1180 results about "Ketene" patented technology

The invention relates to a modified AKD (Alkyl Ketene Dimer) neutral sizing agent which is a milk white liquid in appearance. The modified AKD neutral sizing agent comprises the following main materials: AKD, starch, paraffin, high molecular dispersant and other assistant materials. The modified AKD neutral sizing agent is mainly used for sizing paper pulp and improving the water resistance and impermeability of paper in the paper-making production process, and the consumption for every ton of paper is 10-20kg. Compared with like products, the quickly-cured modified AKD neutral sizing agent has the following advantages: (1) effective ingredient particles of the product are finer and more uniform and can be cured more tightly, the product has a longer quality guarantee period, and convenience is provided for transportation and storage; (2) the product is applicable to neutral paper pulp and can no longer result in the production of acidic paper-making sewage, thereby being beneficial to environmental protection; (3) the use effect of the product can act quickly, and the curing time is extremely short, thereby facilitating the effect monitoring and quality control in use, improving the production efficiency and enhancing the yield of paper; and (4) the consumption of the product is lower than that of other like products, thereby reducing the cost of production materials and improving the economic benefits of customers.

The invention discloses a food wrapping paper and a production method thereof. Poplar chemical mechanical pulp, bleached kraft softwood pulp and bleached kraft hardwood pulp are used as fiber raw materials. Sizing, desanding and degassing, sizing, fine sieving, wire dehydration forming, pressing, pre-drying, surface sizing, post-drying, calendering, coiling, and packaging to form food packaging paper. The present invention uses the surface sizing treatment method to process the product, and adds a starch surface sizing agent to the surface sizing to improve water resistance and adds a small amount of sizing agent alkyl ketene dimer to the surface sizing glue, which can Improve the retention rate, save costs, and make products more cost-effective.

The invention relates to a process for preparing sorbic acid by cleaving the sorbic acid polyester prepared from crotonaldehyde and ketene, the sorbic acid polyester being distilled and the cleavage being catalyzed by an amine, which comprises separating off the amine from the distillation residue by distillation under reduced pressure and at a temperature which is higher than the temperature of the polyester distillation and recovering it.

A filter medium for an air filter, characterized in that it comprises a filter material having a glass fiber as its primary component and an alkyl ketene dimer adhered to the surface of the glass fiber; and a method for producing the filter medium which comprises a step of subjecting a dispersed slurry of a raw material fiber to a wet papermaking to form a wet paper, a step of immersing the wet paper in an aqueous dispersion or solution of the dimer or a liquid mixture of the dimer and a binder resin, or applying or spraying any of the above-mentioned liquids to the wet paper, to thereby allow the dimer to adhere onto the surface of the glass fiber, and a step of drying the resultant wet paper having the dimer adhered thereto. The filter medium exhibits a reduced amount of an out gas generated when it is used with ventilation and also exhibits high water-repellency and satisfactory strength in various applications such as air conditioning of a building and semiconductor manufacturing.

The invention provides a bromide type muscle relaxant, which mainly comprises a method for synthesizing rocuronium bromide, vecuronium bromide, pancuronium bromide and pipecuronium bromide , and is mainly characterized by adopting a ketene as an acylating agent during the process of transforming 5Alpha-androstane -2-alkene-17-alkone to 17-acetoxyl group-5Alpha- androstane-2, and 16-diene, adopting a stress kettle as a reactor when realizing the step of ring-opening and condensation of the 2 Alpha and 3 Alpha-epoxy compound, and adding a solid catalyst and a desiccant in the last step of operation of rocuronium bromide to greatly improve the reaction yield and the quality of products. The technology provided by the invention can shorten the synthesis time of the bromide type muscle relaxant, simplify the operation steps, improve the quality of products and reduce the production cost.

A thermosetting composition having:

• • I. a curable polyester resin containing beta-ketoacetate moieties without vinyl unsaturations; and
  • II. a phenolic resin having at least one methylol group.

The curable polyester resin can be made by reacting a polyester resin with a compound containing a beta-ketoacetate moiety that does not contain a vinyl unsaturation such as alkyl acetoacetate compounds or diketene compounds.

