107 results about "Meta-phenylenediamine" patented technology

The invention discloses a preparation method of high-strength high-modulus PMIA super-short fiber, comprising: m-phthaloyl chloride and metaphenylene diamine are adopted in a system of which the sulphonamide compound is an organic solvent to polymerize solution to obtain m-phenyleneisophthalamide (PMIA) solution comprising polymetaphenylene isophthamide as a repeating unit; performing neutralization reaction by calcium oxide or calcium hydroxide to generate hydrochloric acid so as to obtain spinning solution, wherein the logarithmic viscosity number of the spinning solution is 3-6; high-strength high-modulus PMIA super-short fiber of which the length is 0.5-20 mm is prepared by wet spinning, cleaning, heat treatment, winding, cutting off and packaging. The strength and the modulus of the PMIA super-short fiber are greatly improved compared with the existing like products.

The preparation process of aromatic mata-polyamide with raised fire resistance includes mixing m-phenylene-diamine and R, R'-dismino diphenylsulfone and dissolveing in solvent to compound solution in certain concentration, cooling to -10 deg.c to 0 deg.c, adding m-phenyldimethyl acyl chloride to produce condensation while controlling the reaction temperature in 0-40 deg.c until the solution reaches the target apparent viscosity to obtain aromatic mata-polyamide with raised fire resistance. The present invention has raised production efficiency, lowered production cost, raised vitrification point and raised strength and module of subsequent product.

The invention relates to a surface modification method for a lossless environment-friendly convenient aramid fiber material. The surface modification method comprises the following steps of: taking and placing a Tris-HCl buffer solution with the Ph of 0.7-10.8 in a flask, adding the aramid fiber material into the buffer solution for fully steeping, adding a dopamine hydrochloride modifying agent to the flask, reacting in an open environment under the magnetic stirring condition, and enabling the self-polymerization of the modifying agent to occur; washing and drying the reacted aramid fiber material to obtain the aramid fiber material with modified surface; and continuously steeping the modified aramid fiber material in the dopamine hydrochloride modifying agent solution to enable the self-polymerization of the aramid fiber material to occur, thereby obtaining the modified aramid fiber material with the activated surface and adjustable thickness. The aramid fiber material is a poly-p-phenylene terephthamide or polyisophthaloyl metaphenylene diamine long fiber, chopped fiber or powder. The concentration of the dopamine hydrochloride in the buffer solution is 0.05-2.0mg/ml. A poly-dopamine layer rich in catechol groups is formed on the surface of the modified aramid fiber material obtained by the method; and the modified aramid fiber material has excellent reaction activity and is adjustable in thickness.

The invention relates to a cross-linked sulfonated polysulfone/polyether sulfone-sulfonated polysulfone composite membrane and a manufacturing method of the cross-linked sulfonated polysulfone/polyether sulfone-sulfonated polysulfone composite membrane. Polyhydroxyl or multi-amino or hyperbranched substances are selected, a polyether sulfone/sulfonated polysulfone blended ultra-filtration base membrane is coated with a cross-linked sulfonated polysulfone solution to manufacture the composite membrane, a composite membrane separation layer of which the thickness is 1 micrometer-10 micrometers is formed on the surface of the base membrane, the water contact angle of the surface of the composite membrane separation layer ranges from 40 degrees to 90 degrees, and the composite membrane separation layer has good osmosis and separation properties. The manufacturing method includes the steps that sulfonated polysulfone of different concentrations and sulfonation degrees, m-phenylenediamine, polyethylene glycol, dopamine, H30 and other cross-linking agents are dissolved in solvent to manufacture the coating solution, with the polyether sulfone/sulfonated polysulfone blended ultra-filtration being the base membrane, the composite membrane separation layer is manufactured under vacuum conditions, and finally the cross-linked sulfonated polysulfone/polyether sulfone-sulfonated polysulfone composite membrane which is hydrophilic is obtained. The manufactured composite membrane has the good osmosis and separation properties, and can be used for nanofiltration and forward osmosis processes and membrane separation processes including seawater desalting, waste water treatment, domestic water treatment and bio-separation.

A preparation method of high-thermal-conductivity aromatic polyamide fibers includes dispersing oxidized graphene in an organic solvent to obtain dispersion liquid; adding m-phenylenediamine monomers into the dispersion liquid under the protection of inert gas, and cooling a system to a temperature as required by the system; slowly adding part of isophthaloyl dichloride while stirring to allow a polycondensation reaction of the solvent, adding alkaline substances for neutralization, adding the rest isophthaloyl dichloride, and continuing to stir until complete reaction to obtain a meta-position aromatic polyamide resin solution; taking the meta-position aromatic polyamide resin solution as a spinning solution, adopting a dry-spraying and wet-spinning process to spin, and finally preparing the high-thermal-conductivity aromatic polyamide fibers. The high-thermal-conductivity aromatic polyamide fibers have high thermal diffusion coefficients; added carbon nano-materials, graphite nano-materials and the like have antifriction effect, and serve as structure reinforcing materials which obviously improve mechanical properties of aramid fibers.

