326 results about "N isopropyl acrylamide" patented technology

The invention discloses a preparing method for infrared response high-strength hydrogel for cartilago articularis repair. The preparing method mainly includes the operation steps that polysaccharide or protein is modified in a double bond forming mode through methacrylic acid, methacrylic anhydride and methacrylate substances, so that the polysaccharide or the protein has a double-bond group in a side chain and is capable of being polymerized to form the hydrogel. Under the action of an initiator and a cross-linking agent, N-isopropyl acrylamide and the polysaccharide or the protein modified in the double bond forming mode form the double-network high-strength hydrogel through in-situ polymerization. The prepared infrared response high-strength hydrogel is high in biocompatibility and excellent in mechanical property and has good application prospects in the field of cartilago articularis repair.

The present invention relates to a method and a wood preserving composition which comprises mixtures of a metal compound, complexing agents selected from ethanolamines, polyethylenimine, ammonia or a mixture of these compounds, and a vinyl based polymer selected from poly(vinyl alcohol) (PVA), poly(acrylamide) (PA), poly(N-vinyl pyrrolidone) (PVP) and poly(N-isopropyl acrylamide) (PNIPAM). The resulting metal amine solution can then be used to formulate a variety of metal-based cellulosic material preserving products.

The present invention relates to one kind of environment responding aquogel copolymer and its preparation process. The aquogel consists of: N-isopropyl acrylamide 10-90 wt% and methacrylate dextran derivative 10-90 wt%. The preparation process of the environment responding aquogel copolymer includes chemical modification of dextran with GMA to synthesize methacrylate dextran derivative, MA-Dex, with reaction activity; and subsequent copolymerization of MA-Dex and NIPA to obtain the said environment responding aquogel copolymer P(NIPA-co-MA-Dex). The aquogel copolymer has high temperature sensitivity and quick responding speed as well as high strength and excellent biocompatibility. The preparation process is simple, needs no special apparatus and is easy to realize in industry.

The invention discloses a preparation method of a double-sensitivity cyclodextrin supermolecule aggregate, belonging to the technical field of functional materials. The preparation method comprises the following steps of preparing a host molecule-photosensitive 4-hydroxycinnamic acid-cyclodextrin (4HCA-CD) by using 4-hydroxycinnamic acid (4HCA) to modify beta-cyclodextrin (beta-CD); using trithioester with adamantine (AD) at tail end as a chain transfer agent, and preparing temperature-sensitive object polymer-double-arm adamantine-poly(N-isopropyl acrylamide)-adamantine (AD-PNIPAM-AD) by using a reversible addition-fragmentation chain transfer free radical polymerization (RAFT) method; constructing a double-sensitivity supermolecule inclusion complex 4HCA-CD/AD-PNIPAM-AD by utilizing comprehensive performance of a beta-CD dewatering cavity and AD; and self-assembling the 4HCA-CD/AD-PNIPAM-AD to form the supermolecule aggregate which is capable of realizing reversible conversion in shape and size by changing light and temperature. The supermolecule aggregate prepared by the preparation method disclosed by the invention has good light/temperature double sensitivities and is capable of carrying out smart response onto external stimulus, so that the supermolecule aggregate has a wide application prospect in the fields of drug loading, controlled release, and the like.

The invention relates to a magnetic thermometer nm particle with biocompatibility, which has biocompatibility, and double response properties of magnetism and thermometer property, and the particle diameter thereof is 20 to 60 nm, and the magnetic responsibility is strong, and magnetic saturation intensity is 10.0 to 27.0 emu/g. The synthetic method of the magnetic thermometer nm particle with biocompatibility comprises: firstly, adopting chemical coprecipitation method to prepare magnetic Fe3O4 nm particle, and using silane coupler to hold surface modification, and then using the modified magnetic Fe3O4 nm particle as a seed, and having polyreaction with dextran, N-isopropyl acrylamide, finally obtaining the magnetic thermometer nm particle with biocompatibility. The magnetic thermometer nm particle with biocompatibility synchronously has double responses of magnetism and thermometer property, and has wide application prospect in the fields of drug release, protein and enzyme separation.

