183 results about "Surface initiated" patented technology

Methods for surface-initiated atom transfer radical polymerization, which can utilize a catecholic alkyl halide initiator.

An article having a nonfouling surface thereon is comprises: (a) a substrate having a surface portion; (b) a linking layer on the surface portion; and (c) a polymer layer formed on the linking layer, preferably by the process of surface-initiated polymerization of monomeric units thereon, with each of the monomeric units comprising a monomer core group having at least one protein-resistant head group coupled thereto, to thereby form a brush molecule on the surface portion. The brush molecule comprising a stem formed from the polymerization of the monomer core groups, and a plurality of branches formed from the hydrophilic head group projecting from the stem. Methods of making and using such articles, are also described.

Multiple-layer hydrogels and methods of forming hydrogels having multiple layers are disclosed. The hydrogels are formed of prepolymerization solutions comprising monomers or macromers, particularly polyethylene glycol. The layers are covalently bonded, and the hydrogels may comprise two or more layers.

An article such as a biosensor having a nonfouling surface thereon is described. The article comprises: (a) a substrate having a surface portion; (b) a linking layer on the surface portion; (c) a polymer layer comprising brush molecules formed on the linking layer; and (d) optionally but preferably, a first member of a specific binding pair (e.g., a protein, peptide, antibody, nucleic acid, etc.) coupled to the brush molecules. The polymer layer is preferably formed by the process of surface-initiated polymerization (SIP) of monomeric units thereon. Preferably, each of the monomeric units comprises a monomer (for example, a vinyl monomer) core group having at least one protein-resistant head group coupled thereto, to thereby form the brush molecule on the surface portion. Methods of using the articles are also described.

An article such as a biosensor having a nonfouling surface thereon is described. The article comprises: (a) a substrate having a surface portion; (b) a linking layer on the surface portion; (c) a polymer layer comprising brush molecules formed on the linking layer; and (d) optionally but preferably, a first member of a specific binding pair (e.g., a protein, peptide, antibody, nucleic acid, etc.) coupled to the brush molecules. The polymer layer is preferably formed by the process of surface-initiated polymerization (SIP) of monomeric units thereon. Preferably, each of the monomeric units comprises a monomer (for example, a vinyl monomer) core group having at least one protein-resistant head group coupled thereto, to thereby form the brush molecule on the surface portion. Methods of using the articles are also described.

The invention relates to a surface comblike polymer hydrophilic modified artificial lens and a preparation method thereof. The preparation method of the surface comblike polymer hydrophilic modified artificial lens comprises the following process steps of carrying out surface treatment on a clean artificial lens by using an amino functional group contained silane coupling agent to enable the surface of the clean artificial lens to have an amino group; grafting a carboxyl functional group contained RAFT (Reversible Addition-Fragmentation Transfer) chain transfer agent on the artificial lens by using a chemical method; and carrying out in-situ polymerization on a hydrophilic monomer molecule on the surface of the artificial lens by using an RAFT polymerization reaction method initiated on the surface of the artificial lens to form a hydrophilic comblike polymer to obtain the surface comblike polymer hydrophilic modified artificial lens. The surface comblike polymer hydrophilic modified artificial lens has the advantages that the condition that the artificial lens has toxic and side effects to non-targeting cells when being applied to a traditional drug coating is avoided, and the artificial lens with high biocompatibility is obtained.

The invention discloses a universal and efficient material surface modification method which comprises the following steps: 1) preparing a dopamine solution; 2) treating a substrate surface, washing, and preserving for later use; drying a substrate material in a blowing manner before being used; putting a substrate into the dopamine solution, and drying in the blowing manner for later use; 3) grafting a PEI (Polyethyleneimine) layer on the basis of a dopamine coating, preparing a Tris*HCl solution, and sealing for preservation; preparing a polyethyleneimine (PEI) solution for later use; putting the substrate coated by a PDA layer into the polyethyleneimine (PEI) solution, sealing the opening with a preservative film, stirring at room temperature for reaction, grafting the polyethyleneimine (PEI) layer, performing reaction, taking out by using tweezers, and blowing for later use; 4) inoculating an activated initiator; 5) performing surface initiation polymerization, immobilizing the initiator on surfaces of different substrates, and preparing different types of polymer brushes on the surfaces of different substrates by using a surface initiation polymerization method. The method has the advantages of being gentle and universal.