The inventioin discloses a polyisophthaloyl metaphenylene diamine fiber with the strength of 5.2-10.8 cN/dtex and the elongation at break of 2.0-5.0. The invention simultaneously discloses a preparation method of the polyisophthaloyl metaphenylene diamine fiber. The preparation method comprises steps as follows: firstly, metaphenylene diamine and isophthaloyl dichloride are subjected to polymerization reaction, and then, spinning operation is performed. According to the preparation method, gaseous hydrogen chloride produced in the dry spray stage and ammonia gas in a gas storage box react, the amount of hydrogen chloride discharged to the environment is reduced, ammonia gas and dry spray trickle are fully contacted, and forming of a macroscopic void structure during fiber solidification can be inhibited; the polyisophthaloyl metaphenylene diamine fiber prepared and obtained with the method has the advantages of compact structure, high strength and toughness, large specific surface area and convenience for fiber dyeing; and by means of the preparation method, the production efficiency of aramid fiber is improved greatly, and industrial mass production requirements of aramid fiber are met.

The invention provides a preparation method for a polyisophthaloyl metaphenylene diamine nanofiltration membrane and belongs to the field of membrane pollution resistance. The method includes the steps that a fully-dried polyisophthaloyl metaphenylene diamine nanofiltration membrane is flatly laid on a glass plate, the glass plate is placed in a plate frame to be tightened, a prepared solution containing an acid binding agent is poured to the surface of the membrane for impregnation, the remaining solution is poured out, and the membrane is placed in a fume cupboard to be dried in shade; then a prepared crosslinking solution is poured to the surface of the membrane for impregnation, and the surplus solution is removed through a silica gel wheel; then an oxidized graphene solution is poured to the surface of the membrane for impregnation, the remaining solution is poured out, and the membrane is dried in shade; finally the treated membrane is placed within the temperature interval of 40-80 DEG C for heat treatment for 60-180 s, and the modified nanofiltration membrane is obtained. The technological operation is easy, the original excellent characteristics of the polyisophthaloyl metaphenylene diamine nanofiltration membrane are kept, the hydrophilia of the surface of the membrane is also well enhanced, the pollution resistance of the membrane is improved, and wide application prospects are achieved.

The invention discloses a method for preparing high-throughput and anti-pollution polyisophthaloyl metaphenylene diamine nano-filtration membranes, and belongs to the field of technologies for preparing membranes. The method includes sulfonating polyether ether ketone concentrated sulfuric acid, cleaning the polyether ether ketone concentrated sulfuric acid until the polyether ether ketone concentrated sulfuric acid is neutral and drying the polyether ether ketone concentrated sulfuric acid to obtain sulfonated polyether ether ketone; adding 0.01-1 wt% of treated graphene oxide and 0.01-10 wt% of sulfonated polyether ether ketone into N, N-dimethylacetamide (DMAC) to obtain mixtures, placing the mixtures in a cell grinder and treating the mixtures to obtain dispersion liquid; adding additives into the dispersion liquid with the graphene oxide and the sulfonated polyether ether ketone, stirring the additives and the dispersion liquid to obtain first mixtures, then adding dried PMIA [poly(m-phenylene isophthalamide)] into the first mixtures, dissolving the dried PMIA and the first mixtures at the temperature of 80 DEG C to obtain second mixtures, mechanically stirring the second mixtures, carrying out vacuum defoaming on the second mixtures, preserving the second mixtures for standby application and forming the high-throughput and anti-pollution polyisophthaloyl metaphenylene diamine nano-filtration membranes by means of scraping. The method has the advantages that the method is easy to implement, contact angles of the high-throughput and anti-pollution polyisophthaloyl metaphenylene diamine nano-filtration membranes prepared by the aid of the method can be reduced and reach approximately 45 degrees from the original approximately 78 degrees under the condition that the retention rates keep rising, and the hydrophilicity and the anti-pollution performance of the high-throughput and anti-pollution polyisophthaloyl metaphenylene diamine nano-filtration membranes can be greatly improved.

