16 results about "Dimethyl acetamide" patented technology

The invention relates to a synthesis method of an allyl amine compound. According to the method, 2-methylquinoline or acetophenone derivatives are used as raw materials, a selective fluorine reagent Selectfluor is used as an accelerant, dimethyl sulfoxide and N 'N-dimethylacetamide are used as a mixed solvent, and the allyl amine series compounds are prepared with high yield. The preparation method has the advantages of being low in cost, easy to operate, green, free of pollution and the like, and has potential industrial application prospects. The method provides a green, cheap and convenient way for preparing the allyl amine derivative by using 2-methylquinoline or acetophenone compounds as initiators.

This invention discloses an organosilicon side-chain modified acrylate polymer antifouling coating and its preparation method. The antifouling coating consists of component A and component B. Component A is prepared by dissolving polytetrahydrofuran ether diol in N,N-dimethylacetamide and reacting it with diisocyanate. Component B is prepared by mixing methyl methacrylate, acrylic acid, hydroxyacrylate, acryloyloxypropylsilane, and ethyl acetate, adding a peroxide initiator, and then performing free radical polymerization. The antifouling coating prepared by this invention exhibits excellent substrate adhesion and antifouling properties, making it suitable for antifouling of marine vessels.

The application provides a method for catalytic degradation of polyolefin plastic by using a eutectic solvent, comprising the following steps: placing polyolefin plastic particles, C4-C6 alkane, amide-AlCl3 eutectic solvent, initiator and polychloromethane in a reactor to perform a catalytic degradation reaction in a water-free and sealed environment to obtain a hydrocarbon product; wherein the C4-C6 alkane is added before the polyolefin plastic particles and the amide-AlCl3 eutectic solvent coexist in the reactor; the amide-AlCl3 eutectic solvent comprises an amide compound and AlCl3; the amide compound is selected from one or more of chloroacetamide, formamide, acetamide, N-methyl formamide, N-methyl acetamide, N,N-dimethyl acetamide, N,N-diethyl acetamide and N,N-dimethyl formamide; the application first applies the eutectic solvent to the catalytic degradation of the polyolefin plastic, and solves the problems of low efficiency and high cost of the traditional method at low temperature.

A process for producing cellulose ester fibers is provided, the process comprising dry spinning a cellulose ester dope through a spinneret to make the cellulose ester fibers, wherein the cellulose ester dope comprises dissolved and / or dispersed solids (hereinafter "solids" ) and solvent, at least 35 wt. % of the solids comprises cellulose ester, and the solvent comprises N, N-dimethylformamide, N,N-dimethylacetamide, or dimethyl sulfoxide, or mixtures thereof, provided that if the solvent comprises N, N-dimethylacetamide: (i) the cellulose ester dope comprises not more than 50% by weight acetone, based on the total weight of the cellulose ester dope; or (ii) the cellulose ester dope comprises 0% by weight cellulose nanocrystals based on the total weight of the cellulose ester dope; or (iii) both (i) and (ii), wherein the combined weight of a polyurethane, polyolefin, nylon, polyester, and / or polyurethaneurea, if present in the cellulose ester dope, is not more than 60% by weight, based on the total solids in the cellulose ester dope; and wherein there is a substantial absence of an organic acid.

Provided are silica sols containing organic acids dispersed in nitrogen-containing organic solvents, and insulating resin compositions comprising the silica sol and nitrogen-containing polymers. The silica sol is a silica sol in which silica particles having an average primary particle size of 5-100 nm are dispersed in a nitrogen-containing organic solvent, and the silica sol contains a carboxylic acid with 1-3 carbon atoms in a proportion of 80-1500 ppm. The nitrogen-containing organic solvent is an amide-based silica sol. The nitrogen-containing organic solvent is a silica sol containing dimethylacetamide, dimethylformamide, or dimethylpropionamide. The carboxylic acid with 1-3 carbon atoms is a silica sol containing formic acid, acetic acid, or propionic acid. The insulating resin composition comprises a silica sol and a nitrogen-containing polymer.

The application belongs to the technical field of preparation of flame-retardant fibers, and discloses a preparation method of flame-retardant polyacrylonitrile fibers and the flame-retardant polyacrylonitrile fibers, the preparation method comprising the following steps: (1) adding a composite flame retardant powder and a polyacrylonitrile powder into dimethylacetamide, grinding and dispersing, and then filtering to obtain a flame-retardant slurry; (2) adding the polyacrylonitrile powder into dimethylacetamide, uniformly mixing, and heating to completely dissolve to obtain a polyacrylonitrile stock solution; (3) preparing a spinning stock solution: uniformly mixing the flame-retardant slurry and the polyacrylonitrile stock solution according to the mass ratio of the composite flame retardant to the polyacrylonitrile being 1:2.3-4.0 to obtain the spinning stock solution; and (4) spinning by using the spinning stock solution to prepare the flame-retardant polyacrylonitrile fibers. The application adds a certain amount of polyacrylonitrile in the flame-retardant slurry, which can more easily uniformly mix with the polyacrylonitrile stock solution, can increase the addition amount of the composite flame retardant in the fibers, and will not obviously affect the mechanical properties of the fibers.

