piezoelectric material, poly (3, 4-ethylenedioxythiophene)-poly (styrenesulfonic acid) (PEDOT: PSS) as a conductive material, and N-hydroxysuccinimide acrylate (NHS-AA) as an adhesive functional monomer. According to the invention, active ester groups in the N-hydroxysuccinimide acrylate are utilized, so that the patch can quickly form covalent amido bonds with amino groups on the surface of a tissue in a dry state, firm adhesion is realized, local nerve repair can be effectively promoted through a piezoelectric effect, a novel ideal material is provided for disease treatment, and the patch has wide application prospects. Wide clinical application prospects are realized in the field of biological medicines.

The present invention relates to a polymer having a main chain, wherein the main chain comprises linear amide bonds and a heteromonocyclic moiety containing a nitrogen atom, wherein the main chain does not contain peptide bonds, or wherein, based on the total number of linear amide bonds in the main chain, the proportion of peptide bonds in the main chain is at most 30%, and wherein, based on the total weight of the polymer, the proportion of the heteromonocyclic moiety containing a nitrogen atom is from 5% by weight to 25% by weight. The present invention also relates to a product or article and the use of the polymer for manufacturing or producing the product or article.

The present disclosure discloses a medical hydrogel, formed by in-situ crosslinking an aldehyde-terminated multi-arm star polyethylene glycol and a polyamino compound, wherein the aldehyde group and the multi-arm star polyethylene glycol are linked by a chemical bond such as an ether bond, an amide bond, an ester bond, a urethane bond, an imine bond, or a urea bond, and the molar ratio of the amino in the polyamino compound to the aldehyde group in the aldehyde-terminated multi-arm star polyethylene glycol is 0.4-4.4:1. The polyamino compound is polylysine or a mixture of polylysine and polyethylenimine in a molar ratio of 2-30:3. The hydrogel of the present disclosure gels rapidly, has a long-term stability in an aqueous solution, and still has good swelling property and stability after a plurality of radiations, and thus can be used as a medical radiotherapy protection spacer for radiation protection.

The invention relates to the field of hydrophilic thermosensitive resin, in particular to hydrophilic thermosensitive resin as well as a preparation method and application thereof, and aims to solve the problems that an existing thermosensitive material is insufficient in hydrophilicity, an existing hydrophilic material is insufficient in thermosensitive performance, and a resin material cannot give consideration to both the hydrophilic material and the hydrophilic material at the same time. According to the resin, an imidazole structure is introduced into polyacrylamide and grafted into PNIPAM to form an amido bond, the hydrophilic performance of the PNIPAM is improved, ethyl cellulose is grafted onto amino-treated silicon dioxide to form an amido bond, and the hydrophilic performance of the resin is improved together with modified polyacrylamide blended PNIPAM; when the resin is applied to a specific medium or environment, the resin can show a corresponding response behavior on absorption or release of moisture according to the change of environment temperature, realizes effective regulation and control and induction on temperature and humidity, and can be applied to temperature-sensitive medical treatment, electronic packaging and other emerging technical fields.

The invention relates to the technical field of liquid crystal polymers, and discloses a high-temperature-resistant, electricity-conducting and heat-conducting graphene-LCP material and a preparation method thereof.The preparation method comprises the steps that a diacid monomer, p-hydroxybenzoic acid and 4, 4 '-bis (4-hydroxyphthalimide)-benzamido benzene are subjected to a carboxyl reaction, liquid crystal polyarylester is obtained and mixed with graphene oxide, and the high-temperature-resistant, electricity-conducting and heat-conducting graphene-LCP material is obtained. The liquid crystal polyarylester molecular chain contains an imide ring, so that the thermal decomposition mass loss temperature of the liquid crystal polyarylester LCP material can be improved. The liquid crystal polyarylester contains amido bonds and forms strong interaction with hydroxyl and carboxyl on the surface of the graphene oxide, the interfacial compatibility between the graphene oxide and the liquid crystal polyarylester can be improved, the graphene oxide does not need surface modification and has good dispersity in the LCP material, a conductive path is formed, and the conductivity and the antistatic performance are improved.