A composite of silica aerogel and a hydrogel synthesized by and a method for the sequential formation thereof including the encapsulation of hydrophobic aerogels with PEG hydrogel via photoinitiated polymerization. The aerogel-hydrogel composite has two layers: the outer layer hydrogel layer is hydrophilic, whereas the inner aerogel core is hydrophobic.

The invention relates to a method for preparing polymer brush films with multiple stimulation responses by homogeneous phase atom transfer radical polymerization (ATRP). According to the method, the polymer brush films are N,N-diamido ethyl methacrylate polymers and have multiple stimulation responses on temperature, pH value, salt and a solvent. The homogeneous phase ATRP preparation method comprises the following steps of: synthesizing an initiator omega-(2-bromoisobutyramide)alkyl silane coupling agent; assembling the initiator on the clean surface of a substrate; and performing surface-initiated atom transfer radical polymerization in a homogeneous system. According to the method, the grafting density and film thickness of a polymer brush can be regulated and controlled by regulating the assembly density and the content of bulk phase monomers of the initiator on the surface of the substrate, so that the polymer brush films which have different structures and multiple stimulation responses can be obtained. The method is mild in reaction condition, easy to control, adjustable in grafting density, high in polymerization efficiency and wide in applicability.

The invention relates to a preparation method and application of an Au / PILs (Polymeric Ionic Liquids) / PPyNTs (Polypyrrole Natotubes) composite material. The adopted technical scheme is that the preparation method comprises the following steps of firstly, synthesizing ionic liquid-modified polypyrrole nanotubes (ILs / PPyNTs); secondly, by taking 1-vinyl-3-ethylimidazole bromide salt as a monomer and taking 2,2-azobisisobutyronitrile as an initiator, initiating a polymerization reaction on the surfaces of the polypyrrole natotubes to obtain polymeric ionic liquid-modified polypyrrole nanotubes (PILs / PPyNTs); finally, uniformly mixing the PILs / PPyNT with an HAuCl4 solution; by taking sodium borohydride as a reducing agent, performing in-situ reduction of AuCl<4-> on the surfaces of the PILs / PPyNT to obtain Au / PILs / PPyNTs. According to the preparation method disclosed by the invention, the polymeric ionic liquids are used as connectors for combining conductive polymer polypyrrole with gold nanoparticles to obtain the Au / PILs / PPyNTs composite material which has better detectability for epinephrine.

The invention provides an anti-pollution polyvinylidene fluoride hollow-fiber membrane and a preparation method thereof. The anti-pollution polyvinylidene fluoride hollow-fiber membrane is characterized by being a polyvinylidene fluoride hollow-fiber membrane subjected to amphoteric ionization of amino acid. The preparation method comprises the steps that 1, the surface of a PVDF hollow-fiber membrane is treated by adopting sodium borohydride and other chemical agents, and an active site is introduced; 2, 2-bromine isobutyryl bromine is utilized to fix an initiator to the surface of the membrane; 3, amino acid methacrylamide or amino acid methacrylate is grafted to the surface of the membrane by adopting an SI-ATRP method. The surface-initiated atom transfer radical polymerization (SI-ATRP) method is utilized to graft zwitter-ions of the amino acid to the surface of the PVDF hollow-fiber membrane, and the high-hydrophilicity and high-pollution-resistance hollow-fiber membrane is prepared.

The invention discloses a matrix with selectivity for micromolecule MALDI-TOF MS (Matrix-Assisted Laser Desorption / Ionization Time of Flight Mass Spectrometry) detection and an application thereof. The matrix is graphene oxide grafted 4-vinylbenzeneboronic acid, and takes 4-vinylbenzeneboronic acid as a monomer; the 4-vinylbenzeneboronic acid is grafted to graphene oxide which is subjected to bromine functionalization by triggering atom transfer radical polymerization reaction on the surface, thereby preparing the matrix. The graphene oxide grafted 4-vinylbenzeneboronic acid disclosed by the invention can act as the MALDI-TOF MS matrix for selectively recognizing such micromolecule compounds containing cis-form adjacent dihydroxy structure, as cis-form adjacent dihydroxy compounds in saccharides, phenols and nucleoside; the minimum detection limit can reach 1pmol / mL around, and the selectivity and flexibility are both very high.