The invention discloses a method for preparing a hollow silica nanosphere by one step. The method comprises the following steps: mixing a poly-N-isopropyl acrylamide aqueous solution and an ethyl orthosilicate prehydrolysis solution at a temperature of 40 to 60 DEG C to react at a constant temperature for 160 to 180 hours; and carrying out ethanol washing, ultrasonic concussion, centrifugal separation and drying on a reaction liquid, and then obtaining the hollow silica nanosphere. The hollow silica nanosphere has a hollow core and mesoporous shell structure, the particle diameter is between 200 and 600 nm, and the shell thickness is between 30 and 100 nm. The invention also discloses the hollow silica nanosphere and the application. The method does not need to use an organic solvent to catalyze or further remove a template agent by high-temperature calcination or chemical corrosion, and can control the hollow nanosphere size and the shell thickness by simply changing the reaction temperature, the reaction time and the feed ratio.

Thermogelling polymers are described containing poly (n-isopropyl acrylamide). Solutions of this polymer, copolymers or mixtures of the polymer with a second polymer such as poly(ethylene glycol), poly (vinyl pyrrolidone) or poly(vinyl alcohol) are liquids at room temperature and solids at body temperature. Thus, also provided are methods of implanting a hydrogel into a mammal by injecting the solution as a liquid at a temperature below body temperature into a selected site in the mammal at a temperature below body temperature, which then undergoes thermal phase transition to form a solid hydrogel in situ in the body as the implant warms to body temperature. Methods for using these thermal gelling materials in various applications including nucleus pulposus replacement/augmentation, wound care, disk replacement, cartilage replacement, joint replacement, surgical barriers, gastrointestinal devices, cosmetic and reconstructive surgery, and breast enlargement are also provided.

The invention relates to an environment-response intelligent weave fabric and relative preparation. Wherein, adding the fabric which is induced by argon microwave low-temperature plasma to generate free group on surface, into the dual monomer solution of 2-acrylamide-2-methanesulfonic acid and N-isopropyl acrylamide that contains N and N'-methylene dual acrylamide cross linker to process graft polymerization reaction, while the bath ratio is 1:40, to graft the dual intelligent gel on the fiber macromolecule of fabric, to attain said inventive product. When the invention is dry, it has no difference from general fabric, but when it is wet, the gel will adsorb water to expand and block the slits between fibers, to reduce the water and gas permeability of fabric, and avoid outer penetrating into the inner layer of fabric to stop heat emission. The invention can be used to produce army waterproof clothes, heat-accumulation temperature adjustable special clothes, etc.

The invention relates to an N-isopropyl acrylamide (NIPA) polymer hydrogel and a synthetic method thereof. The hydrogel comprises the following components (wt%) of: NIPA 8-15%, low critical solution temperature (LCST) regulator 0-4%, initiation reducer 0.02-0.05%, crosslinker 0.1-0.15%, initiation oxidizer 0.03-0.07%, and water 91.85-80.73%. The synthetic method comprises the steps of: (1) determining the composition of the hydrogel; (2) dissolving an NIPA monomer in part of water to obtain an NIPA monomer aqueous solution; (3) adding the crosslinker in the NIPA monomer aqueous solution; (4) respectively dissolving the initiation reducer and the initiation oxidizer in part of water; (5) mixing the NIPA monomer aqueous solution and the aqueous solution of the initiation reducer in a container; (6) replacing the air on the surface and the surroundings of the container with nitrogen gas; (7) adding the aqueous solution of the initiation oxidizer into the container, mixing, and replacing with nitrogen gas for several minutes; (8) sealing the container, and reacting for several hours to obtain a gel product; and (9) washing with water to remove the toxicity of the residual non-reacted monomer on the surface of the gel product.

The invention relates to a vessel plug material used in intervene treatment. Wherein, said material is temperature-sensitive nanometer gel system based on polymer N-isopropyl acrylamide (PNIPAAm), which comprises polymer N-isopropyl acrylamide nanometer gel and dispersed medium, while the gel mass percentages is 3-20% and the particle diameter of temperature-sensitive nanometer gel is 50-1000nm. The inventive temperature-sensitive nanometer gel system also can contain developer, soluble antineoplastic. The invention can control the polymer monomer kinds and ratios, the crosslinker amount and the density of temperature-sensitive nanometer gel, to control the sol-gel transformation temperature of said system, and the inventive product has better external flow property and high sol-gel transformation speed, to be used to treat vessel plug, etc.

