319 results about "Diels alder" patented technology

The invention discloses a dynamic bond-containing polyurethane material for 3D printing and its preparation method and use. The preparation method utilizes, by mole, 100 parts of diisocyanate, 50-75 parts of polyester polyol or polyether polyol, 50-125 parts of a Diels-Alder bond-containing dihydric alcohol chain extender, 0-50 parts of a diisocyanate trimer cross-linking agent, 50-100 parts of a ligand-containing dihydric alcohol chain extender and 0-50 parts of a metal salt cross-linking agent. The Diels-Alder bond-containing dihydric alcohol chain extender and the diisocyanate trimer cross-linking agent are matched and are used for preparation of a Diels-Alder bond-containing polyurethane material. The ligand-containing dihydric alcohol chain extender and the metal salt cross-linking agent are matched and are used for preparation of a metal ligand-containing polyurethane material. Molecular structures of the prepared polyurethane materials contain a dynamic medical bond Diels-Alder bond and a metal ligand bond. The Diels-Alder bond-containing or metal ligand-containing polyurethane material has functions of self-restoration and self-bonding.

The present invention provides a method for the covalent immobilization of biomolecules on polymers for delivery of the biomolecules, which has the advantage of being simple, highly efficient, environmentally friendly and free of side products relative to traditional immobilization techniques. The invention provides a modified micro/nanoparticle system, which uses a functionalized polymer formed into micro or nanoparticles to bind a molecule to the particles using uses facile chemistry, the Diels-Alder cycloaddition between a diene and a dienophile with the polymer being functionalized with one of them and the molecule with the other, or the Huisgen 1,3-dipolar cycloaddition between a terminal alkyne and an azide to bind the molecule to the particle. The molecules and/or other therapeutic agents may be encapsulated within the polymer particles for intravenous therapeutic delivery. The invention also provides a novel synthetic biodegradable polymer, a furan/alkyne-functionalized poly(trimethylene carbonate) (PTMC)-based polymer, whose composition can be designed to meet the defined physical and chemical property requirements. In one example, the particle system self-aggregates from functionalized PTMC-based copolymers containing poly(ethylene glycol) (PEG) segments. The composition of the copolymers can be designed to meet various particle system requirements, including size, thermodynamic stability, surface PEG density, drug encapsulation capacity and biomolecule immobilization capacity.

The invention provides novel siloxane monomers useful in a variety of adhesive applications. In one aspect, the siloxane compounds described herein can be used as Diels-Alder type curatives for bismaleimide or poly-maleimide monomers. The unsaturated resins shown here are attractive for use as maleimide curatives due to their poly-functionality. Each substituted styrenyl reside can react with two maleimide functional groups. Thus, an invention adhesive composition typically contains an excess of bismaleimide monomers.

The invention relates to the use of a powder made of a polymer, which of two or more components with functionalities suitable for Diels-Alder reactions, or of a powder mixture (dry blend) made of powders respectively of at least one of the reactive components, where these together enter into the Diels-Alder reaction with one another and are capable of a retro-Diels-Alder reaction, in a rapid-prototyping process.

The invention further relates to moldings produced with use of said polymer powder through a layer-by-layer shaping process in which regions of a powder layer are melted selectively. The molding here can be removed from the powder bed after cooling and hardening of the regions previously melted layer-by-layer.

The invention discloses a self-repairing polyurethane nano-composite material and a preparation method and application thereof. The preparation method comprises the following steps: firstly, adding a surfactant and a conductive nano-filler into excessive absolute ethanol to obtain dispersion liquid containing the conductive nano-filler; then, adding a prepared self-repairing polyurethane powder material containing a Diels-Alder bond into the dispersion liquid, and performing suction filtration and drying to obtain a polyurethane powder material which is coated with the conducive nano-filler and contains the Diels-Alder bond; lastly, performing machine shaping to obtain a Diels-Alder bond-based multiple self-repairing polyurethane nano-composite material. The self-repairing polyurethane nano-composite material prepared by the method has the advantages that: (1) the material has excellent mechanical performance, excellent electric performance, an excellent photothermal effect and an excellent electromagnetic effect; (2) the material has excellent self-repairing performance; (3) the material has a plurality of repairing manners; (4) in a power-on state, sensing of cracking of the material can be realized, and self-repairing is performed.

A Diels-Alder adduct of a trans-cyclooctene with a tetrazine is provided, wherein the adduct bears a substituent labeled with a radionuclide. A method of producing a PET or other image of an organ in an animal or human includes forming the Diels-Alder adduct in the animal or human. Trans-cyclooctenes and tetrazines suitable for preparing the adducts are provided.

The invention relates to reprocessed polyurethane with dual-dynamic covalent bond crosslinking and a preparation method of the reprocessed polyurethane, and belongs to the field of high-molecular materials. Diisocyanate, triisocyanate or tetraisocyanate, macromolecular polyol/amine and dihydric alcohol/amine chain extenders with dynamically reversible Diels-Alder bonds and disulfide bonds are melted and commixed under the action of a catalyst or polymerized after addition of solvent to obtain the reprocessed polyurethane. Dual-dynamic bonds are introduced, so that the requirements of materials for mechanical properties are met, the materials have excellent reprocessing and self-repairing properties in different application environments, and the chain extenders with dynamically reversible Diels-Alder bonds and disulfide bonds can fracture and recombine at a certain temperature, so that the polyurethane materials have reprocessing performance and self-repairing functions on cracks or damage generated in the use process. Material viscosity obviously reduces after the dynamic bonds fracture, and melt viscosity is remarkably improved, so that processing performance is improved.

