45results about How to "Shorten the synthesis process" patented technology

The invention discloses a continuous preparation method for semi-aromatic polyamide. The method is characterized by comprising the following steps that: 1 to 50 parts by weight of a catalyst per hour and 1000 to 5000 parts by weight of a semi-aromatic polyamide prepolymer per hour are mixed and then added into a reaction extruder through a main feeding inlet of the extruder; 1 to 10 parts by weight of a molecular weight regulator per hour and 100 to 500 parts by weight of a dispersing material per hour are mixed and then added through an auxiliary feeding inlet; then reactive extrusion is carried out under the conditions of a temperature of 280 to 330 DEG C, a screw rotation speed of 10 to 200 rpm and a vacuum degree of 0.04 to 0.09 MPa; and traction, cooling, granulation and drying are carried out on obtained extrudate so as to obtain semi-aromatic polyamide resin.

The invention discloses a macromolecule-metallic oxide compound. The macromolecule-metallic oxide compound comprises a metallic oxide particle located in the center and a macromolecule modified on thesurface of the metallic oxide particle, the macromolecule has a functional group capable of being bonded with a metal in the metallic oxide, and the density of a binding site of the polymer and the surface of the metallic oxide is more than 2 binding sites per square nanometer. The invention further discloses a preparation method of the macromolecule-metallic oxide compound and application of themacromolecule-metallic oxide compound as a nuclear magnetic resonance contrast medium and an iron supplement agent. The disclosed macromolecule-metallic oxide compound greatly prolongs the circulation time of the macromolecule-metallic oxide compound in a body and effectively overcomes the defect that the existing contrast medium causes the hypersensitivity, and as the compound has superparamagnetism and has the function of participating in iron metabolism, the macromolecule-metallic oxide compound can be applied as the nuclear magnetic resonance contrast medium and the iron supplement agentused for treating iron-deficiency anaemia.

The invention discloses a pyrocatechol derivative and a preparation method of the derivative. The preparation method of the derivative comprises the following steps of: (1) taking an aryl phenol compound as a substrate, and 2-chlorine-5-nitryl pyrimidine as an orienting group, slowly adding a redistilled tetrahydrofuran solvent ice bath into sodium hydride in the presence of nitrogen for reactionto form a pyrimidine aryl phenol compound intermediate, (2) taking iodobenzene diacetate as an oxidant and palladium acetate as a catalyst, catalyzing the pyrimidine aryl phenol compound intermediatefor C-H activating reaction in a solvent, performing swab-off, and chromatographic separation and purification to form an acetoxylated phenylamine derivative, and (3) allowing the acetoxylated phenylamine derivative to react in a tetrahydrofuran solvent by using hydrazine hydrate, and performing quenching, washing, extraction, drying, swab-off, and chromatographic separation and purification to form an ortho-aminophenol derivative. The first two steps of the method can be achieved in a pot, and small-scale production of above a 'gram' level can be even achieved.

The present invention discloses a preparation method for an anatase type bentonite-based porous TiO2 nanometer material. The preparation method is that the organic bentonite after dehydration and drying or the organic bentonite abandoned after wastewater treatment is added with the mixture of amine and titanate or only added with titanate; then after well mixing and centrifuging, the supernate isabandoned and the solid part left will be removed from surfactant and organic materials through drying and high-temperature calcinations, thus the porous TiO2 nanometer material is obtained. The material prepared by the invention is of large specific surface area, smaller grain size, single particle size and uniform pore distribution, wherein, the aperture ranges between micropore and mesopore andthe pores are in high sequence degree. The material is mainly anatase type and is provided with relatively high catalytic activity, which can be applied to the indoor organic pollutant purification field. At the same time, the present invention provides a very good solution to the ultimate disposition of abandoned organobentonite, and makes good use of the abandoned organobentonite after wastewater treatment to achieve the treatment of a waste with another waste. The preparation method is of low energy consumption, simple preparation process, optimal pH control and no need of acid, which is suitable for large-scale engineering applications.

The invention is a starch-based high water absorptivity resin preparing method, using starch, acrylic nitricle (AN), and 2-acrylamide-2-methyl prophyl sulfonic acid (AMPS) as raw materials, adopting [Mn(H2P2O7)3]3- as initiator, making graft polymerization and saponification, and fast synthesizing starch-based high water absorptivity resin. It makes graft copolymerization on starch and two kinds of monomer raw materials, making them form multielement compound, the initiator is cheap and the modified process can omit medium washing step and AMPS group is added to be able to obviously shorten the synthesis process and time of the final product, reduce production cost and simultaneously also be able to improve the water-absorbing performance of the final product.

The invention provides a negative-thermal expansion and conductive ceramic powder body of Ce-doped zirconium tungstate and a preparation method thereof. The material comprises the component: Zr1-xCexW2O8 (wherein, the x is more than zero and less than or equal to 0.02); the preparation adopts the components ZrOCl2.8H2, 5(NH4)2O.12WO3.5H2O and (NH4)2Ce(NO3)6 as precursors, and uses a hydrothermal synthetic method. The negative-thermal expansion and conductive ceramic powder body of Ce-doped zirconium tungstate of the invention has not only negative thermal expansion, but also conductivity under the temperature of 350 to 700 DEG C. Compared with the traditional sintering method, the hydrothermal synthetic method avoids high-temperature sintering process, thus saving energy and simplifying synthetic technique.

Production of 2-chlorine-5-fluorine-nicotinate and acid is carried out by 2-chlorine-5-fluorine-nicotinate and related carboxylic acid selective dechlorinating, and 2-chlorine-5-fluorine-nicotinate hydrolyzing 2-chlorine-5-fluorine-niacin under the exist of alkaline substances. It can be used for 2-chlorine-5-fluorine-nicotinate and 2-chlorine-5-fluorine-niacin medicine intermediate.

The invention relates to a ceramic positive temperature coefficient (PTC) thermistor of a variable-frequency air conditioner starter and a manufacturing method thereof. The ceramic PTC thermistor belongs to the (Ba1-xCaX) TiO3+TiO2+Y2O3+SiO2+Mn(NO3)2 series. The ceramic PTC thermistor is prepared by 1.022 mol of TiO2, 0.790 to 0.810 mol of BaCO3, 0.179 to 0.185 mol of CaCO3, 0.022 to 0.023 mol of SiO2, 0.0021 to 0.0022 mol of Y2O3 and 50 mass percent of Mn(NO3)2 solution at the concentration of 0.005 ml per weight percent by a one-step synthesis method. The raw materials are reasonable; the production process is simple; in the product, the Curie temperature is between 125 and 135 DEG C, the voltage resistance is more than AC800V, and the resistivity at room temperature is 190 to 480 Omega cm; and the ceramic PTC thermistor is particularly suitable for the variable-frequency air conditioner starter.