20 results about "Diels alder" patented technology

The application discloses application of a divinyl tetrazine in cyclization of a linear polypeptide, and a structure formula of the divinyl tetrazine is; the linear polypeptide has at least two free mercapto groups, and the vinyl groups of the divinyl tetrazine are subjected to Michael addition reaction with corresponding mercapto groups to form a ring. The application provides a new use of the divinyl tetrazine, the divinyl tetrazine can be subjected to high-efficiency Michael addition reaction with two natural cysteine mercapto groups on the linear polypeptide through the vinyl groups, so that double-mercapto peg cyclization of the linear polypeptide is realized, and the purpose of limiting the conformation of the linear polypeptide and improving the stability of the linear polypeptide is achieved. Moreover, the divinyl tetrazine can be subjected to a reverse electron demand Diels-Alder reaction with trans-cyclooctene (TCO) after the two vinyl groups are subjected to reaction with mercapto groups, so that functional polypeptides can be modularly constructed by coupling with functional molecules modified with TCO, and related applications are realized.

The invention relates to the technical field of polymer functional materials, and discloses a novel base plate and a processing technology thereof.The base material of the base plate is composed of furan functionalized polyurethane and bismaleimide which are cross-linked through a reversible Diels-Alder reaction, and a formed dynamic covalent network enables the base plate to have the thermally-induced self-repairing capacity; latent temperature-sensitive dye and latent photoluminescence molecules are uniformly dispersed in the matrix at the same time. The processing technology comprises the steps that the components are subjected to melt blending and compression molding to form a base plate biscuit, then ultraviolet light with the specific wavelength is used for selectively irradiating a preset area of the biscuit, and functional writing is completed. In the illumination step, latent functional molecules are activated in situ in the material, so that irreversible chemical structure transformation occurs on the latent functional molecules, and therefore, the high-wear-resistance embedded identifier with temperature-sensitive warning and light-induced verification functions is formed. The technical problems that a traditional base plate mark is prone to abrasion, single in function and incapable of being repaired after being damaged are solved.

The invention relates to a transparent dynamic covalent cross-linked polyurethane plate capable of being processed and remolded and a preparation method of the transparent dynamic covalent cross-linked polyurethane plate. The transparent dynamic covalent cross-linked polyurethane plate comprises the following raw material components: polyisocyanate, a polyol chain extender, a functional cross-linking agent, a solvent and a catalyst, the plate structurally comprises at least one of boric acid ester with a thermal stimulation response function, Diels-Alder reaction, thiocarbamate bonds, oxime urethane bonds, disulfide bonds, imine bonds and carbamate bonds. According to the invention, dynamic covalent bonds with thermal response characteristics are introduced into cross-linking points, and the cross-linked polyurethane plate with high transparency, high mechanical strength and reversible processability is constructed through interaction and synergy with rich hydrogen bonds in polyurethane.

The invention belongs to the technical field of polymer insulating materials, and particularly discloses an insulating paint composition, a preparation method thereof and application of an enameled wire. The insulating paint composition comprises the following components in parts by weight: 100 parts of polymer resin, 5-10 parts of microcapsules, 15-35 parts of auxiliaries and a solvent, the core material of the microcapsule is Lewis acid, and the wall material of the microcapsule is polyurea formaldehyde or polyurethane. And the polymer resin is a polyester or polyamide-imide of which the tail end is grafted with a Diels-Alder adduct. A paint film formed by the composition disclosed by the invention can keep the stability of a cross-linked network during high-temperature working, and can activate the recombination of Diels-Alder dynamic bonds under the mild condition of relatively low damage to the paint film when the paint film needs to be repaired; and the structural stability in a high-temperature working environment and the repairability under a mild condition after damage can be realized at the same time.

