96results about How to "Improve self-healing efficiency" patented technology

The invention relates to the field of new materials, in particular to a self-repairing reprocessable polyurea material as well as a preparation method and application. The self-repairing reprocessablepolyurea material comprises the following raw materials in parts by weight: 3 to 13 parts of a cross-linking agent, 79 parts of amino-terminated polyetheramine, 8 to 18 parts of diisocyanate, and 1 to 5 parts of a catalyst. The polyurea material is obtained by reacting an amino group with isocyanate, and is a novel heat-responsive dynamic bond under the action of high temperature or the catalyst,so that the material can be self-repaired at 80 DEG C, and the interaction of hydrogen bonds between urea bonds can improve the mechanical strength of the material; and the polyurea material is excellent in mechanical properties, endowed with certain transparency, good in reworking properties, high in self-repairing efficiency, relatively low in repair temperature, simple in preparation technology, and low in relative cost.

The invention provides a a design strategy of a novel adhesive hydrogel material and obtains a high-extension, self-healing, and high-adhesion biocompatible hydrogel material. Based on a double network structure design principle, polymerizable polyethylene glycol-based high polymer constitutes a first covalent crosslinked network, and hydrophilic high polymer with ultra-high molecular weight forms a second noncovalent crosslinked network through entanglement. A mesh size of a first network is larger than a molecular effective size of second network high polymer, and molecular weigh of high polymer forming a second network should be larger than a critical entanglement molecular weight thereof, so that effective molecular entanglement is formed, high-extension, self-healing, and high-adhesion characteristics are given to double network hydrogel. The novel hydrogel can rapidly and repeatedly form stable adhesion with surfaces of various materials. Damaged by an external force, the hydrogel can rapidly and repeatedly perform self healing. The material can be used as a cell cultivating carrier, a sewing-free novel dressing, and can be applied to wearble sensors.

On the basis of the current situation of self-repairing polyurethane materials, the invention provides an aromatic terminal hydroxyl chain extender containing an acylhydrazone bond, self-repairing polyurethane prepared by using the aromatic terminal hydroxyl chain extender and a preparation method of the self-repairing polyurethane. Compared with dihydric alcohol containing an acylhydrazone bond, the aromatic terminal hydroxyl chain extender containing the acylhydrazone bond has the advantages that the molecular structure of the aromatic terminal hydroxyl chain extender has the large pi bond of a hydrazide benzene ring and the pi-pi conjugative effect of the pi bond of carbon-oxygen double bonds, and accordingly the chain extender is stable in structure. The prepared self-repairing polyurethane has the advantages that the molecular chain of the polyurethane contains the reversible acylhydrazone bond, can achieve self-repairing under room temperature, and is high in repairing efficiency and good in mechanical performance. The preparation of the self-repairing polyurethane has the advantages that the method is simple, raw materials are products which are commercially produced, and the prepared polyurethane is high in performance controllability and promising in application prospect.

The invention discloses a self-repairing microcapsule used for a metal anticorrosion coating and a preparation method thereof, which belong to the technical field of self-repairing materials. The wall material of the self-repairing microcapsule is urea resin, the core material of the self-repairing microcapsule is natural plant oil, and the self-repairing microcapsule is prepared with a one-step in-situ polymerization method. The natural plant oil has the advantages of wide source and low cost and is easy to obtain. The metal anticorrosion coating is coated on the surface of metal to form an anticorrosion coating. Microcracks appear in the long-term use process, the self-repairing microcapsule embedded in the coating is broken by external force, and released natural plant oil and oxygen in the air can directly generate crosslinking polymerization reaction without catalysts to repair the microcracks to prevent the surface of the metal from being further corroded. The self-repairing microcapsule synthetized by the core material substance has the advantages of good mechanical performance, simple preparation technology and low cost and can be widely applied to the self repairing of metal anticorrosion coatings, such as automobile industry, ship industry and the like.

The invention discloses a reversible self-repair antibacterial acrylic coating and preparation and self-repair methods. The preparation method comprises the steps of adding methyl methacrylate, butyl acrylate, sulfonyl betaine methacrylate and acetoacetoxy methacrylate gylcol ester into an alcohol solvent, and performing free radical polymerization under the initiation of azodiisobutyronitrile to obtain linear acrylic resin; and dissolving the linear acrylic resin and amino-containing hyperbranched polysiloxane into the alcohol solvent, coating the surface of a base material, and drying, thus obtaining the reversible self-repair antibacterial acrylic coating. Efficient and mild repair of the coating is realized by using the characteristic of reversible reaction of vinylogous urethane bonds at room temperature and amino rich at the terminal of the hyperbranched polysiloxane, and the acrylic coating is endowed with excellent antibacterial property by the safe, nontoxic and non-specific sulfonyl betaine. The product has good applicability and strong practicability; the preparation method has the characteristics of wide raw material source, simple process and environment friendliness.