The invention discloses an intelligent hydrogel as well as a preparation method and an application thereof and a hydrogel. The intelligent hydrogel is P(NIPAM-co-CS)/Fe3O4 and comprises iron oxide, N-isopropyl acrylamide and chitosan. The preparation method comprises the following steps: dissolving FeCl2.4H2O and FeCl3.6H2O in a mixed solvent of ethanol and water and reacting to prepare hydrophilic Fe3O4 nanoparticles under the protection of nitrogen and by adopting ammonia water as a precipitating agent; ultrasonically dispersing the prepared Fe3O4 nanoparticles in a chitosan liquid, adding a temperature-sensitive monomer N-isopropyl acrylamide and in the presence of a crosslinking agent and an initiator and by adopting tetramethylethylenediamine as an accelerator, carrying out polymerization reaction to prepare the intelligent hydrogel P(NIPAM-co-CS)/Fe3O4 by virtue of a micro-emulsion polymerization method. The intelligent hydrogel can be applied in the preparation of a water body heavy metal ion adsorption-desorption agent for removing heavy metal ions in water body.

The invention provides a preparation method of polystyrene with a thermo-sensitive surface. The method comprises the following steps of: adopting benzophenone as a photosencitizer on the surface of polystyrene, initiating N-isopropyl acrylamide monomer or N-isopropyl acrylamide monomer and styrene monomer to occur graft copolymerization reaction by ultraviolet light and preparing the polystyrene with a thermo-sensitive surface layer. The preparation method can initiate homopolymerization of N-isopropyl acrylamide or copolymerization of styrene under the ultraviolet irradiation of 300 to 395nm at room temperature, and forms a layer of thermo-sensitive film with water-washing resistance and good transparency on the surface of the polystyrene. The method is simple, convenient and fast, is easy to operate, has low cost and can maintain good surface transparency of a culture dish of the polystyrene.

The invention belongs to the field of polymer material and biomedical engineering and in particular relates to a method for preparing temperature-sensitive amphipathic graft copolymer with chitosan as the main chain. The method comprises the following steps: with the protection of inert gases such as nitrogen and argon, hydroxide group or aminogroup in chitosan main chain are adopted to trigger ring opening polymerization of cyclic ester monomer; then the obtained terminal hydroxide group or aminogroup of aliphatic polyester are converted to bromine group; the bromine group is taken as macroinitiator to polymerize atomic transfer radical of N-isopropyl acrylamide, hydrophilic allyl monomer, thus obtaining the needed product. The temperature-sensitive amphipathic graft copolymer with chitosan as the main chain is provided with biological degradability, biocompatibility, biological activity and temperature sensibility, can be automatically assembled into stable nano micelle in water, thus enjoying wide application in fields such as drug controlled release carrier, soft tissue engineering support material, immunoassay, memory element switch, biosensor and the like. The synthetic method of the invention is simple and feasible, the raw materials can all be applied to industrialized production, thus enjoying very good value in popularization and application.

This invention discloses a method for preparing temperature-sensitive hydrogel with supermolecular structure. The present methods have such problems as residual corsslinking agent and pore-forming agent, low biocompatibility and low response speed. The method comprises: dissolving cyclodextrin in deionized water, adding glycidyl methacrylate, and stirring, adding N-isopropyl acrylamide, stirring in N2 atmosphere, adding initiator, sealing the container, heating in a water bath, reacting to prepare hydrogel, and soaking in deionized water after the reaction to obtain temperature-sensitive hydrogel with supermolecular structure. The method has such advantages as no need for corsslinking agent, easy operation, and no need for specific apparatus. The obtained hydrogel has supermolecular structure, and has such advantages as high temperature sensitivity and high biocompatibility.

The invention provides a preparation method of a self-repairing conductive double network structure hydrogel. The hydrogel is a carbon nanotube/chitosan double network structure hydrogel, a first network is formed by electrostatic interaction of carboxylated carbon nanotubes and chitosan, and a second network is a hydrophobic association network hydrogel obtained by free radical polymerization ofmain monomer acrylamide or N-isopropyl acrylamide and hydrophobic monomer octyl methacrylate, dodecyl methacrylate, hexadecyl methacrylate or long-chain aliphatic acrylate. The introduction of the carbon nanotubes provides excellent conductivity for the hydrogel, and the hydrophobic monomer can stably form a hydrophobic association center in an emulsifier, and has an obvious reinforcing effect onthe hydrogel, and the obtained hydrogel ahs significantly-improved strength. In addition, the presence of ionic and hydrophobic association effects provides a rapid self-healing property for the hydrogel, and the hydrogel is useful in bionic biology, flexible electronics, biosensors and other fields.