The invention discloses a reversible covalent cross-linked epoxy resin. The reaction between diene monoamine and an epoxy resin monomer is adopted for obtaining a linear epoxy resin with a diene on a side chain, the linear epoxy resin and a dienophile cross-linking agent form a Diels-Alder reversible reaction cross-linked point on the side chain, the reversible covalent cross-linked bond of the cross-linked epoxy resin breaks at a temperature of 100 to 150 DEG C, and can be restored again when the temperature is lowered to below 90 DEG C, so that the crosslink reversibility can be achieved. The reversible covalent cross-linked epoxy resin and the preparation method, provided by the invention, have the advantages that: (1), the reversible covalent cross-linked point is introduced to the side chain of the linear epoxy resin, so that the thermostability, solvent corrosion resistance and mechanical property of the material are improved, and by changing the cross-linking density, the material performance can be adjusted within a larger range; (2), both structures of the diene and the dienophile in the cross-linked epoxy resin have reversible reaction properties, so that recycling and reprocessing under certain conditions can be conducted; (3), the preparation method is simple and convenient, and is easy to implement, the relative cost is low, and raw material sources are wide.

The invention discloses a reversible repair functional matrix resin for pultrusion and a preparation method of the matrix resin. The matrix resin is prepared from the following raw materials in parts by weight: 30-60 parts of 4,4'-diallylbisphenol A diglycidyl ether epoxy resin, 20-35 parts of furfuryl amine, 15-30 parts of 4,4'-bismaleimide diphenylmethane, 0-25 parts of liquid epoxy resin and 5-15 parts of curing agent. The preparation method comprises the following steps: dissolving the 4,4'-diallylbisphenol A diglycidyl ether epoxy resin in a formula amount into a solvent, slowly adding the furfuryl amine into a reaction container for reacting, adding the 4,4'-bismaleimide diphenylmethane, liquid epoxy resin and curing agent, reacting and mixing for a hour, performing reduced pressure distillation to remove the solvent, and cooling. The reversible repair functional matrix resin for pultrusion and the preparation method of the matrix resin disclosed by the invention have the beneficial effects that the matrix resin has good molding manufacturability, the molecular structure contains furan and imide structures, the heating and repairing functions of the prepared composite material can be realized by virtue of a Diels-Alder reversible reaction, and the matrix resin also has the advantages of high strength and high heat resistance.

The invention discloses a reversible covalent crosslinked polyurethane and epoxy resin composite comprising two components: linear polyurethane and linear epoxy resin, wherein side chains of the reversible covalent crosslinked polyurethane and epoxy resin composite are respectively provided with a dienophile functional group and a diene functional group; the composite is a material with a crosslinked network structure, which is formed by connecting linear polyurethane and linear epoxy resin through a Diels-Alder reversible covalent bond; the Diels-Alder reversible covalent bond can be reversibly broken and bonded through temperature adjustment, so that the composite conversion between a linear polymer and the material with the crosslinked network structure has the characteristic of reversible covalent crosslinking. The reversible covalent crosslinked polyurethane and epoxy resin composite has the advantages that the mechanical and thermodynamic properties are excellent, and the mechanics can be adjusted within a relatively wide range; the preparation method is simple, convenient and controllable, the reversible covalent crosslinked polyurethane and epoxy resin composite is high in yield, good in quality and wide in application range, and the performance of the composite can be optimized through being re-modified by using filler.

The invention discloses a group of novel and functionalized arylene polymers that comprise repeat units from a group consisting of polyarylene, polybenzimidazolene, polybenzimidazole, and poly(arylene-co-cyclohexadiene). The compositions are created via Diels-Alder polymerization and result in a polymer that is chemically and thermally stable. The polyarylene polymers can be used to create improved polymer electrolyte membranes that overcome the limitations of Nafion® membranes for use in fuel cells.

The invention provides a Diels-Alder bond containing self-repairing flame retardant polyurethane elastomer and a preparation method of the Diels-Alder bond containing self-repairing flame retardant polyurethane elastomer. The structural formula of the polyurethane elastomer is shown in the specification. The preparation method of the polyurethane elastomer is as follows: (1) preparing dihydric alcohol having a furan functional group; (2) preparing a linear-structure polyurethane solution comprising a furan functional group on a side chain; (3) preparing a maleimide modified phosphonitrilic chloride trimer flame retardant; and (4) preparing the Diels-Alder bond containing self-repairing flame retardant polyurethane elastomer.