The invention provides a magnetic hydrophilic molecular imprinting composite material which can be suitable for various severe environments and has the pure water combination property. The magnetic hydrophilic molecular imprinting composite material takes a de-templated organic polymer molecular imprinting microsphere with a surface branchknot provided with chain polymer brushes as a center, the de-templated organic polymer molecular imprinting microsphere with the surface branchknot provided with the chain polymer brushes generates the chain polymer brushes through a surface initiated active free radical polymerization reaction, and multiple inorganic magnetic nano-particles are connected to each chain polymer brush through a covalent organic reaction. The composite material synthesizes the template molecule recognition capacity of the organic part and the magnetic response of the inorganic part, due to the fact that the inorganic magnetic nano-particles of the composite material are modified on the MIP microsphere through an irreversible covalent bond, good magnetism can be kept under various severe conditions, and the composite material can be repeatedly used. The invention further provides a preparation method of the composite material. The method is simple, easy to implement and low in cost.

The invention discloses a method for realizing efficient graft polymerization of acrylonitrile on the surface of silica gel microparticles by utilizing a mercapto-Ce(IV) salt redox initiation system. The method comprises the following steps of: (1) surface modification of silica gel by using a mercapto-containing coupling agent: reacting silica gel microparticles in a methane sulfonic acid aqueous solution, then adding activated silica gel microparticles to a toluene solvent, and adding gamma-mercaptopropyl trimethoxy silane (MPMS) as a coupling agent to prepare modified silica gel microparticles MPMS-SiO2 containing mercapto on the surface; and (2) graft polymerization of acrylonitrile: adding the modified microparticles MPMS-SiO2, DMF (dimethyl formamide) and AN (acrylonitrile) monomer to a four-neck flask, introducing nitrogen for 30 min, then adding a water solution dissolved with ammonium cerous sulfate and concentrated sulfuric acid, and reacting to obtain grafted microparticlesPAN / SiO2. In the method disclosed by the invention, the mercapto-Ce(IV) salt redox initiation system is utilized to initiate graft polymerization, and the active spots are located on the surface of acarrier, thus the method has high grafting degree and is a high-efficiency surface-initiated grafting method.

The invention discloses a preparation method of surface modified nano particles and application of a product thereof. The method comprises the following steps of: reacting the surfaces of nano particles, atom transfer radical polymerization (ATRP) surface initiator and 2-bromoisobutyryl with silicon chlorine bond to anchor the ATRP surface initiator on the surfaces of the nano particles, and then performing ATRP with methacrylate monomer, catalyst, coordination agent and the like to prepare acrylate polymer modified inorganic nano particles. Therefore, the ATRP method for modifying the nano particles has controllability on the nano particle surface grafted acrylate polymer, the advantages of the nano particles are fully exerted, and the effects of enhancing and toughening the nano particles and the like are achieved under the condition of low adding amount; meanwhile, the chain length distribution of the acrylate polymer is uniform, so the dispersibility and the stability of the modified nano particles in an acrylate coating are improved; and the abrasion resistance of the coating is improved, and high transparency of the coating is kept at the same time.

The invention relates to an environment-friendly preparation method of multi-hydroxyl polymer molecular brush, belonging to the technical field of the synthesis of polymer. The multi-hydroxyl polymer brush which is good in protein adsorption resistance and easily modified by a bio-molecular detection probe is synthesized on the surface of a solid support material by surface-initiated atom transfer radical polymerization under the environment-friendly conditions, i.e. room temperature, pure water, nontoxicity and the like. The preparation method of the multi-hydroxyl polymer molecular brush comprises the following steps of: surface treatment of a substrate, assembly of an amino silane coupling agent, modification of an initiator, preparation of the multi-hydroxyl polymer molecular-modified substrate, and functional modification of the active halogen atom at the tail end of the polymer. The polymerization of the environment-friendly preparation method can be operated under the full water phase and the room temperature, and is simple in technology, non-toxic and environment-friendly; the end group of the obtained molecular brush can be functionally modified; and the polymer contains a mass of end hydroxyl, so that the molecular brush is good in water solubility, high in protein adsorption resistance, and suitable for biology, medicine, drug and food safety detection kits, biological drug carriers, heterogenous catalyst carriers, water absorbing materials and the like.

The invention discloses a method for grafting 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer on a titanium-base material surface. A layer of middle bridging groups, namely organic phosphate or phosphate monoester which respectively forms chemical bonding with the titanium-base material surface and the MPC polymer is prepared on the titanium-base material surface and the MPC polymer by a self-assembled monolayer method; and the MPC polymer is grafted on the titanium-base material surface by a surface-initiated atom transfer radical polymerization method. In the prepared simulative functionalized titanium-base material of the method, the MPC polymer on the surface of the simulative functionalized titanium-base material has strong bonding force with the titanium-base material and has better histocompatibility and better blood compatibility. The invention has simple process and is easy to realize.