A resin composition for forming a structural element such as a flooring panel includes a resin system including: 45-60 wt % of a plant-derived polyfurfuryl alcohol resin; up to 15 wt % of a non-structural filler such as talc or jute fibre; and 35-40 wt % of a glass fibre. 5 A method of making the structural element includes mixing the resin and filler to produce the resin system; laying up multiple layers of the resin system and the glass fibre in a mould; subjecting the mould to an initial heating profile in an initial resin curing step so that the resin system undergoes a condensation reaction and such that substantially all of the water produced in the condensation reaction has been removed, wherein the heating profile comprises a first, an intermediate, and a final temperature. The product is subsequently subjected to a post-curing step comprising a Diels-Alder reaction.

The invention belongs to the technical field of petroleum resin preparation, and relates to a preparation method of hydrogenated petroleum resin based on D-A reaction toughening. Specifically, conjugated diene and a dienophile are subjected to a Diels-Alder reaction to generate a prepolymer monomer with a cyclohexene structure, cationic polymerization of the prepolymer is initiated under catalysis of a Lewis acid catalyst, a molecular chain is further increased, a D-A polymer with higher molecular weight and a specific branched structure is obtained, and deep hydrogenation is performed to obtain the high-molecular-weight and high-molecular-weight D-A polymer with a specific branched structure. The fully saturated hydrogenated petroleum resin with a rigid alicyclic structure and a flexible ester group side chain is obtained. The hydrogenated petroleum resin has good thermodynamic properties, mechanical properties and aging resistance which are synergistically optimized, meets the technical requirements of high polymer material additives, and has remarkable strategic development potential and market competitiveness in the field of refined, functionalized and green chemical materials.

To provide a resin of at least one of an aromatic polycarbonate and a polyarylate having a new structure, which does not contain a radical initiator, a reaction catalyst or the like causing deterioration of electric characteristics, further can be produced without using UV, an electron beam or the like deteriorating a charge transport material (CTM), and does not substantially contain a polymer of only a single component when there are multiple polymerizable components.SOLUTION: A resin is at least one resin selected from a group consisting of an aromatic polycarbonate and a polyarylate, in which the resin has a bond between polymer chains due to a Diels-Alder reaction.SELECTED DRAWING: None

The application belongs to the technical field of organic synthesis, and particularly relates to a preparation method of a chiral dihydroquinolone compound. The application utilizes N-heterocyclic carbene (NHC) as a catalyst, and generates the chiral dihydroquinolone through a nitrogen hetero-diene Diels-Alder reaction of a chloroaldehyde and an azo-ortho-benzoquinone precursor under the action of NHC and an alkaline reagent. The preparation method of the application does not need to use a transition metal as a catalyst, can perform a reaction under relatively mild conditions, and has the advantages of green environmental protection, low cost, wide substrate selectivity, mild reaction conditions and the like. In addition, by optimizing the reaction conditions of the preparation method, the product has high yield, high purity, unique cis selectivity and excellent enantioselectivity. The application provides a new route and new idea for the chiral dihydroquinolone compound, can play an important role in the fields of drug intermediates and the like, and has good application value and potential.

The invention belongs to the technical field of material science and functional polymer materials, and particularly relates to a preparation method of a puncture-resistant aerogel heat-sealing film with a self-repairing function, which comprises the following steps: constructing a polyvinylpyrrolidone nanofiber sacrificial template through electrostatic spinning; generating a silicon dioxide aerogel network by an in-situ sol-gel method; removing the template through solvent extraction to obtain a continuous aerogel skeleton; introducing a furanized polyurethane and maleimide cross-linking agent precursor solution through vacuum infiltration; thermally initiating Diels-Alder reaction to form a dynamic covalent bond cross-linked polymer network; and finally carrying out hot-press molding. By the adoption of the technical scheme, collaborative optimization of heat insulation performance and mechanical performance can be achieved, the film is endowed with excellent puncture resistance and a heat triggering self-repairing function, and meanwhile the film has good heat sealing processability.

The invention relates to a method for providing pyridazines by fast oxidation of dihydropyridazines. The pyridazines can be used in treatments such as radiotherapy, diagnostics, imaging and other photochemical methods. The method is suitable for dihydropyridazine mixtures generated by a click reaction between a first chemical entity which is a 1,2,4,5-tetrazine or a strained alkene with retro Diels-Alder cycloaddition reactivity and a second chemical entity which is a 1,2,4,5-tetrazine or a strained alkene with complementary retro Diels-Alder cycloaddition reactivity. The linkage between the first chemical entity and the second chemical entity is followed by fast acid catalyzed oxidation.