The invention belongs to the field of a UV (Ultraviolet) photocatalysis biomass chemical reaction and in particular discloses a preparation method and an application of a UV photocatalysis-based unsaturated vegetable oil Diels-Alder (D-A) reaction product. The preparation method comprises the steps of: preparing vegetable oleate with unsaturated natural vegetable oil as a raw material; then carrying out the D-A addition reaction on the vegetable oleate and maleic anhydride or a derivative thereof under the condition of UV light irradiation and a catalyst; and finally preparing the UV photocatalysis-based unsaturated vegetable oil D-A reaction product. A UV photochemical reaction process and a UV photochemical reaction mechanism of the unsaturated vegetable oil series are researched, the preparation of an ideal target product is further regulated and controlled, thus the research thought is creative. The UV photocatalysis-initiated unsaturated vegetable oil D-A addition reaction is researched and is applied to prepare a vegetable oil derivative so as to optimize the UV reaction activity and the solidification property.

A homogeneous solid metallocene catalyst carried by polystyrene for the polymerization of olefin is prepared through introducing the cyclopentadienyl to linear polystyrene chain and loading the metallocene into the cross-linked polystyrene network by the Diels-Alder cross-linking reaction under existance of metallocene. It features that when it is used for the polymerization of olefin, the cross-linked network of carrier can be gradually opened, resulting in smooth dynamic performance.

The present invention achieves increased filler interaction by incorporating a small amount (a few units per chain of rubbery polymer) of a conjugated triene monomer, such as alloocimene, randomly throughout the polymer chain of a rubbery polymer or at the chain ends of the rubbery polymer. The incorporation of the conjugated triene monomer leads to the formation of a polymer containing highly reactive conjugated diene units. These conjugated diene units can chemically react with carbon black leading to superior reinforcement. Alternatively, these conjugated diene units can be used for functionalization of the polymer with silica interactive/reactive groups using Diels Alder reactions. This functionalization of the rubbery polymer can conveniently be conducted in a mixer, such as a Banbury mixer, a mill mixer, or the like. The present invention more specifically discloses a rubbery polymer having repeat units which are comprised of (1) an olefin monomer selected from the group consisting of conjugated diolefin monomers and monoolefin monomers and (2) a conjugated triene monomer. The subject invention further reveals a rubbery composition which is comprised of the reaction product of (I) a rubbery polymer having repeat units which are comprised of (1) an olefin monomer selected from the group consisting of conjugated diolefin monomers and monoolefin monomers and (2) a conjugated triene monomer and (II) a dienophile and/or dienophile which is functionalized with a group which is capable of reacting with a filler selected from the group consisting of carbon black, silica, starch, and cellulose.

A reversible viscosity reducing polymer is provided that has a crosslinkage between subunits inclusive of a single Diels-Alder Such a reversible viscosity reducing polymer is particularly well suited as a matrix material for a heterogeneous propellant. A process for forming a reversible viscosity reducing polymer inclusive of a single Diels-Alder linkage includes reacting a native crosslinkable moiety with a crosslinker moiety having a Diels-Alder reactive moiety of a diene or dienophile to form a Diels-Alder reactive moiety capped polymer subunit. The Diels-Alder reactive moiety capped polymer subunit is then exposed to a Diels-Alder reactant inclusive of a complementary Diels-Alder reactive moiety where the reactant also includes at least one conventional crosslinkable moiety to form a crosslinkable moiety capped polymer subunit. Reaction of the crosslinkable moiety capped polymer subunit is then reacted with a conventional multifunctional crosslinking agent.

The invention relates to a method for preparing ambrotone. The method includes steps of 1, synthesizing 3-methyl-3-pentene-2-ketone; 2, carrying out diene addition for preparing ambrotone intermediates; 3, carrying out cyclization reaction to prepare the ambrotone. Diene addition for preparing the ambrotone intermediates is carried out without catalysts by the aid of high-temperature gas-phase reaction. The method has the advantages that the ambrotone is prepared from raw materials beta-pinene, butanone and acetaldehyde, other organic solvents are omitted, high-pollution and high-carcinogenesis substances such as benzene and toluene are omitted, accordingly, the cost can be lowered, the quality of products can be effectively improved, the application range of the products can be effectively expanded, and Diels-Alder condensation reaction is carried out by the aid of the high-temperature gas-phase reaction; the Diels-Alder condensation reaction is carried out by the aid of the high-temperature gas-phase reaction or atomized small-molecule water drop and gas phases, catalysts such as Lewis acid or proton acid are omitted at reaction steps, accordingly, the production cost can be lowered, technological equipment can be simplified, post-reaction treatment working procedures can be shortened, and the purpose of zero sewage discharge can be truly achieved.

A composition is provided that includes a polymer matrix. A core having a core surface is embedded within the polymer matrix. A polymeric ligand passivates the core surface and has a moiety Y, where Y is a Diels-Alder group of a diene or dienophile. A polymeric linker has a complementary Diels-Alder group diene or dienophile to moiety Y and forms a Diels-Alder bond with the moiety Y. A composition is also provided that includes polymer matrix having a matrix surface. A core having a core surface is present on the matrix surface. A polymeric ligand passivates the core surface and has a moiety Y, where Y is Diels-Alder group of a diene or dienophile. The polymer matrix and polymeric ligand together define a matrix-ligand Flory-Huggins binary interaction function greater than 0.