The invention belongs to the technical field of functional nano materials, and particularly relates to a preparation method of a detachable engine type braking nano motor, a nano drug carrier is jointly composed of HMSN and CAT modified PNA, tetraethyl orthosilicate serves as a silicon source, and solid silicon dioxide balls are synthesized; on the basis, tetraethyl orthosilicate is used as a silicon source, CTAB is used as a pore-forming agent to synthesize mesoporous silica coated solid silica spheres; etching the core silicon dioxide ball through sodium carbonate to obtain a hollow mesoporous silicon dioxide ball; then, amino modification is carried out on the CAT modified PNA2 through 3-aminopropyltrimethoxysilane, PNA1 is connected with HMSN through an amido bond, and a double-chain structure is formed by the CAT modified PNA2 and PNA1 through complementary base pairing. According to the nano motor provided by the invention, the engine CAT of the nano motor can be detached by adding the unwinding chain PNA3, so that in-vivo deceleration and braking are realized.

The invention relates to the technical field of biomedical material modification, in particular to a sulfhydrylation biocompatible polymer derivative, a preparation method thereof, extracellular matrix imitating injectable in-situ cross-linked hydrogel and application thereof. According to the invention, a pre-acylation strategy is firstly carried out on the biocompatible polymer containing both amino and carboxyl, so that a three-dimensional cross-linked byproduct formed by coupling of self amido bonds is avoided, meanwhile, the number of side chain carboxyl for sulfhydrylation modification is increased, and the accurate and adjustable pre-acylation rate can optimize the physical and chemical properties of the derivative; meanwhile, a disulfide bond is used as a protective precursor, active sulfydryl is introduced through amido bond coupling, self-oxidation of the active sulfydryl in the reaction process is avoided, sulfydryl activity is guaranteed, hydrazine-containing reagents are avoided, safety is further improved, virus residues and immunological rejection risks are avoided, universality is high, and the application prospect is wide; and in combination with a high-concentration preparation method, the method has the advantage of large-scale production, and further widens the industrial application potential.

The invention relates to the technical field of composite materials, in particular to a surface modified MXene reinforced nylon composite material and a preparation method thereof, and the surface modified MXene reinforced nylon composite material comprises the following components in parts by mass: 70-85 parts of nylon resin, 1-8 parts of amido bond and imine bond surface modified MXene, 1-8 parts of a compatibilizer, 0.2-0.8 part of a lubricant, 0.2-0.8 part of an antioxidant and 0.2-1.0 part of a coupling agent. According to the preparation method disclosed by the invention, the MXene with amido bond and imine bond surface modification is obtained through surface modification of the MXene, so that uniform dispersion of the MXene in a nylon matrix is facilitated, the interface bonding force between the MXene and nylon resin is enhanced, and the mechanical property, the heat resistance, the electromagnetic shielding property and the like of the composite material are remarkably improved.

The invention relates to the technical field of high polymer materials, in particular to an anti-aging thread gluing material and a preparation process thereof. Comprising the following steps: preparation of aluminum-doped zinc oxide, tannic acid modified aluminum-doped zinc oxide, ferulic acid modified nylon fiber and modified nylon master batch preparation of the thread gluing. According to the invention, groups of tannic acid and aluminum ions and zinc ions of aluminum-doped zinc oxide are driven by heat energy of a reflux reaction to simultaneously generate chelation-dehydration condensation to form a five-membered ring chelate, so that a compact coating layer is formed on the surface, and the coating layer is simple in component and has very stable chemical bonds; the ultraviolet light stability of aluminum-doped zinc oxide is enhanced, the layer can generate hydrogen bond / pi-pi interaction with nylon amido bonds, the interface bonding strength is improved, the particle size is kept at the level of no filter pressure fluctuation in the spinning process, and the volume resistivity of nylon fibers is reduced.

The present disclosure relates to a process for making a polyamide grease thickening agent from an oligomeric intermediate. Particularly, the polyamide grease thickening agent may include at least two para-substituted aromatic moieties, have a molecular weight in a range of from 450 g / mol to 3500 g / mol, and may include at least four amide bonds.

