84results about How to "High graft density" patented technology

The invention provides poly (gamma-propargyl-L-glutamate)-polyamino acid segmented copolymer. The poly (gamma-propargyl-L-glutamate)-polyamino acid segmented copolymer is presented as the formula (I). Small molecules containing primary amino radical serve as an initiator, and the poly (gamma-propargyl-L-glutamate)-polyamino acid segmented copolymer is obtained through the gradual ring cleavage reaction of gamma- propargyl-L-glutamate-N-carboxylic acid anhydride and amino acid-N- carboxylic acid anhydride. The side chain of the segmented copolymer is propargyl which is easy to modify, has high reactivity and is beneficial to functional small molecules which are subjected to bonded azide and have biological activity or environmental responsiveness, and the bonding process cannot lead to the breakage of amino acid backbones and is not affected by the amount and steric hindrance of functional small molecules. The segmented copolymer has good biocompatibility after being functionalized and can be applied in fields such as targeted drug delivery, organizational projects and protein separation and detection.

The invention relates to a method for preparing a stimulating responsive polymer brush, in particular to a polymer brush which can modify a surface and has stimulating responsiveness to temperature, and belongs to the technical field of micro nano material preparation. The stimulating responsive polymer brush is obtained by performing surface cleaning on a substrate by using a mixed solution containing concentrated sulphuric acid and hydrogen peroxide, performing epoxy silane coupling agent self-assembly and performing graft by adopting a photoinitiator. The method fixes a thioxanthone photoinitiator containing coinitiator amine on the surface of a base material by self-assembly technology, prepares the polymer brush by surface photo-initiation polymerization, is simple in operation, has the initiator with high graft intensity, high efficiency and speed of initiation polymerization, can be widely suitable for monomers capable of performing photo-initiation polymerization, and has wide application prospect.

The invention relates to an alginate-chitosan microcapsule modified via in situ covalent PEG grafting. The structure of the microcapsule is divided into two parts, i.e., a microcapsule membrane and an inner core, wherein the microcapsule membrane is a polyelectrolyte composite hydrogel membrane formed by chitosan and alginate, the surface of the membrane is modified via in situ covalent PEG grafting, and the inner core is an alginate liquid or alginate hydrogel environment containing living cells. Because of resistance to protein adsorption, the microcapsule is applied to living cell encapsulation and used as an immunoisolation carrier for cell transplantation.

The invention discloses a gradient molecular brush polymer. A main chain of the gradient molecular brush polymer is a copolymer of methyl methacrylate and hydroxyethyl methylacrylate, and a side chain of the gradient molecular brush polymer is polyacrylic acid; and the weight-average molecular weight Mw of the gradient molecular brush polymer is 89600-146900, and the molecular weight distribution is 1.25-1.45. The gradient molecular brush polymer disclosed by the invention is small in molecular weight distribution, high in grafting density, and high in adsorption capacity; and a method for preparing the gradient molecular brush polymer is simple. The gradient molecular brush polymer prepared by adopting the method is accurate and clear, and the molecular structure of the polymer is easily controlled.

The invention discloses a semi-interpenetrating network nano hybrid hydrogel and a preparation method and an application thereof. Firstly, chitosan is modified to prepare water soluble carboxymethyl chitosan (CMCS); then N-isopropylacrylamide (NIPAM), CMCS and (carboxyl functionalized) carbon nanotubes are subjected to in-situ free radical crosslinking polymerization reaction, and the semi-interpenetrating network nano hybrid hydrogel with different composition ratios of NIPAM, CMCS and the nanotubes is obtained. The prepared novel nano hybrid hydrogel has relatively high swelling rate, appropriate volume phase transition temperature and pH phase transition point, and high drug loading amount and continuous controllable drug release behavior. The hydrogel pharmaceutical preparation can be used as a promising hydrophilic oral drug carrier, is used for targeted release of oral vaccines, polypeptides, proteins and anticancer drugs, has low toxicity, and can be used for long-term treatment of colon cancer and the like.

The invention relates to a pH-responsive three-dimensional ordered macroporous controlled-release material. The sizes of macropores and communicating windows of the pH-responsive three-dimensional ordered macroporous controlled-release material are uniform, the sizes of the macropores are 100-1000nm, the sizes of the communicating windows are 40-120nm, and the pore volume is 1.3-2.8 cm<3>/g; the substrate is monodisperse three-dimensional ordered macroporous crosslinked polystyrene with windows which are mutually communicated, and a pH-responsive polymer chain section is introduced into the substrate by an atom transfer free-radical activity-controllable graft polymerization method; and the uncurling-curling action of the pH-responsive polymer chain section under different pH values is utilized to control the opening and closing of the communicating windows among the macropores: as the pH value increases, macromolecule chains gradually uncurl, and the pore windows are gradually closed, thereby realizing the controllable release of the contained filler. The pH-responsive three-dimensional ordered macroporous controlled-release material has wide application values in the controlled-release fields of biomedicine, medicine controlled-release systems, organized enzymes, slow release-embedding of catalysts, and the like.