The invention relates to a continuous preparation method of 2-chloro-N, N-dimethyl nicotinamide, and belongs to the technical field of organic synthesis. In a tubular reactor, 3-di-n-propylamino acrolein and 2-cyano-N, N-dimethylacetamide are used as raw materials to react, the obtained product reacts with hydrogen chloride, and 2-chloro-N, N-dimethyl nicotinamide is obtained. The tubular reactor is adopted for continuous production, so that the reaction period is greatly shortened, the process operation is reduced, and the reaction cost is reduced.

This invention discloses a fiber pretreatment method and the application of the pretreated fibers. The method involves dissolving the fibers in dimethylacetamide at room temperature to obtain dissolved fibers. These dissolved fibers are then treated in a LiCl / DMAc solution. After removing the reagents by squeezing, the fibers are washed, filtered, and dried to obtain pretreated fibers. These pretreated fibers are then used in the preparation of glue-free laminated fiberboard. The LiCl / DMAc solution treatment significantly increases the area of ​​the self-bonding interface of the fibers and enhances the surface hydroxyl activity. During the glue-free bonding process, not only do the degradation products of hemicellulose and lignin self-bond, but cellulose also melts and regenerates to form filaments, which then self-bond under hydrogen bonding, significantly improving the performance of the glue-free laminated board.

Provided are stable, concentrated, and palatable solutions suitable for sublingual and / or transurethral administration containing tadalafil, with or without other active ingredients to address comorbidities, in a liquid vehicle or solvent selected from propylene carbonate, 2-pyrrolidone, dimethyl isosorbide, dimethyl acetamide, n-methyl-2-pyrrolidone, ethanol, water, oleic acid, and isopropyl myristate. The solutions have low irritancy for sublingual tissues and a-are compatible with commercial atomizers. The invention is further directed to methods of treating male erectile dysfunction and / or comorbidities by administering an effective amount of the pharmaceutical formulations comprising tadalafil, with or without other active ingredients, to a patient in need of such treatments.

A process for producing cellulose ester fibers is provided, the process comprises dry spinning a cellulose ester dope through a spinneret to make the cellulose ester fibers, wherein the cellulose ester dope comprises dissolved and / or dispersed solids (hereinafter "solids") and solvent, at least 35 wt.% of the solids comprises cellulose ester, and the solvent comprises N, N-dimethylformamide, N, N-dimethylacetamide, or dimethyl sulfoxide, or mixtures thereof, provided that if the solvent comprises N, N-dimethylacetamide: (i) the cellulose ester dope comprises not more than 50% by weight acetone, based on the total weight of the cellulose ester dope; or (ii) the cellulose ester dope comprises 0% by weight cellulose nanocrystals based on the total weight of the cellulose ester dope; or (iii) both (i) and (ii), wherein the combined weight of a polyurethane, polyolefin, nylon, polyester, and / or polyurethaneurea, if present in the cellulose ester dope, is not more than 60% by weight, based on the total solids in the cellulose ester dope; and wherein there is a substantial absence of an organic acid.

A highly efficient carbon fiber surface treatment method and its composite material belong to the field of composite material technology. Step 1: Wash the carbon fiber with acetone to completely remove sizing agent and impurities, then dry it. Step 2: Wind the carbon fiber onto a glass frame and perform plasma treatment under an O2-Ar mixed gas atmosphere. Step 3: Dissolve polyimide resin in N,N-dimethylacetamide to prepare a resin solution. Step 4: Prepare a prepreg by combining the carbon fiber and resin solution. Step 5: Stack multiple prepreg sheets, set a stepped heating program, and prepare the composite material by high-temperature hot pressing. In this invention, Ar plasma etches the carbon fiber surface, increasing the surface area and surface roughness, while O2 plasma introduces oxygen-containing functional groups into the carbon fiber surface. The synergistic effect of these two processes improves the mechanical interlocking and chemical bonding between the carbon fiber and the resin matrix, significantly enhancing the interlaminar shear strength at both room temperature and high temperature.