A composite reverse osmosis polyester-amide membrane is composed of a porous supporting layer, and a compact polyester-amide surface layer prepared by interface polymerization between aminoglucose or aminobiglucose or the mixture of aminoglucose and metaphenyldiamine and the polyatomic acyl chloride. Its preparing process includes such steps as immersing the one surface of polysulfone film in the aqueous solution of amino monomer, dripdrying, interface polymerization reaction on the solution of polyatomic acyl chloride, drying, heat treating and rinsing in deionized water. It has high water throughput.

The present invention relates to a novel nickel catalyst. The present invention also relates to a process for the preparation of an improved nickel catalyst. The present invention also relates to a process for hydrogenation of m-dinitro benzene to m-phenylene diamine using the said improved catalyst. More particularly the present invention relates to a process involving hydrogenation of m-dinitrobenzene to m phenylene diamine in the presence of a supported bimetallic platinum catalyst, using methanol as a solvent. The catalyst system consisting of one metal selected from platinum group and other nickel supported on either carbon or alumina or silica or zeolite. The catalyst of the present invention is a bimetallic catalyst prepared by precipitation and impregnation technique at very specific preparation conditions.

A base paper of aramid fiber honeycomb core and its manufacturing method are provided. The base paper comprises 11-90 parts by weight of structural fiber, 10-70 parts by weight of crosslinking fiber, and 0-19 parts by weight of additive fiber, wherein the structural fiber is poly(p-phenylene terephthal amide) fiber, the crosslinking fiber is poly(m-phenylene isophthal amide) fibrid, and the additive is polyester fiber.

The invention discloses a method for improving the water flux and anti-pollution ability of a polyamide reverse osmosis membrane, specifically: dissolving polysulfone in N-N, dimethylacetamide solution, adding sodium dodecylsulfonate, Mix well, apply and scrape on the surface of non-woven fabric, immerse in water, remove the solvent to obtain a polysulfone support layer, and then treat the polysulfone support layer with ultraviolet light; rinse the surface of the polysulfone support layer with deionized water repeatedly, and after air-drying, Immerse it in an aqueous solution of m-phenylenediamine, form an aqueous liquid layer on the surface of the polysulfone support layer, and prepare a wet film; immerse the wet film in a naphtha organic solution of trimellitic acid chloride, and interfacially polymerize with it Reaction; immersing the polyamide composite reverse osmosis membrane in an aqueous solution of sodium sulfate; then immersing it in an aqueous solution containing hydroxyethyl acrylate, and performing a contact reaction to obtain a high-flux anti-pollution polyamide composite reverse osmosis membrane. The invention has strong anti-pollution ability, and the water flux is improved compared with the traditional reverse osmosis membrane under the same pressure.

A polymetaphenylene isophthalamide porous hollow fiber membrane is produced by extruding a film-forming solution comprising polymetaphenylene isophthalamide, polyvinylpyrrolidone and an inorganic salt through a concentric double annular spinning nozzle while keeping the film-forming solution at 70° C. or higher, thereby conducting dry-and-wet spinning, followed by moisture retention treatment, where it is preferable to subject the resulting porous hollow fiber membrane obtained by dry-and-wet spinning to heat treatment in water at 80° C. or higher before the moisture retention treatment. The polymetaphenylene isophthalamide porous hollow fiber membrane resulting from wet heat treatment under wet heat conditions at the temperature of 100° C. and the humidity of 80% for 1,000 hours or more has a strength at break of 10 MPa or more and a elongation at break of 80% or more, where the elongation at break can keep at least 80% as high as that before the wet heat treatment, and also has distinguished resistance to moisture and heat and humidifying performance, so that the membrane can be used as an effective humidifying membrane for polymer electrolyte fuel cells, etc.

The invention relates to a fissility shrinkable film, containing 60-85 mass portion of nylon 6 (Ny6) and 15-40 mass portion of m(p-xylylene adipamide) (MXD6) (total is 100 mass portion) as materials. The material comprises original materials containing 60-85 mass portion of Ny and 15-40 mass portion portion of MXD, and a heat processing matter for melting refining the Ny6 and MXD6 to make the MXD6 melting point be 233-238 DEG C. The content of the heat processing matter is 5-40 mass%. The shrinkage of the fissility shrinkable film is 3-20% when keeping in the hot water at 95 DEG C for 30 mins.