Described herein is a dual-functional tetrazine–allyl reagent that enables site-selective disulfide modification in peptides and proteins, serving both as a Michael acceptor for bis-thiols and as a reactive handle for Inverse Electron-Demand Diels–Alder (IEDDA) click chemistry to introduce functional payloads.

The invention provides an industrial production method of high-purity methyl nadic anhydride, and belongs to the technical field of organic chemical synthesis and fine chemical engineering. In order to solve the problems of low product purity and unstable yield caused by impure raw materials, the method comprises the following steps: carrying out pretreatment purification on a methylcyclopentadiene dimer raw material, including thermal depolymerization, rapid cooling and rectification separation, so as to obtain a high-purity methylcyclopentadiene monomer; dissolving maleic anhydride in an inert solvent, then adding the monomer, and carrying out Diels-Alder addition reaction to obtain a crude product; and rectifying and purifying the crude product to obtain the high-purity methyl nadic anhydride. According to the invention, the high-purity product can be stably obtained, the material recycling is realized, the production efficiency is improved, and the cost is reduced.

A resin composition for forming a structural element, such as a floor panel, comprises a resin system comprising: 45-60% by weight of a polyfurfuryl alcohol resin of plant origin; up to 15% by weight of a non-structural filler such as talc fibers or jute fibers; and 35 to 40 wt% of glass fibers. A method of making the structural element comprises: mixing the resin and a filler to produce the resin system; laying a plurality of layers of the resin system and the glass fibers in a mold; in an initial resin curing step, the mold is subjected to an initial heating profile such that the resin system undergoes a condensation reaction and such that substantially all of the water generated in the condensation reaction is removed, where the heating profile comprises a first temperature, an intermediate temperature and a final temperature. The product is then subjected to a post-curing step including a Diels-Alder reaction.

The invention discloses a near-infrared two-region aza-BODIPY photosensitizer capable of reversibly capturing and releasing singlet oxygen as well as a preparation method and application of the near-infrared two-region aza-BODIPY photosensitizer. According to the photosensitizer, a singlet oxygen carrier (2-pyridone, anthracene or 1, 4-dimethylnaphthalene) is used as a response unit, a triphenylamine-thiophene group is used as an electron donor, and an aza-BODIPY mother nucleus structure is modified. Wherein the singlet oxygen carrier can capture singlet oxygen generated by illumination through [4 + 2] cycloaddition reaction to generate endoperoxide; the latter releases singlet oxygen again through a reverse Diels-Alder reaction in a dark environment. A nano diagnosis and treatment agent constructed by self-assembly of the photosensitizer and distearoyl phosphatidyl ethanolamine-polyethylene glycol 2000 through a nano precipitation method can capture singlet oxygen at a tumor site and release singlet oxygen for a long time under a dark condition under the irradiation of 808 nm laser; the technical bottlenecks that singlet oxygen is short in service life in a tumor microenvironment and needs a light source to continuously irradiate a photosensitizer are effectively overcome, and a new strategy is provided for enhancing the depth and curative effect of photodynamic therapy.

A method for producing a biaryl compound, including the steps of: generating a benzyne compound from a precursor of the benzyne compound; generating a fused ring compound containing a 1,4-epoxy-1,4-dihydrobenzene ring by subjecting the benzyne compound and a furan compound to a Diels-Alder reaction; and generating a biaryl compound by subjecting the fused ring compound and a halogenated aryl compound to a cross-coupling reaction.