The invention relates to a polyester film, which belongs to the technical field of surface modification of organic film materials, and in particular to a preparation method for a surface-grafted polyacrylic acid lead polyester film. The invention provides a preparation method for a surface-grafted polyacrylic acid lead polyester film, which can contribute to realizing uniform surface grafting and has high grafting density. The method is characterized in that: the polyester film material is subjected to a series of surface treatment, a bromo-ester initiator is fixed on the surface of the polyester film material, and polyacrylic acid lead is grafted to the surface of the polyester film with a surface initiated atom transfer free radical polymerization method. The method has a simple process and a good modifying effect. By grafting the polyacrylic acid lead with a cross-linked structure formed by ion bonds on the surface of the polyester film with the method, the surface electrics and surface free energy of the polyester film can be improved effectively, and the surface performance of the modified polyester film can be controlled by changing reacting time.

The invention discloses a method for performing surface treatment on a material for boosting cell growth and resisting biological pollution, which comprises the following steps: firstly, performing activating treatment on a material surface, and performing surface self-assembly reaction; and then fixing amphoteric-ion molecules and polyethylene glycol molecules with the characteristics of resisting biological pollution and extracellular matrix proteins or albumen polypeptides for boosting cell growth on the material surface in turn, thereby obtaining a material with the characteristics of boosting cell growth and resisting biological pollution. By performing surface treatment on the material according to the method provided by the invention, the material surface is simultaneously endowed with the capabilities of resisting biological pollution and boosting cell growth. The method is applied to the fields of biological materials, tissue engineering, nanometer material research, and the like.

The invention relates to a DEAE dextran-modified agarose gel-based chromatography medium and a preparation method and application thereof. The method includes the steps that first, the molecular weight of DEAE Dextran for grafting is selected; next, the concentration of a DEAE Dextran aqueous solution is controlled; then, the time of diffusion before DEAE Dextran coupling is determined; finally, the reaction time of coupled DEAE Dextran and the concentration and volume of sodium hydroxide are determined. The DEAE dextran-modified agarose gel-based chromatography medium has a strong adsorption property for protein under different modification densities, shows a high adsorption capacity and a high adsorption rate and improves separation efficiency. The medium is convenient to clean and degerm, easy to regenerate and good in biocompatibility. The preparation method is simple and harmfulless and has broad application prospects in efficient and rapid separation and purification of protein.

The invention discloses a thrombus filter capable of realizing delayed recovery and a preparation method of the thrombus filter and particularly discloses a blood compatible coating. The blood compatible coating comprises a polyacrylic acid layer and a polyethylene glycol layer, and 2-methacryloyloxyethyl phosphorylcholine is covalently linked with the surface of the polyethylene glycol layer. Theinvention further discloses medical apparatus such as the thrombus filter coated with the blood compatible coating. According to the technical scheme, thrombogenesis and endothelial tissue growth canbe better inhibited. The whole surface coating is adjustable in thickness and surface grafting amount and can well bear stress and strain actions in apparatus assembly and release processes, molecules are firmly combined without falling off, and mechanical properties of the apparatus are not affected.

The invention relates to the field of polymer synthesis. The invention provides a preparation method of an ultra-high graft density polymer molecular brush. The method comprises the following steps: firstly, preparing a SiO2/Si substrate by using a single-crystal silicon wafer, and then self-assembling an initiator monomolecular layer on the surface of the SiO2/Si substrate, wherein an initiator is 22-(trichlorosilyl)docosa-2-bromo-2-phenylacetate; finally, under nitrogen protection, enabling the product to react with cuprous bromide, styrene, pentamethyl diethyl triamine and toluene to prepare the ultra-high graft density polymer molecular brush. The results of the embodiments show that the thickness of the polymer molecular brush is 55-65 nm, and the graft density of the polymer molecular brush is 1.21-1.23 chains/nm<2>.

The invention discloses a method for reducing friction coefficient by surface finishing, which belongs to the technical fields of organic chemical grafting finishing and friction-pair surface modification treatment. The method includes: performing surface activating treatment for a friction pair by ultraviolet irradiation or plasmas, coating silane solution on the surface of the friction pair for multiple times for chemical finishing; disposing the friction pair into lubricants required by different working conditions so that the finished friction pair can be lubricated sufficiently; and enabling the friction pair to start operating. The friction coefficient can be simply and conveniently reduced by about one order of magnitude from the original friction coefficient by the method, and further, the fine friction reduction effect in a long time is achieved, and the method can be applied to various friction pair surfaces requiring friction reduction.