The invention discloses a preparation method of waterborne flame-retardant self-repairing polyurethane based on modified graphene. The method comprises the following steps: firstly, ultrasonically crushing amino cyclotriphosphazene and isocyanate silane covalently modified graphene oxide, then reacting with macromolecular diol, a hydrophilic chain extender and diisocyanate, terminating with diselenide diol, neutralizing, emulsifying, and adding waterborne self-repairing polyurethane containing diselenide bonds so as to obtain the waterborne flame-retardant self-repairing polyurethane emulsion. According to the invention, by reducing the size of graphene oxide and modifying a waterborne polyurethane chain, the water dispersion stability and the dispersion uniformity and compatibility of the graphene oxide in the membrane are improved, so that the mechanical strength of the membrane is improved; due to nitrogen phosphorus silicon modification, the flame retardant property is further improved; the material is endowed with a good room-temperature illumination self-repairing function through double selenium bonds; and the method provided by the invention is environment-friendly, and the prepared material has high mechanical property and excellent flame-retardant self-repairing function, and can be applied to various fields of leather finishing, fabric finishing and the like.

The invention relates to a preparation method of a fluorinated polyurethane coating and a super-hydrophobic coating, and the method comprises the following steps: preparing a mercaptan prepolymer witha long fluoroalkane chain, and inoculating the fluoromercaptan prepolymer into a polyurethane prepolymer through a simple polyurethane reaction to obtain the fluorinated polyurethane coating; blending and dispersing nanoparticles and the fluorinated polyurethane coating according to a certain ratio, spraying, brushing or impregnating the mixture on the surface of a base material, and after a solvent is completely volatilized, putting the coating in a 70 DEG C drying oven for heat treatment for 5 hours to obtain the super-hydrophobic coating. The coating has high abrasion resistance, and afterthe coating is completely damaged, the super-hydrophobic performance of the coating can be recovered to a large extent within a short time through heating.

The invention relates to a method for improving self-healing of a cold-mix asphalt mixture based on nano carbon fibers, and belongs to the technical field of road repair. The problems that an existingmicrocapsule self-healing technology and electromagnetic induction heating technology are large in limitation, conditions are severe, the research on self-healing of the cold-mix asphalt mixture is not realized by using a microwave heating technology, and the research on using nano carbon fibers and PCL as fillers is not carried out are solved. The method comprises the steps that SBS modified emulsified asphalt is prepared at first, then the modified emulsified asphalt is mized with carbon nanofibers, PCL and the like at room temperature to prepare the cold-mix asphalt mixture, a joist test piece is prepared, a damaged test piece is obtained by using a four-point bending fatigue test, cracks are marked, and finally microwave heating equipment is used for heating the damaged test piece tobe higher than the softening point by 10 DEG C for 30 minutes; and fatigue test is carried out again on the damaged test piece subjected to self-healing and curing to determine the self-healing rate of the test piece so as to determine the optimal mixing amount of the nano carbon fibers. The cold-mix asphalt mixture prepared by the method can improve the self-healing capability of an asphalt pavement.

The invention provides a graphene functional self-repairing microcapsule with a cellular structure and a preparation method thereof, aiming at the problems in a self-repairing system in the prior art,The internal repairing and external fixing graphene functional self-repairing microcapsule with the cellular structure consists of a capsule wall and a curing agent with which the capsule wall is covered, wherein graphene is dispersed in the capsule wall; a series of microcapsules of a micro-nano scale are dispersed in the curing agent to form a cellular structure; the insides of the microcapsules of the micro-nano scale are covered with a repairing agent. The self-repairing microcapsule system has a multi-core coating structure of a micro-nano scale, thereby improving the stability of the microcapsules, increasing the probability of contact between the repairing agent and the curing agent at the same time, and improving the repairing efficiency. In addition, the capsule wall of the self-repairing microcapsule system is modified by silane, an unhydrolyzed silane emulsion left after rupture of the microcapsules can form a hydrophobic film inside concrete capillary holes to prevent further diffusion of moisture, and the hydrolyzed silane emulsion can also participate in the synthesis of a wall material to improve the performance of the microcapsules.

The invention belongs to the field of rubber, and particularly relates to self-repairing rubber. The self-repairing rubber comprises the following components in parts by weight: 60-120 parts of butylrubber, 140-160 parts of polyisobutene, 5-15 parts of an additive, 0.1-0.5 part of sulfur and 0.1-0.2 part of a sulfur accelerator. According to the method, the self-repairing efficiency of the rubbercan be effectively improved, and the damaged part can be repaired within a plurality of seconds; the puncture-proof capacity is high, and under the condition that the puncture depth is far larger than the material thickness by 200%, the rubber can still be prevented from being punctured; in addition, the preparation method is simple and efficient and low in energy consumption.