The application relates to a nanocomposite eucommia rubber shape memory material and a preparation method thereof, and belongs to the technical field of high polymer materials. The application aims to solve the technical problems of insufficient shape memory performance of the existing eucommia rubber-based material, easy agglomeration of nanofillers and weak interface combination. X The application is prepared by the following steps: mixing a chemically modified Ti3C2T X with eucommia rubber and a plasticizer to prepare nanocomposite masterbatch, dynamically vulcanizing the nanocomposite masterbatch with a bismaleimide dynamic covalent crosslinking agent at 125-135 DEG C to construct a Diels Alder reversible topological crosslinking network, and finally performing mold forming to obtain the nanocomposite eucommia rubber shape memory material. The obtained material has the balance of strength and toughness, the shape fixing rate is greater than or equal to 97.8%, the recovery rate is greater than or equal to 96.5%, the thermal response recovery time is less than or equal to 10 seconds, the self-repairing efficiency is more than 70%, and the material has repeatable processability.

A debondable adhesive formulation comprising a multifunctional polymer having programmable bonds made from a Diels-Alder adduct and a concentration of a diene trapping agent. The programmable bonds include one or more diene-dienophile pairs capable of forming a Diels-Alder adduct. The debondable adhesive formulation can be applied as a coating. The debondable adhesive formulation can be extruded. The debondable adhesive formulation has a bonding temperature of 30°C to 150°C and a debonding temperature of 130°C or greater. When the debondable adhesive formulation is at or above the debonding temperature, at least a portion of one or both of the programmable bonds and the diene-diene trapping adduct dissociate and the adhesive bond strength is reduced. The adhesive formulation includes non-programmable bonds that do not dissociate at the debonding temperature.

The invention belongs to the technical field of casting materials, and relates to novel anti-sintering precoated sand and a preparation method thereof. The precoated sand comprises the following components in parts by weight: 90 to 97 parts of synergistically modified quartz sand, 1.5 to 3.5 parts of phenolic resin, 0.1 to 1.0 part of 9, 9-bis (4-hydroxyphenyl) fluorene, 0.2 to 0.8 part of hexamethylenetetramine, 0.1 to 0.5 part of calcium stearate and 0.2 to 1.5 parts of iron oxide red. Wherein the synergetic modified quartz sand forms a multi-network synergetic interface structure by sequentially constructing a silicon-oxygen bond anchoring structure, a Diels-Alder reversible covalent thermal response network structure and a phosphorus-containing ceramic interface layer on the surface of the quartz sand. The 9, 9-bis (4-hydroxyphenyl) fluorene is used as a high-rigidity small organic molecule function regulating agent, so that the carbonization compactness and the interface barrier ability are improved. High-temperature sintering bridging and sand burning behaviors are inhibited through intrinsic regulation and control of an interface structure, the sintering area and the sand burning rate are remarkably reduced, meanwhile, the shell mold strength and the high-temperature carbon residue rate are improved, and the method is suitable for the field of high-end precision casting.

The invention discloses a graphene modified marine anticorrosive paint based on dynamic covalent bonds, which takes a reversible cross-linked network as a core, and is prepared by the following steps: firstly, synthesizing two dynamic reaction precursors of furan functionalized methyl vinyl MQ type silicon resin and maleimide functionalized graphene oxide; then the furan group and the maleimide group are uniformly dispersed in a solvent and coated on the surface of a base material, a Diels-Alder cycloaddition reaction between the furan group and the maleimide group is triggered through heating, and a three-dimensional dynamic covalent cross-linked network is constructed in situ in the coating. According to the dynamic cross-linked structure, the interface bonding force of graphene and silicon resin is remarkably enhanced in a chemical bonding mode, filler agglomeration is avoided, the physical shielding and mechanical enhancement effects of graphene are fully exerted, the overall coating is endowed with excellent toughness, impact resistance and permeability resistance, and the service life of the coating is prolonged. And cavitation erosion in the marine environment can be effectively resisted, and the synergistic effect of scouring and corrosive media can be effectively resisted, so that long-acting and reliable anti-corrosion protection is realized.

The present invention relates to maleic acid derivatives polar group-containing polypropylene, the process to making the same by reactive extrusion in presence of a grafting agent, a polypropylene co- and / or homopolymer is put in contact with a Diels-Alder adduct which is the reaction product of a diene and a dienophile belonging to the group of maleic acid derivatives.