The curable polyester resin can be dispersed in water or dissolved in a solvent and is suitable for waterborne or solventborne coating compositions. Phenolic based crosslinking coating compositions that contain these curable polyester resins cure well with phenolic resin crosslinking compounds.

The invention relates to a cooling method for rectification vacuum pump in ketene dimer production, wherein the method comprises the steps of: placing 25#transformer oil in an oil groove with cooling pipe, when the rectification vacuum pump is operating, pumping the 25#transformer from the oil cooler to the pump for cooling and sealing, combining the ketene dimer taken back from the bottom connected by the rectification vacuum pump to coarse ketene dimer section. The outlet gas of the rectification vacuum pump is pumped in tail gas absorber to spray and absorb ketene dimer. When acid content of circulating recycling liquid reaches 35-50%, the liquid is sent to glacial acetic acid for recycling, and residual carbon dioxide and nitrogen are pumped in the cracking still as fuel. The cooling method of rectification vacuum pump in ketene dimer production utilizes oil to replace water as cooling and sealing of vacuum pump, and uses soft water to absorb gases such as ketene dimer in the vacuum pump, which not only saves a great deal of water reduces emission, but also takes back ketene dimer to save resources and reduce environmental pollution.

The invention provides latex for papermaking. The latex contains starch, oxidants, hydrophobic modifying agents and water, wherein the dosage of the oxidants is 7-10% of the mass of starch; the dosage of the hydrophobic modifying agents is 5-20% of the mass of the starch; the hydrophobic modifying agents are selected from at least one of dodecenyl succinic anhydride, maleic anhydride, epoxy chloropropane, an alkyl ketene dimmer, alkenyl succinic anhydride, a styrene-acrylate copolymer, a silane coupling agent and a titanate coupling agent. The invention also provides a preparation method of the latex for papermaking and a coating containing the latex for papermaking. The problems that the wet strength of finished paper is poor and dusting happens easily because the paper is coated with the starch-based latex for papermaking in existing processes are solved.

The invention discloses a method for preparing amphoteric high molecular base AKD emulsion. The method comprises the following steps: under the function of a cosolvent and a molecular weight regulator, taking vinyl monomers, such as styrene, acrylate, acrylamide, a cation monomer, (methyl) acrylic acid and the like, as a copolymerization monomer and preparing amphoteric saponin-free benzene emulsion by a saponin-free emulsion polymerization method; taking the amphoteric saponin-free benzene emulsion as an amphoteric high molecular surfactant, emulsifying and dispersing a long-chain alkyl ketene multimer (AKD) with excellent hydrophobic property and preparing the AKD emulsion with favorable stability and sizing performance by shearing and dispersing. The invention does not use a small molecular emulsifying agent and cation starch in the preparation process and overcomes the defects of easy bubbling, poor stability, poor sizing effect and the like of the traditional AKD emulsion; the prepared amphoteric high molecular base AKD emulsion has anionic properties and cationic properties and is free from the interference of the anionic impurities of a papermaking wet part system, and the retention rate is greatly enhanced.

Methods using chemiluminescent label compounds and chemiluminescent labeled conjugates are provided. The compounds comprise an acridan ring bearing an exocyclic ketene dithioacetal group and further contain a labeling substituent which permits attachment to compounds of interest. The novel chemiluminescent compounds and labeled conjugates are convenient to prepare, are highly stable, and generate chemiluminescence rapidly on demand. The compounds and conjugates are useful in assays of an analyte in a sample and in assays employing labeled specific binding pairs.

The invention relates to a method of prepared 1,4-butyne glycol complex oxide catalyst with the HZSM-5 carrier and its application. The features are that: used the deionized water to make Cu(NO3)2.3H2O,Bi(NO3)3.5H2O and HNO3 mix into solution by the weight rate of 40-80:30-60:3-8:1. the prepared solution with high solicon molecular sieve (HZSM-5)1-1.5:2 mixing, string, dipping, through drying, grinding, roasting to get HZSM-5 load catalyst. Put the catalyst and formalin solution into the reaction kettle, the oil temperature up to 80-95degree centigrade, put the acetylene gas into reaction kettle process the ketenes and alkyne reaction of formalin. The invention catalyst of HZSM-5 carrier have better thermal stability, high activity, good selectivity, simple preparation method, can use the high condense formalin solution to react, it is suitable for synthetic 1,4-butyne glycol, reduce the treatment energy loss in the industry.