The application discloses an antibacterial fiber and a preparation method and fabric thereof, relates to the technical field of functional fibers, and belongs to the patent publication D01F6 / 54. The preparation method of the antibacterial fiber comprises the following steps: uniformly mixing acrylonitrile monomers, vinyl acetate, methyl methacryloyloxyethyl trimethyl ammonium chloride and anhydrous ethanol to obtain a mixed solution; adding polyvinyl alcohol into the mixed solution and performing heating and stirring reaction to obtain polyacrylonitrile copolymer powder; adding polyvinylpyrrolidone and nano zinc oxide into dimethylacetamide to obtain nano antibacterial dispersion slurry; adding the polyacrylonitrile copolymer powder into the nano antibacterial dispersion slurry to obtain composite nano antibacterial spinning stock solution; and conveying the composite nano antibacterial spinning stock solution to a spinning machine for spinning to obtain the antibacterial fiber. The antibacterial fiber fabric prepared by the application has excellent antibacterial performance and antibacterial durability.

The application discloses a kind of superfine high-strength meta-aramid fiber and its preparation method, by adjusting wet spinning coagulation bath type and reducing coagulation bath temperature, realize super-drawing, to obtain superfine high-strength meta-aramid fiber.Ethyl acetate and dimethylacetamide are used as coagulation bath, and the temperature of coagulation bath is reduced at the same time, so that the coagulation speed of the fiber in the coagulation bath is slower, and the intermolecular force of the fiber is stronger, forming a more stable network gel state, with very excellent stretchability.The meta-aramid fiber prepared by the method has a diameter of 1.43um, a tensile ratio of up to 8000 times, a breaking strength of 1332MPa, and an elongation at break of more than 20%.

The invention relates to the field of crude product separation in the production process of epoxy chloropropane, and discloses a method for separating chloropropene-chloropropane. The method comprises the following steps: (1) in the presence of an extraction agent, carrying out extractive distillation on a crude product containing chloropropane and chloropropene to obtain a chloropropane product and a mixture of chloropropene and the extraction agent; (2) separating the chloropropene and extractant mixture to obtain a chloropropene product and an extractant; the extraction agent is selected from at least one of water, furfural, aniline, ethylene glycol, 1, 3-propylene glycol, glycerol, dimethyl sulfoxide, N-methyl pyrrolidone, N, N-dimethyl formamide and N, N-dimethyl acetamide. The method provided by the invention realizes effective separation of chloropropene and chloropropane, and the chloropropene product obtained by separation has high purity and low energy consumption.

The invention discloses a preparation method of flame-retardant heat-insulating carbon fibers with a three-dimensional cage carbon structure, and belongs to the technical field of composite flame-retardant materials. The preparation method comprises the following steps: mixing and dispersing epoxy resin, polyhedral oligomeric silsesquioxane and dimethylacetamide to form a mixed solution, mixing the mixed solution, a curing agent, an accelerant and a coupling modifier to form a mixed spinning solution, and performing electrostatic spinning on the mixed spinning solution to obtain a nanofiber felt; polyacrylonitrile precursors are sequentially subjected to pre-oxidation treatment and carbonization treatment to obtain carbon fibers, the carbon fibers are subjected to anodic oxidation treatment to obtain pretreated carbon fibers, and the pretreated carbon fibers are dip-coated with a sizing agent to obtain modified carbon fibers; the modified carbon fiber and the nanofiber felt are bonded through a flame-retardant fire-extinguishing adhesive, and are subjected to hot press molding to obtain the flame-retardant heat-insulating carbon fiber. The flame-retardant and heat-insulating carbon fiber prepared by the invention not only has good flame-retardant and heat-insulating properties, but also has good mechanical properties.

The application discloses a high-ionic-conductivity high-temperature-resistant lithium ion battery diaphragm and a preparation method thereof, and belongs to the technical field of battery diaphragms, and is used for solving the technical problem that the high-temperature resistance and ionic conductivity of the lithium ion battery diaphragm in the prior art need to be further improved. The preparation method of the high-ionic-conductivity high-temperature-resistant lithium ion battery diaphragm comprises the following steps: dissolving polyphthalic amide and modified cellulose into an N,N-dimethylacetamide solution to form a spinning solution, and then adopting electrostatic spinning to prepare a spinning base film with a thickness of 29-31 mu m. After the electrostatic spinning of the polyphthalic amide and the modified cellulose as raw materials, the triazine modification is performed on the spinning base film, and then the inorganic coating liquid is used for coating, so that the mechanical strength and the heat-resistant stability of the battery diaphragm are effectively improved, the ionic conductivity is also improved, and the charging and discharging efficiency of the lithium battery is improved.