The invention relates to poly-N- isopropyl acrylamide-poly-amino acid two section copolymer and the manufacturing method. It is made from poly-N-isopropyl acrylamide that the equal molecular weight is 1000-10000. The poly-amino acid is poly-L-glutamic acid or poly-L- aspartic acid that the equal molecular weight is 1000-30000. The copolymer has double responsibility to temperature and pH in water solution. The pH responding range would alter around the content of benzyl group in poly-amino acid. And it could take biodegradation. The invention could be used as carrier that the in vivo target released to medicine and could be used as injectable intelligent responding hydrogel.

The invention discloses a preparation method of poly(N-isopropyl acrylamide)/oxidized graphene hydrogel. The preparation method comprises the following steps: at first, oxidizing graphite to obtain oxidized graphite; and then subjecting the oxidized graphite to radiation polymerization under a radiation source with a temperature of 60 DEG C to obtain the poly(N-isopropyl acrylamide)/oxidized graphene hydrogel. According to the preparation method, graphene oxide (GO) is dispersed into a water solution of (N-isopropyl acrylamide) NIPAM monomers and then the mixture is subjected to radiation polymerization to prepare the hydrogel. Multi-step reactions and organic solvent are not needed. The preparation method is simple and direct and is easy to control. The product is more pure and is more suitable for being used as a biological material. By changing the content of GO before polymerization, the amount of GO loaded on hydrogel can be easily controlled. Moreover, GO has excellent optical and thermal properties, and thus the poly(N-isopropyl acrylamide)/oxidized graphene hydrogel has an excellent light and heat sensitive property.

The invention discloses a two-block copolymer of poly-N-isopropyl acrylamide-polyamino acid and making method, which is characterized by the following: the number average molecular weight of poly-N-isopropyl acrylamide-polyamino acid is 1000-10000; the polyamino acid is poly-L-glutamic acid or poly-L-aspartic acid with number average molecular weight at 1000-30000; the molar percentage of amino acid carbobenzoxy is 0-90%; the invention uses hydrogen bromide or reducing method to strip benzyl through catalyzing and hydrogenating to obtain the product, which possesses double response for temperature and pH value in the solution; the copolymer can be biological decomposed to be discharged out of body through kidney directly, which can be carrier of target drug release and injectable intellectual response aquagel.

The invention relates to a dual-hydrophilic thermo-sensitive polymer/lactic acid polymer composite nanofiber felt and a preparation method thereof. The nanofiber felt comprises the following components: dual-hydrophilic thermo-sensitive polymer and lactic acid polymer with the mass ratio of 10:1. The preparation method comprises the following steps: (1) carrying out free radical polymerization reaction on glucaric acid divinyl ester and N-isopropyl acrylamide to obtain the dual-hydrophilic thermo-sensitive polymer; (2) dissolving the high polymer in a solvent, stirring for 1-4 hours, and carrying out ultrasonic degassing to obtain a spinning solution A; (3) dissolving the lactic acid polymer in the solvent, stirring for 1-8 hours, carrying out ultrasonic degassing to obtain a spinning solution B; and (4) mixing the spinning solution A with the spinning solution B, and carrying out electrostatic spinning to obtain the dual-hydrophilic thermo-sensitive polymer/lactic acid polymer composite nanofiber felt. According to the invention, the method is continuously feasible, the operation is simple and easy, industrialization is easy to realize, and the obtained nanofiber felt can be used for carrying medicines and control the release of the medicine; and the nanofiber felt can also be implanted into a release system and can be used in the fields of tissue engineering scaffold and the like.

The invention relates to a preparation method of a stable chitosan nano-micelle with CO2 responsiveness and temperature responsiveness. The preparation method comprises the following steps: under the protection of an inert gas such as argon and nitrogen, carrying out esterification reaction between the hydroxy group or the amino group in the main chain of chitosan and the reversible addition-fragmentation chain transfer (RAFCT) polymerization chain transfer agent for a carboxyl end group to obtain the RAFCT polymerized macromolecule chain transfer agent; under the initiating effect of azobisisobutyronitrile, carrying out RAFCT polymerization on N-isopropyl acrylamide and a N,N-dimethylaminoethyl methacrylate monomer to obtain the grafted copolymer taking chitosan as the main chain and having CO2 responsiveness and temperature responsiveness, dissolving the grafted copolymer in water to obtain the stable nano-micelle with CO2 responsiveness and temperature responsiveness. The stable chitosan nano-micelle with CO2 responsiveness and temperature responsiveness provided by the invention simultaneously has biodegradability, biocompatibility, bioactivity, CO2 responsiveness and temperature responsiveness, and is widely applied to the fields of controlled release drug carrier, biological intelligent switch, biosensor, and the like. The preparation method provided by the invention is simple and easy to carry out, the raw materials can be produced industrially, and therefore the preparation method has excellent popularization and application value.