The invention belongs to the technical field of material modification and discloses a quaternized polymer brush antibacterial material based on a Si-ATRP (Surface-initiated Atom Transfer Radical Polymerization) method and a preparation method of the antibacterial material. The method comprises the following steps: (1) reacting a substrate material modified with hydroxide radical and / or amino on the surface with bromoisobutyryl bromide so as to obtain a substrate material fixed with an initiator; (2) carrying out a polymerization reaction on the substrate material and acrylamide monomers in aninert atmosphere and water in the presence of a catalytic system so as to obtain a substrate material with a polymer brush on the surface; and (3) carrying out an amide degraded reaction on the substrate material with the polymer brush on the surface, soaking in an organic solution of iodomethane to perform quaternarization, washing, and drying, thereby obtaining the quaternized polymer brush antibacterial material. The method disclosed by the invention is simple and low in cost, and the quaternized polymer brush can be stably grafted onto the surface of the substrate material, so that the substrate material has excellent antibacterial property and is high in safety and convenient for industrialized production.

A polymer-brush-based, surface-modification strategy for friction and wear reduction in hard contact under boundary-lubrication conditions is proposed, specifically for a non-aqueous environment. Surface-initiated Atom Transfer Radical Polymerisation (SI-ATRP) was employed for the synthesis of three different oil-compatible, hydrophobic polymer brushes based on alkyl methacrylates. This study presents polymerisation kinetics, chemical characterization by means of Fourier transform infrared spectroscopy (FTIR) and surface morphologies observed in atomic force microscopy (AFM). The lubrication properties of the anchored polymers were evaluated macroscopically by means of ball-on-disk methods and on the nanonewton scale by lateral force microscopy (AFM / LFM) and showed significant reduction in friction up to contact pressures as high as 460 MPa. The frictional response of surface-grafted polymers is shown to depend strongly on the compatibility of the polymer with the chosen lubricating fluid. Their good tribological performances have also been proven with watchmaking lubricants. These results do make the prevent invention a suitable candidate for a watchmaking application (such as at the balance pivot or the escapement) in order to increase the efficiency and reliability of the movements.

The invention relates to a preparation method and an application of an efficient hydrophilic modified anti-pollution polyether sulfone film. The preparation method comprises physical blending hydrophilic modification and chemical grafting hydrophilic modification of a pure polyether sulfone film: synthesizing a hydrophilic block polymer by virtue of a surface initiated reversible addition fragmentation chain transfer method (RAFT), and physically blending the hydrophilic block polymer with polyether sulfone, so as to prepare a PES / PAA-F127-PAA film; and synthesizing a high hydrophilic substance NH2-PDMAPS by virtue of an activator regenerated by electron transfer-atom transfer radical polymerization method (ARGET ATRP), and preparing the efficient hydrophilic modified anti-pollution polyether sulfone film by virtue of a chemical grafting method based on blending modification. The preparation method has the beneficial effects that molecules are designed by virtue of two efficient and environment-friendly RAFT and ARGET ATRP polymerization methods, the structure is novel, reaction conditions are mild, and a hydrophilic modification method has a relatively obvious effect and further has wide application prospects in oil-water separation field.

The invention discloses a method for preparing solid-phase microextraction fibers with a polyion liquid bonding coating on a metal wire carrier, particularly relates to a preparation method by utilizing a surface-initiated atom transfer radical polymerization reaction to graft an ionic liquid on the metal wire in a situ polymerizing manner. The novel method is characterized in that the method comprises the steps of adopting the metal wire as the carrier, performing chemical silvering on the surface of the metal wire firstly, then performing hydroxylation on the silvered layer, bonding an atom transfer radical polymerization initiation site, and preparing the polyion liquid bonding coating on the surface of the metal wire with the ionic liquid containing alkenyl as a monomer by utilizing the surface-initiated atom transfer radical polymerization technology. The solid-phase microextraction fibers prepared by the preparation method disclosed by the invention have the advantages of high mechanical strength, good coating stability, good extraction property and the like, can be used for enrichment analysis of trace components of samples of food, environment, drugs and biochemistry and the like, and are very good in application potential.

The invention discloses an antipollution self-cleaning polyvinylidene fluoride membrane and a method for producing the same, wherein a raw polyvinylidene fluoride membrane which contains initiator is firstly produced, and then radical polymerization is initiated on the surface of the raw polyvinylidene fluoride membrane, so the antipollution self-cleaning polyvinylidene fluoride membrane can be obtained. The technology of the method is simple, the method is easy to operate, expansive instruments are not required, the method is easy to industrially carry out, the produced antipollution self-cleaning polyvinylidene fluoride membrane has good antipollution performance, the main chain structure of polyvinylidene fluoride is kept undamaged, so the good physical properties of the polyvinylidene fluoride membrane are maintained.