The present invention discloses a light-extinction heat-dissipating coating material, which comprises the following raw materials by weight: 1-2 parts of calcium linoleate soap, 1-2 parts of magnesium myristate soap, 12-15 parts of a styrene-maleic anhydride copolymer, 6-10 parts of propargyl alcohol, 90-100 parts of tetrahydrofuran, 4-7 parts of graphene, 16-20 parts of nanometer silica, 0.2-0.3 part of a silane coupling agent KH560, 700-800 parts of dimethylformamide, 4-5 parts of sodium nitride, 0.04-0.05 part of aluminum trichloride, 1.6-2 parts of a 2-3% sodium ascorbate solution, 1.8-2 parts of a 2-3% copper sulfate solution, 160-170 parts of high-density polyethylene, 0.7-2 parts of polyimide, 6-10 parts of diatomite, 0.8-1 part of castor oil polyoxyethylene ether, 3-4 parts of barium stearate, and 1-2 parts of chlorinated paraffin. According to the present invention, the diatomite, the polyimide, the calcium linoleate soap and the like are added, such that the mirror surface reflection effect of the paint film surface light can be reduced and the rough surface can be formed so as to achieve the light extinction effect.

The invention discloses acrylic acid acidized polyacrylate capable of realizing ultraviolet curing as well as a preparation method and an application of acrylic acid acidized polyacrylate. Single functional monomers including MMA (methyl methacrylate), BA (butyl acrylate) and HEMA (hydroxyethyl methylacrylate) and bifunctional monomers including GMA (glycidyl methacrylate) are adopted for copolymerization, polyacrylate resin is obtained, and various properties such as weather fastness, film-forming property, water resistance, solvent resistance and the like of the polyacrylate resin are improved. Acrylic acid and hydroxyl as a lateral group contained in main chains of the polyacrylate resin are adopted for acidification, so that the grafting density of double bonds can be greatly increased, part of hydroxyl is reserved in a polyacrylate copolymer through adjustment of the acidification degree, the copolymer has a higher curing speed, has quite excellent dispersing and stabilizing effects on pigments and has outstanding functions in the aspect of photo-curing printing ink configuration.

The invention discloses a straw fiber doped polyaniline electromagnetic shielding material and a preparation method of the straw fiber doped polyaniline electromagnetic shielding material. The preparation method comprises the following steps: under the condition of -8 DEG C to 0 DEG C, dropwise adding an oxidation solution into a raw material solution containing a polyaniline monomer and straw fibers by adopting a peristaltic pump; slowly stirring; after dropwise adding, stopping stirring and continually reacting for 10h to 16h; after reacting, filtering and centrifuging and washing with absolute ethyl alcohol for 3 to 5 times; after drying in vacuum, preparing the straw fiber doped polyaniline electromagnetic shielding material. The preparation method of the shielding material is simple; raw materials are cheap and easy to obtain; the shielding material has high shielding efficiency, a wide range and good industrialized production prospect.

The present invention discloses an Eva emulsion heat radiating coating. The Eva emulsion heat radiating coating is prepared from the following raw materials in parts by weight: 2-4 parts of calcium fluoride, 6-10 parts of an Eva emulsion, 12-15 parts of a styrene and maleic anhydride copolymer, 6-10 parts of propargyl alcohol, 90-100 parts of tetrahydrofuran, 4-7 parts of graphene, 16-20 parts of nano silicon dioxide, 700-800 parts of dimethylformamide, 4-5 parts of sodium nitride, 0.04-0.05 part of aluminium trichloride, 1.6-2 parts of a 2-3% sodium ascorbate solution, 1.8-2 parts of a 2-3% copper sulfate solution, 120-130 parts of high density polyethylene, 0.7-1 part of ricinoleic acid, 3-4 parts of dimethyl Methylphosphorate, 2-3 parts of diphenyl silandiol, 0.7-1 part of ammonium molybdate, 1-2 parts of polybenzimidazole fiber and 0.4-0.5 part of a silane coupling agent KH560. According to the present invention, by adding the Eva emulsion, the compatibility of materials among resin can be improved, the dispersibility of particles is improved, and the heat-conducting and heat radiating effect is improved.

The invention discloses a preparation method capable of preparing a superparamagnetic Fe3O4 nanorod with controllable size and dispersity in a large scale, belonging to the multidisciplinary fields like polymer active polymerization process, functional polymer molecular design and inorganic crystal growth. The method comprises the following steps: (1) with an ionic liquid AMIMCl as a solvent and anhydrous dimethylformamide and N-methylpyrrolidone as a diluent and an acid absorbent, modifying hydroxyl on the chain of cellulose by using 2-bromoisobutyryl bromide so that a macromolecular initiator capable of being used for atom transfer radical polymerization is obtained; (2) by utilizing a continuous polymerization ATRP technology and a click chemistry reaction, respectively preparing a series of brush-shaped di-block polymers, i.e., cellulose-g-[PAA-b-PS] and cellulose-g-[PAA-b-PEG]; and (3) on the basis of a solution phase synthesis method, and with a certain amount of the above-mentioned prepared brush-shaped di-block polymers as a monomolecular template and FeCl2.4H2O, FeCl3.6H2O and NH3.H2O as a precursor compound system, preparing the superparamagnetic Fe3O4 nanorod with oil dispersity and water dispersity.