According to the present invention, the oxidation agent uses air or oxygen, or mixture gas of oxygen and inert gas, or other chemical oxidation agent, the reaction pressure is controlled to be 1-10 atm, the temperature being 20-150 deg. C, mu-oxygen single metalloporphyrin or double metalloporphyrin, or their carrier is separately selected as catalyst, or they form composite catalyst along with filtering metallic salts or oxidants, the catalyst concentration being 1-50PPM, reaction time being 0.5-5 hours, thus alpha, beta-enol, alpha, beta-ketene and epoxy compounds are obtained through catalytic oxidation of olefin or cyclomonoolefin.

The present invention discloses a novel synthetic method for F-acrylic acid and a derivative thereof. According to the process, ketene diethyl acetal with a molecular formula (2) CH2=C(OR1)2 is used for preparing 2-fluoride acrylic acid with a molecular formula (1) CH2=CF-CO2R and an ester thereof through a cyclopropane derivative with a molecular formula (3). According to the synthetic method disclosed by the invention, the synthetic method has the characteristics that the process is simple, the operability is high, raw materials used in preparation are cheap and the toxicity is low.

Disclosed is a packing material for a sheet recording material, which contains a paper material comprising an alkyl ketene dimer and cationic starch, the extraction pH of the paper material being within the range of 6.5 to 9.0. The packing material of the present invention suppresses generation of paper dust and prevents occurrence of white spot defect in recorded images on a sheet recording material even when the packing material is not subjected to surface treatment.

The invention discloses base paper for thermal transfer. The base paper is prepared from 100% of chemical pulp through pulping, papermaking, drying and curling. The base paper is characterized in that in the pulping step, 50-100% of bleached chemical staple fibers and 0-50% of bleached chemical long fibers are used and undergo pulp dispersion, pulp cleaning and defibrination to achieve fibrillation in the defibrination process; when chemicals are added, 0-20kg/ton paper of alkyl ketene dimmer, 0-2kg/ton paper of alkenyl succinic anhydrides and 70-500kg/ton paper of filler are added to the wet part and other functional auxiliaries are added according to the conventional quantity demanded; 0-20kg/ton paper of surface sizing agent is added to surface sizing starch; and the front calendering pressure and the rear calendering pressure are 10-30kg/cm in the curling process. The base paper has the advantages of higher bulk, suitability for various dye sublimation ink, no crease despite large width of transfer, good transfer effect, bright pattern colors after transfer and the like.

The invention belongs to the field of chemical production, and provides a method for continuously producing acesulfame potassium, which comprises the following steps: continuously mixing and dissolving sulfamic acid and dichloromethane, continuously neutralizing with a triethylamine solution, introducing the neutralized reaction solution and ketene dimer into a continuous reactor, and carrying outaddition acylation reaction to obtain a DKA reaction solution; sulfur trioxide and solvent micro-mixing: S03, enabling dichloromethane to enter a micro-mixer, so as to prepare a cyclizing agent; cyclization and hydrolysis: continuously feeding the DKA reaction solution and a cyclizing agent into a cyclization microreactor to generate a cyclization reaction solution, and continuously feeding the cyclization reaction solution into a hydrolysis microreactor to obtain an acesulfamic acid reaction solution; enabling the acesulfame acid reaction liquid and dichloromethane to enter continuous extraction equipment, enabling an extracted organic phase and a potassium hydroxide aqueous solution to enter a continuous neutralization reactor to obtain acesulfame acid potassium reaction liquid, and subjecting the acesulfame acid potassium reaction liquid to continuous concentration, continuous crystallization, continuous separation and continuous drying to obtain the acesulfame acid potassium finished product. The process has the characteristics of simple process, low cost, good product quality, continuous whole process and the like.