The invention relates to temperature sensitive composite gold nano particles and a preparation method and catalytic application thereof. The temperature sensitive composite gold nano particles are compounded by using nano gold particles and poly (N-isopropyl acrylamide) (PNIPAM) grafted glucan polymer, and the diameter of the particles is 1 to 20 nanometers; the preparation method comprises the following process of: mixing and shaking chloroauric acid serving as a precursor, the PNIPAM grafted glucan polymer serving as a nucleating agent and a stabilizing agent and sodium borohydride serving as a reducing agent to obtain a product; and the temperature sensitive composite gold nano particles serving as a catalyst are used for regulating and controlling the temperature of the nitrophenol reduction reaction process to control the process and the stop of the reaction. The invention has the advantages that: the preparation process is simple; and the prepared temperature sensitive composite gold nano particles have high dispersion, good stability and temperature sensitivity, and are used as the catalyst for controlling the nitrophenol reduction reaction process.

The invention discloses a preparation method for a temperature sensitive response type intelligent ceramic composite membrane and a product. The product is obtained by chemical graft copolymerization of N-isopropyl acrylamide on the surface of a ceramic membrane. The invention takes the ceramic membrane as a basement membrane, takes the N-isopropyl acrylamide as a functional monomer, and adopts a method of chemical graft to prepare the temperature sensitive response type intelligent ceramic composite membrane. The prepared intelligent ceramic composite membrane can overcome the disadvantage of low mechanical strength of an intelligent membrane prepared taking an organic membrane as the basement membrane, has favorable chemical stability, long service life and the environmental sensitivity of a graft monomer, and is easy to disinfect and clean.

The invention belongs to the fields of intelligent high-molecular material and preparation method thereof, and discloses a semi-interpenetrating intelligent hydrogel and a preparation method and an application thereof. With N-isopropyl acrylamide and acrylamide as polymerization monomers and with polyethylene glycol diacrylate and polycaprolactone diacrylate as crosslinking agents, the semi-interpenetrating intelligent hydrogel is obtained by carrying out a crosslinking polymerization reaction under initiation of azobisisobutyronitrile. The obtained intelligent hydrogel allows semi-interpenetrating hydrophilic channels for communicating the gel interior and the gel surface to be formed through acrylamide auto-polymerization and copolymerization, so that the response speed of the intelligent hydrogel is further improved. The obtained semi-interpenetrating hydrogel can be used for preparing drug loading and releasing materials in the biomedical field.

The invention provides a novel high-molecular-block dispersing agent, a preparation method and an application thereof. The preparation method includes the following steps: performing polymerization to a monomer methacrylic acid, sodium styrenesulfonate and N-isopropyl acrylamide under the effects of an initiator and a chain transfer agent to generate a large-molecular chain transfer agent M-CTA; and mixing the large-molecular chain transfer agent M-CTA with the initiator to initiate polymerization of hydroxyethyl methylacrylate and allyl alcohol polyoxyethylene ether as monomers to prepare the high-molecular-block dispersing agent. The high-molecular-block dispersing agent can be applied in dispersion of nano titanium dioxide, calcium carbonate, printing ink pigment particles and the like.

The invention provides a gel microsphere product having temperature-pH dual-sensitivity. The average pore size of the gel microsphere is in a range of nanometers to 200 nm and the average grain size thereof is 1-100 microns. The preparation method comprises the following steps of: (1) providing an aqueous solution which is dissolved with water-soluble monomer N-isopropyl acrylamide, acrylic acid,an initiator and a cross-linking agent as an aqueous phase W; (2) providing oily substance which is dissolved with an oil soluble emulsifying agent and is insoluble with water as an oil phase O; (3) mixing the aqueous phase with the oil phase to obtain a W/O emulsion, agitating and introducing an inert gas; (4) keeping the inert gas atmosphere, adding an accelerant into the W/O emulsion, and polymerizing to obtain the gel microsphere at a temperature which is lower than the critical dissolving temperature of N-isopropyl acrylamide; and (5) washing the polymerized gel microsphere to obtain thegel microsphere product. The invention further provides application of the gel microsphere.