The invention provides a porphyrin functionalized carbon nanotube compound. Medium-tetra (4-carboxyphenyl) porphyrin is covalently connected to the surface of an aminated carbon nanotube through an amido bond to form the compound. Stable amido bond connection is formed through amino-carboxyl condensation, and the bond energy is obviously higher than that of an ester bond. The invention also provides a preparation method of the porphyrin functionalized carbon nanotube compound, which comprises the following steps: carrying out carboxyl activation treatment on the meso-tetra (4-carboxyl phenyl) porphyrin by adopting a catalytic system consisting of N, N '-dicyclohexylcarbodiimide and N-hydroxysuccinimide; the preparation method comprises the following steps: performing ultrasonic treatment on aminated carbon nanotubes in N, N-dimethylformamide, adding the aminated carbon nanotubes into an activated meso-tetra (4-carboxyphenyl) porphyrin solution prepared in the step 1, performing stirring reaction at room temperature, and performing suction filtration and freeze drying to obtain a target product, namely the porphyrin functionalized carbon nanotube compound. A mild room-temperature stirring process is adopted, so that the dependence of a solvothermal method on high-temperature and high-pressure equipment is completely avoided, and the production cost is remarkably reduced.

The invention relates to the technical field of fibers, and discloses an easily biodegradable polyester-nylon composite fiber and a preparation process thereof.The preparation method comprises the steps that 2-(2-acrylamido ethyl formate) benzoic acid is subjected to graft modification to obtain modified polylactic acid, and the modified polylactic acid, polyethylene glycol terephthalate PET and nylon 66 resin are subjected to blending melt spinning to obtain the polyester-nylon composite fiber. The modified polylactic acid improves the compatibility between the PET and the nylon 66 resin, so that the polyester-nylon composite fiber has higher mechanical properties, and the tensile strength and the elongation at break are obviously improved. The polylactic acid has better biodegradability, and the introduced ester group also has biodegradability, so that the biological decomposition rate of the fiber is improved. The modified polylactic acid contains a large amount of hydrophilic carboxyl and amido bonds, so that the moisture regain of the composite fiber is improved, and the modified polylactic acid can be better applied to hydrophilic moisture absorption fiber textiles.

The invention belongs to the technical field of coatings, and discloses a water-based epoxy coating for automobiles and a preparation method thereof.The water-based epoxy coating is prepared by preparing water-based rigid epoxy resin, water-based flexible epoxy resin, a diamine curing agent and a block polymer as components in the water-based epoxy coating and matching the four components with a step-by-step coating process. High-activity amido in the curing agent and rigid resin form a high-density network to endow the top layer with hardness, the curing agent and flexible resin form hardness and softness to improve the toughness of the bottom layer, epoxy groups of the block polymer and low-activity amido in the bottom layer are covalently anchored, carboxyl and the amido in the top layer form amido bonds, firm molecular bridges are constructed, interlayer reinforced connection is achieved, and the bonding strength is improved. The coating has high hardness, high toughness and excellent interlayer adhesive force, and solves the problem of non-uniform performance caused by low crosslinking density and side reaction of the traditional waterborne epoxy coating.

The invention belongs to the technical field of medicinal chemistry, and particularly relates to N-methylation modified cyclopeptide and application thereof. On the basis of a GluA2-3Y polypeptide sequence, chemical modification and transformation of amido bond N-methylation and head-tail cyclization are carried out, the N-methylation modified cyclopeptide with stable metabolism and good permeability is obtained, and the endocytosis of a GluA2AMPA receptor is blocked to protect nerve cells, so that the GluA2AMPA receptor can be effectively inhibited, and the GluA2AMPA receptor can be effectively inhibited. The invention also provides application of the cyclic peptide in preparation of drugs for treating cerebral arterial thrombosis.

The invention relates to the field of polymers, and discloses a high-elastic light nylon elastomer and a hydrolytic polymerization preparation method thereof. The high-elastic light nylon elastomer is prepared from a monomer A and a monomer B through hydrolysis ring-opening polymerization, at least one of the monomer A and the monomer B is caprolactam substituted by ortho-position or meta-position alkyl. According to the invention, caprolactam substituted by ortho-position and meta-position alkyl of an amido bond and caprolactam are combined according to different proportions in a hydrolysis ring-opening polymerization form, alkyl chains with different lengths are introduced into molecular chains of polycaprolactam (PA6), and the alkyl chains as side chain groups can reduce the overall density of the molecular chains and improve the elasticity; in addition, the alkyl chain side group can be used as a physical entanglement point, so that the toughness of the material is improved, and finally, the nylon elastomer with high elasticity, light weight and adjustable molecular structure is prepared.

