76 results about "Glycolates" patented technology

A catalyst for hydrogenated synthesis of glycol with oxalate and a preparation method for the catalyst belong to the glycol preparation technical field. The catalyst of the present invention uses the copper metal as the main active component, and zinc as the promoter, and is manufactured with the method of deposition. A carrier of the catalyst is the modified silica sol. The select content of the copper metal is 5 to 45 percent of the carrier weight, and the optimal content of the copper metal is 10 to 40 percent. The content of zinc metal is 0.1 to 15 percent of the carrier weight, and the optimal content of zinc metal is 1 to 8.0 percent. The select specific surface area of the carrier is 90-350m²/g, and the optimal is 150-300m²/g. Proven by experiments, the catalyst is provided with the very high reaction activity and glycollate selectivity in the reaction to synthesize glycollate with oxalate and hydrogen Moreover, the catalyst is provided with the long usable life and the stable reaction performance, and can be easily controlled.

Absorbable polyurethanes, polyamides and polyester urethanes prepared from at least one compound selected from:

or the diamines and diisocyanates thereof, wherein each X represents a member independently selected from —CH₂COO— (glycolic acid moiety), —CH(CH₃)COO— (lactic acid moiety), —CH₂CH₂OCH₂COO— (dioxanone), —CH₂CH₂CH₂CH₂CH₂COO— (caprolactone moiety), —(CH₂)_yCOO— where y is one of the numbers 2, 3, 4 or 6-24 inclusive, and —(CH₂CH₂O)_z′CH₂COO— where z′ is an integer between 2 and 24, inclusive; each Y represents a member independently selected from —COCH₂O— (glycolic ester moiety), —COCH(CH₃)O— (lactic ester moiety), —COCH₂OCH₂CH₂O— (dioxanone ester), —COCH₂CH₂CH₂CH₂CH₂O— (caprolactone ester), —CO(CH₂)_mO— where m is an integer between 2, 3, 4 or 6-24 inclusive, —COCH₂O(CH₂CH₂O)_n— where n is an integer between 2 and 24, inclusive; R′ is hydrogen, benzyl or an alkyl group, the alkyl group being either straight-chained or branched; p is an integer between 1 and 4, inclusive; and Rn represents one or more members selected from H, alkoxy, benzyloxy, aldehyde, halogen, carboxylic acid and —NO₂, which is attached directly to an aromatic ring or attached through an aliphatic chain. Absorbable polymers prepared from these compounds are useful for drug delivery, tissue engineering, tissue adhesives, adhesion prevention and other implantable medical devices.

The invention relates to a poly(terephthalate glycol ester-CO-glycolate) copolyester and a preparation method thereof. The poly(terephthalate glycol ester-CO-glycolate) copolyester has the melting point of 200-250 DEG C, has the intrinsic viscosity of 0.6-1.2 dL/g, and is biodegradable. The preparation method is simple; raw materials are low in cost; the product performance has a smaller difference from that of PET (polyethylene terephthalate); and the copolyester can be applied to preparation of fibers, films, sheets, bottles and other plastic products.

The invention discloses a process method for preparing glycolide from glycolate, and belongs to the technical field of chemical products. The method comprises the following steps: carrying out primaryreaction on reaction raw materials glycollate and a catalyst in a pre-polymerization kettle; transferring the obtained mixture into a final polymerization kettle connected with a pre-polymerization kettle; oligomers formed by the reaction in the final polymerization kettle flow into a depolymerization kettle to be subjected to a depolymerization reaction; enabling a part of the crude product glycolide obtained in the depolymerization kettle directly to directly flow into a crude product storage tank; and feeding the rest of depolymerized materials into the wiped film evaporator by a circulating pump; separating out a crude product glycolide and other materials in the wiped film evaporator, collecting the crude product glycolide in a crude product storage tank, enabling the other materialsto flow into the depolymerization kettle again for further depolymerization reaction; and purifying the crude product glycolide collected in the crude product storage tank through a melting crystallizer to obtain a pure product glycolide. The polymerization process designed by the invention is divided into two steps, so that the production energy consumption is effectively reduced; meanwhile,, bymeans of the thin-film evaporator, side reactions such as further polymerization and coking caused by the fact that the oligomer stays in the depolymerization kettle for a long time are avoided.