The invention relates to a preparation method and an application method of porous boron nitride nanofiber/polyvinyl alcohol composite hydrogel. The preparation method comprises the following steps: adding porous BNNFs into deionized water to obtain a dispersion liquid; and adding PVA into the dispersion liquid, conducting heating and stirring in a water bath at 90-100 DEG C for 2-4 hours, and naturally cooling the sol obtained after heat preservation to room temperature, thereby obtaining the porous boron nitride nanofiber/polyvinyl alcohol composite hydrogel with favorable self-healing property. The hydrogel obtained by the invention can be retreated by a short-time freeze thawing method, so the mechanical properties of the hydrogel are enhanced, and the hydrogel can be used in the fieldsof biomedicine, wearable flexible electronic devices and the like, and has higher safety usability compared with hydrogel prepared by polymerizing monomolecules via a chemical cross-linking agent.

The invention belongs to the technical field of novel materials, in particular to a preparation method and application of a silicone rubber film with underwater self-healing capability and adhesiveness. Terephthalaldehyde, isoflurone diisocyanate, tris(2-aminoethyl)amine, 4,4'-diaminodiphenyl disulfide and bis(3-aminopropyl) terminated poly(dimethylsiloxane) are taken as raw materials, and a polycondensation reaction is carried out to form a triple reversible crosslinking network with imine bonds, hydrogen bonds and disulfide bonds. The silicone rubber prepared by the reaction has good mechanical properties, rapid underwater self-healing properties, and excellent adhesion properties and hydrophobicity. The self-healing silicone rubber disclosed by the invention is simple in preparation method and wide in raw material source; and various excellent properties of the self-healing silicone rubber can be used for self-healing waterproof leakage-proof coatings, self-healing waterproof adhesive tapes, protective layers of fragile materials and the like. The viscous self-healing silicone rubber has wide application prospects in the fields of flexible robots and the like.

The invention provides a graphene functionalization self-repairing microcapsule with a cellular structure and a preparation method of the self-repairing microcapsule for the problem existing in a self-repairing system in the prior art. The outer-repairing and inner-curing type graphene functionalization self-repairing microcapsule comprises a capsule wall and a repairing agent coated by the capsule wall, wherein graphene is dispersed in the capsule wall; a series of micro-nano microcapsules are dispersed into the repairing agent, so as to form a cellular structure; a curing agent is coated ineach of the micro-nano microcapsules. The self-repairing microcapsule system has a micro-nano multinuclear coating structure, so that the stability of the microcapsule is enhanced, meanwhile, the contact probability of the repairing agent and the curing agent are increased, and the repairing efficiency is improved. Additionally, the capsule wall of the self-repairing microcapsule system is modified by silane, silane emulsion which is not hydrolysed after the microcapsule is ruptured can form a hydrophobic membrane in a capillary hole of concrete, and the water content can be prevented from being diffused further; in addition, silane emulsion which is hydrolysed can participate in the synthesis of a wall material, so that the property of the microcapsule is improved.

The invention belongs to the technical field of concrete, and particularly relates to a composite concrete self-repairing material and application thereof, and a preparation method of self-repairing concrete. According to the invention, calcium and magnesium ions provided by a mineral admixture and carbonate provided by lightweight aggregate increase the concentration of calcium, magnesium ions and carbonate ions at concrete cracks, so generation of calcium carbonate, magnesium hydroxide and magnesium carbonate is facilitated; and water can be taken away and released under a high-humidity condition due to the swelling capacity of water-absorbent resin, and the water is used for supplementing water needed in the forming process of calcium carbonate, magnesium hydroxide and magnesium carbonate and accelerating generation of new C-S-H crystals, so finally, concrete crack closing is promoted, and self-healing efficiency is improved.

The invention discloses a flame-retardant self-repairing waterborne polyurethane composite coating agent as well as a preparation method and application thereof, and belongs to the technical field of production of coating agents. The method comprises the following steps: reacting nano particles with a coupling agent to prepare aminated nano particles; enabling the aminated nano particles to react with phosphonitrilic chloride trimer and diamine, so as to prepare amino-terminated hyperbranched polyphosphazene modified nano particles (HBPC); then mixing polyester glycol, a hydrophilic monomer and diisocyanate to react, so as to prepare an isocyanate group-terminated prepolymer solution; a dynamic reversible covalent bond monomer, a dynamic reversible non-covalent bond monomer and HBPC are added into the prepolymer solution for a reaction, and a chain extension product solution is prepared; and adding a neutralizing agent into the chain extension product solution for reaction to prepare the HBPC waterborne polyurethane with flame-retardant and self-repairing functions. The prepared flame-retardant self-repairing waterborne polyurethane composite coating agent has a hyperbranched and double reversible bond structure, can realize quick and efficient self-repairing at high temperature, and can be applied to flame-retardant self-repairing coatings of wood lacquer.