The invention relates to a method for improving polyisophthaloyl metaphenylene diamine hollow fiber nanofiltration membrane hydrophilism and pollution resistant performance. Polyisophthaloyl metaphenylene diamine is used as raw materials, after fully mixing and dissolving with organic dissolvant and pore-foaming agent, nanometer titania particles are increased, fully blended and uniformly distributed, after standing vacuum defoaming, and the hollow fiber nanofiltration membrane is manufactured by adopting an immersion sediment phase inversion method in a pulling mode. The content of the polyisophthaloyl metaphenylene diamine in membrane-manufacturing original liquid is 10%-25wt.%, the content of the organic dissolvant is 50%-70wt.%, the content of the pore-foaming agent is 5%- 25wt.%, and the content of nanometer titania particles is 0.5%- 4wt.%. The prepared hollow fiber nanofiltration membrane contact angle is lowered from 70 degrees to 40 degrees, in the meantime possesses good mechanical property. Tensile strength can meet 10.0 Mpa-18.0 Mpa, and an elongation at break is in the range of 80%-150%. The method for improving polyisophthaloyl metaphenylene diamine hollow fiber nanofiltration membrane hydrophilism and pollution resistant performance has the advantages of being simple in operation, capable of reserving the original good features of the polyisophthaloyl metaphenylene diamine hollow fiber nanofiltration membrane, and further enhancing the hydrophilism of surfaces of membranes, improving the anti-pollution performance of the membranes and wide in application prospect.

The invention relates to a preparation method of a nitrogen-doped carbon/graphene/manganese oxide composite material and an application of the nitrogen-doped carbon/graphene/manganese oxide composite material in electrocatalytic reduction of oxygen. The method comprises the following steps of preparing the nitrogen-doped carbon/graphene/manganese oxide composite material; and modifying the nitrogen-doped carbon/graphene/manganese oxide composite material on an electrode to test the electrocatalytic activity of the material on oxygen reduction. The preparation method has the beneficial effects that the nitrogen-doped carbon/graphene/manganese oxide composite material is prepared by a simple and feasible method; in the overall preparation process, poly-metaphenylene diamine plays an important role; graphene reserves a large specific surface area, and poly-metaphenylene diamine is a nitrogen source of nitrogen-doped carbon; and finally the nitrogen-doped carbon/graphene/manganese oxide composite material has excellent oxygen reduction electrocatalytic properties.

The invention discloses a synthetic method of polymetaphenylene diamine nanoparticles, and the method is divided into two stages of prepolymerization and oxidation polymerization. The method comprises the following steps: firstly adding a divalent copper ion solution into an aqueous solution of metaphenylene diamine, stirring and reacting for 10-30 min to perform a prepolymerization reaction; then, gradually adding a persulfate aqueous solution and alkali liquor simultaneously within 30-60 min, initiating oxidation polymerization, and continuing stirring and reacting for 5-8 hours; filtering, and washing to obtain the polymetaphenylene diamine nanoparticles. The conversion rate of metaphenylene diamine monomer is up to 90%-98%, and the generation amounts of metaphenylene diamine monomer and its oligomer are effectively reduced. The method of the invention can prepare nanoscale polymetaphenylene diamine with high efficiency, is economical, effective, and simple in operation, and has a greatly improved monomer conversion rate.

The invention discloses a modified meta-aramid polymer and a preparation method thereof. Metaphenylene diamine, alkyl diamine H2N-M-NH2 and various diamine monomers such as halogenated diamine monomers are poly-condensed with isophthalic chloride by a low-temperature solution polycondensation method to form the modified meta-aramid polymer, wherein the isophthalic chloride is repeatedly added intoreaction solution. The invention further discloses a preparation method for preparing a hollow fiber membrane by the prepared meta-aramid polymer. The prepared modified meta-aramid polymer keeps original excellent performances, further has low intrinsic viscosity and good chlorine resistance and is more applicable to spinning of the hollow fiber membrane, the prepared membrane is more easily preserved in a dry state, and the preparation method is simple, easy to operate and suitable for industrial production and has an excellent market application prospect.

The invention relates to a method for preparing meta-position aramid fibers. The method is characterized by comprising the following steps: specially preparing a spinning solution of three components such as poly(m-phenyleneisophthalamide), hydrogen chloride and N, N-dimethylacetamide through adopting polymerization; deaerating the solution, then heating the solution, extruding the solution through a spinneret plate to enter a spinning hot channel, and removing solvents such as the N, N-dimethylacetamide and the hydrogen chloride through the hot channel so as to obtain nascent fibers; and stretching the nascent fibers through the solvent, washing to further removing the hydrogen chloride and the solvent in the nascent fibers, then drying, dry heating and stretching, cooling and oiling to obtain the finished fibers. The poly(m-phenyleneisophthalamide) spinning solution does not contain salt, and the deionized water and the solvent instead of salt are used in a whole fiber production process, so that the finally prepared meta-position aramid fiber products are low in ion content and fiber ash content; and solvent recovery steps are simplified, and energy sources are greatly saved.