The invention specifically relates to a method for preparing a fluorine-silicon segmented copolymer modified inorganic material through surface-initiated activators regenerated by electron transfer-atom transfer radical polymerization under the condition of a low catalyst concentration, belonging to the field of technical materials. According to the invention, a silane coupling agent and a chemical reagent containing an initiator site are respectively used to treat an inorganic material, and an initiator is modified on the surface of the material; then surface-initiated activators regenerated by electron transfer-atom transfer radical polymerization is employed for successive initiation of polymerization the two monomers consisting of 3-methacryloxypropyltrimethoxylsilane and heptafluorobutyl methacrylate so as to prepare the fluorine-silicon segmented copolymer modified inorganic material. The method uses a weak reducing agent to continuously reduce a passivating agent in a system, generates an activator, catalyzes atom transfer radical polymerization of the monomers, consumes a small amount of oxygen hard to thoroughly remove in the system in situ, substantially reduces the amount of a catalyst used in a polymerization system and shortens time needed for subsequent purification operation.

A process for preparing the structure controllable composite inorganic nanoparticle / polymer ultra-thin film includes synthesizing organic metal salt monomer containing double bond, surface graft reaction of substrate, surface initiated active free radical polymerizing reaction to produce precursor film, and in-situ growth to obtain the composite ultra-thin film. Its advantages are high adhesion to substrate, hardness, chemical stability and high temp resistance, and controllable thickness.

The invention discloses a hydrophilic chromatographic packing as well as a preparation method and application thereof. The packing is hydrophilic polymer-silica gel hybridization packing generated by in-situ polymerizing GMA-G hydrophilic monomers on the surface of silica gel particles through a surface-initiated atom transfer radical polymerization method. The surface of the hybridization packing is highly coarse, so that the specific surface area is relatively high. The concentration and separation of glycopeptides or oligosaccharide in a standard glycoprotein, oligosaccharide and plasma complicated sample can be successfully realized by utilizing a solid phase extraction column and a high efficiency liquid phase chromatographic column, which are filled with the hydrophilic polymer-silica gel hybridization packing. The selective concentration and separation effect is obvious, and 47 varieties of oligosaccharide glycoforms can be identified in the plasma glycoprotein; moreover, the desalting treatment on the sample can be realized in the concentration process, and the loss of the sample can be reduced. The application value in the separation analysis of the complicated biological sample is relatively good.

Surface active sensors comprising imprinted functional polymer matrices tailor made to detect specific chemical species of interest, and a label free, surface initiated molecular imprinting technology for applications in surface active sensors are provided.

The invention belongs to the technical field of functional nanoparticle assembly, and specifically relates to a method of preparing binary nanoclusters with nanoparticle as a structural unit and microemulsion droplets as a template, and preparing a polymer with binary nanoclusters as a core through surface-initiated polymerization. A new method for shell-composite nanoclusters. It includes three steps: synthesis of nanoparticles, preparation of nanoclusters, and surface-initiated polymerization. Oil-soluble nanoparticles can be synthesized by two-phase method, phase transfer method, and high-temperature pyrolysis method, and the size of nanoclusters can be regulated by changing the amount of surfactant and the concentration of nanoparticles. The invention is a new method for preparing bifunctional nano-clusters and compounding them with polymers, which realizes the integration and optimization of various nano-particle functions. After compounding with polymers, it can not only improve the stability of nano-clusters, but also introduce polymerization The special properties of materials can be obtained to obtain nano-micro-scale multifunctional composite materials, which have broad application prospects in the research fields of biology, catalysis, sensing, and optoelectronics.

The invention relates to cellulose nanocrystal hydrophobic porous powder and a preparation method thereof. Hydrophobic vinyl monomer polymerization is initiated on the surface of a cellulose nanocrystal by using a free radical polymerization initiating system in an aqueous medium to realize hydrophobic modification of the surface of the cellulose nanocrystal; the cellulose nanocrystal is uniformlywrapped by a polymer, so that the cellulose nanocrystal is prevented from being agglomerated due to hydrogen-bond interaction after being dried; and a complex porous network structure is formed in the powder under the skeleton supporting action of the cellulose nanocrystal. The method for preparing the cellulose nanocrystal hydrophobic porous powder is environmentally friendly, economical and efficient.