The present invention discloses a waterproof and damp-proof raw paper dedicated for electronic paper tapes, and a preparation method thereof. The method is characterized in that untwining and fibrillation are carried out on pulp fibers, fibrillation and cutting are further carried out so as to enable a pulp beating degree to reach 45 degree SR to 48 degree SR and a fiber wet weight to be reduced to 5.5 g to 8.0 g; and a water-resistant damp-proof composition is added in each layer, 1.0%-2.5% of the water-resistant damp-proof composition is added in relative to 100 parts of the pulp fibers, the water-resistant damp-proof composition including 0.15+-0.015 % of a wet strength agent PAE, 0.50+-0.05 % of gum rosin or an alkyl ketene dimer (AKD), 0.10+-0.01 % of silicon and fluorine type polymers, and 0.15+-0.015 % of ammonium zirconium carbonate. According to the above method, defibrination treatment is utilized, and a water-resistant damp-proof functional chemical is added in the pulp and coated on the surface of paper, surface water absorption and an edge permeation index of the raw paper are lowered than like products on the market, and water-resistance and damp-proofness of the raw paper are the best.

The invention discloses a method for preparing benzopyran derivative by choline chloride functional ion liquid catalysis. The method comprises the following steps of: carrying out catalytic condensation reaction on aromatic aldehyde, an active methylene compound and ketene dimethyl under normal pressure to obtain the benzopyran derivative by using the functional ion liquid based on choline chloride as the catalyst. The method for preparing benzopyran derivative by choline chloride functional ion liquid catalysis is simple to operate, high in yield, good in reusability of catalytic reaction system, gentle in reaction condition and good in industrial prospect.

The invention discloses a synthetic method for a beta-aminocarbonyl compound, beta-mercapto ketone and beta-alkoxy ketone. In the method, ionic liquid is used as a catalyst, and aza-Michael, sulfa-Michael and oxa-Michael reactions of electron-deficient ketene and a nucleophilic reagent are carried out at room temperature so as to synthesize corresponding compounds. According to the invention, usage amount of the catalyst is small, and the catalyst has the advantages of high catalytic activity, good stability, low corrosivity, cyclical usability, good selectivity of products, simple operation and strong controllability; a substrate has a wide application scope, and good yield is obtained in addition of alcohol compounds with low reaction activity; the reactions are mild; reaction products and the catalyst can be easily separated, and the catalyst can be cyclically used.

The invention discloses a near-infrared photo-thermal dye based on aza-fluoro borane, preparation and application. The photo-thermal dye comprises an electron-donating group containing lone pair electrons and a basic aza-fluoro borane skeleton. The near-infrared photo-thermal dye based on aza-fluoro borane is prepared through steps as follows: (1), ketene synthesis: ketene is prepared from aldehyde ketone by an addition-elimination reaction under the alkaline condition; (2), an addition reaction of ketene and nitromethane; (3), a cyclization reaction; (4), a coordination reaction: a product obtained in the step (3) coordinates with boron difluoride, and a target product is obtained. The photo-thermal dye can be applied to the technical fields of photodynamic therapy and photo-thermal therapy under the guidance of photo-thermal imaging and photo-acoustic imaging, bio-marker and detection and the like.

The invention discloses a grass suppression straw biomass-base degradable mulching film and application. A method for preparing the grass suppression straw biomass-base degradable mulching film includes S1, biologically pretreating straw, to be more specific, compounding phanerochaete chrysosporium and streptomyces rochei, then inoculating the phanerochaete chrysosporium and the streptomyces rochei on the straw, adjusting carbon-nitrogen ratios and moisture contents of material systems and carrying out aerobic fermentation; S2, softening, disassembling and separating straw fibers, to be ore specific, softening the pretreated straw fibers and disassembling the pretreated straw fibers until the fiber lengths are 0.5-2 cm; S3, forming straw biomass-base mulching films, to be more specific, uniformly mixing the straw fibers, wood pulp, methyl celluloses, sodium alginate, gelatin, polyamide epichlorohydrin resin, alkyl ketene dimmers, polyacrylamide, glycerol, alkenyl succinic anhydride grafted starch adhesive and biochar with one another, and carrying out vacuum dehydration, squeezing, drying and forming to obtain the grass suppression straw biomass-base degradable mulching film. The grass suppression straw biomass-base degradable mulching film can be applied to the field of paddy rice seedling raising.