The invention relates to the technical field of single-molecule devices, in particular to a single-molecule device for detecting small-molecule gas based on supramolecules and a preparation method of the single-molecule device. The monomolecular device comprises a functional molecule and a graphene electrode pair, wherein the functional molecule is connected between the graphene electrode pair through an amido bond. A cucurbituril hydrophobic cavity structure in the functional molecular structural formula can contain and capture target small molecular gas, gas molecules of different volumes are selectively included through multiple weak interaction, a dynamically-adjustable subject-object compound structure is formed, and then switching type sensing detection on the small molecular gas is achieved. The amino terminal of the end part of the main bridging unit in the functional molecule can be connected with the carboxyl terminal of the graphene point electrode in a covalent bond manner, and amide condensation molecular chain connection is formed at the two ends of the graphene point electrode, so that the stability of a monomolecular device is improved. The preparation method provided by the invention is simple in process, mild and controllable in reaction condition and beneficial to large-scale production.

Provided is a composition for forming a laminated separator for a non-aqueous electrolyte secondary battery, the composition being capable of reducing the amount of increase in air permeability of the laminated separator and improving heat resistance. This composition for forming a laminated separator for a non-aqueous electrolyte secondary battery contains a resin having an amide bond, the resin having an amide bond containing a component eluted into N-methyl-2-pyrrolidone, and the amount of the component eluted into N-methyl-2-pyrrolidone is less than the amount of the component eluted into N-methyl-2-pyrrolidone relative to the weight of the entire resin having an amide bond. The content of the component eluted into N-methyl-2-pyrrolidone is greater than 25.0% by weight and 45.0% by weight or less, and the content of the component eluted into N-methyl-2-pyrrolidone is greater than 25.0% by weight and 45.0% by weight or less.

The invention belongs to the technical field of biomedical materials, and discloses a conductive composite scaffold of a bionic nerve orientation structure and a preparation method of the conductive composite scaffold of the bionic nerve orientation structure, and the conductive composite scaffold of the bionic orientation structure is formed by compounding a structural layer and a functional layer, the structural layer is an oriented nanofiber membrane (made of a natural high-molecular polymer containing amino and a synthetic high-molecular polymer), the functional layer is ionic conductive hydrogel (made of a natural high-molecular polymer containing amino and a natural high-molecular polymer containing carboxyl), and the structural layer and the functional layer are compounded through the action of an amido bond; the amido bond is formed by reacting amino of the oriented nanofiber membrane with carboxyl of the ionic conductive hydrogel under an acidic condition; the preparation method comprises the following steps: compounding the structural layer and the functional layer by using glacial acetic acid by adopting a chemical cross-linking method to prepare the conductive composite nerve scaffold with the bionic orientation structure. According to the invention, electric signal transmission between cells can be realized, and the efficiency of damaged nervous tissue repair is improved.

The invention discloses a preparation method of a pH response type core-shell structure cerium oxide abrasive, a chemical mechanical polishing solution and a chemical mechanical polishing process, and belongs to the technical field of chemical mechanical polishing process.The method comprises the following steps that S1, a cerous nitrate aqueous solution and a precipitator are mixed, and cerium oxide (CeO2) nanoparticles are prepared through a hydrothermal reaction; s4, polyacrylic acid-block-polyethylene glycol and the CeO2 (at) mSiO2-NH2 are subjected to a reaction, the reaction product is grafted to the surfaces of the particles through amido bonds, and CeO2 (at) mSiO2 (at) PAA-b-PEG is obtained; and S5, dispersing the obtained CeO2 (at) mSiO2 (at) PAA-b-PEG in a trivalent cerium salt solution, and enabling Ce < 3 + > to be loaded on a PAA chain through ion exchange, so as to obtain CeO2 (at) mSiO2 (at) PAA-b-PEG < 3 + >. The chemical mechanical polishing solution can achieve high removal in the sensing stage, the polishing early stage and the polishing middle stage and high protection in the polishing later stage.