The invention relates to a method for increasing selectivity of glycollic acid ester. The technical problem of low selectivity of the glycollic acid ester in the prior art is solved. The method comprises the following steps of: taking oxalate as a raw material, and contacting the raw material with a copper-containing oxide catalyst under the conditions of reaction temperature at 100-210 DEG C, weight hourly space velocity at 0.2-5 per hour, mole ratio of hydrogen to ester at (10-100):1 and reaction pressure at 0.5-6.0MPa, thereby generating a reaction effluent containing the glycollic acid ester, wherein the reaction is started by the copper-containing oxide catalyst under oxide state, and on the basis of weight part of the catalyst, the copper-containing oxide catalyst comprises 10-60 weight parts of copper and copper oxide components. According to the technical scheme, the problem is more efficiently solved. The method is suitable for the industrial production for increasing the yield of glycollic acid ester.

The invention relates to a catalyst for production of hydroxyacetic acid ester by oxalate through hydrogenation, which mainly solves the technical problem of low selectivity of hydroxyacetic acid ester in hydrogenated products in the prior art. The catalyst comprises the following components as per parts by weight: 5 to 80 parts of active component, 0 to 40 parts of assistant and 1 t0 30 parts of carriers, wherein the active component is copper, oxide of copper of copper mixture; the assistant is at least one of zinc, lanthanum, barium, nickel or iron or oxide of zinc, lanthanum, barium, nickel or iron; and the carrier is a complex carrier chosen from alumina and silicon oxide, and the weight ratio of the alumina and silicon oxide is 0.01 to 30:1. The catalyst for production of hydroxyacetic acid ester by oxalate through hydrogenation can solve the problem well, and can be used for industrial production of hydroxyacetic acid ester.

Disclosed are quaternary ammonium salts containing non-halogen anions such as carbonates, bicarbonates, phosphates, glycolates and mixtures thereof as conversion coatings or additives imparting anti-corrosive properties to paints. The invention relates to a method for inhibiting the corrosion of metal surfaces by applying a composition containing one or more quaternary ammonium carbonate or bicarbonate. The disclosure is also directed to anti-corrosive coatings for metal substrates containing these compounds and to metal substrates having these anticorrosive coatings.

The invention relates to a method for producing glyoxylate through oxidation of glycollate. The invention mainly aims to overcome the problem of low yield of glyoxylate in the prior art. The method provided by the invention comprises a reaction step of contacting a nitrogen oxide and oxygen-containing gas with glycollate to produce glyoxylate. A catalyst used in the invention comprises the following components by weight: a) 0.5 to 30 parts of at least one active component selected from a group consisting of iron and iron oxides; b) 0 to 10 parts of an auxiliary agent which is at least one metal selected from a group consisting of group IA or group IIA elements or oxides thereof; and c) 70 to 99 parts of a carrier. With such a technical scheme, the above problem is overcome, and the method is applicable to industrial production of glyoxylate through oxidation of glycollate.

The invention relates to a method for producing glycolic acid ester through adding hydrogen in oxalic ester, which mainly solves the technical problem in the prior art that the selectivity of the glycolic acid ester is low in a hydrogenated production. The invention adopts the technical scheme that under conditions that the reaction temperature is 100-250 DEG C, the weight space velocity is 0.2-5 h<-1>, the molar ratio of hydrogen to ester is (10-100):1, and the reaction pressure is 0-6.0 MPa, raw materials, namely the oxalic ester, are in contact with a catalyst to generate an effluence containing the glycolic acid ester, wherein the catalyst, in parts by weight, comprises 5-80 parts of active component, 0-40 parts of additive and 1-90 parts of carrier. Due to the adoption of the technical scheme, the problem is better solved, and the method can be used in the industrial production of glycolic acid ester.

Disclosed is a process for producing glycolate ester oligomers. The process comprises reacting ethylene glycol and glycolic acid to produce a stream of glycolate ester oligomers and glycolic acid oligomers while simultaneously removing water. The stream of glycolate ester oligomers and glycolic acid oligomers has a low concentration of water and glycolic acid-ends, and thus is useful in a subsequent hydrogenation reaction to produce ethylene glycol.

The invention discloses a biodegradable tissue engineering urethral stent and a preparation method thereof. The biodegradable tissue engineering urethral stent is made of a copolymer formed by polylactic acid-co-glycolate, polycaprolactone and a solubilizer according to the weight ratio of 70 to 30 to (2-10). The preparation method of the biodegradable tissue engineering urethral stent comprises the following steps of a) blending preparation of a modified material solution, b) medical image processing and modeling, c) 3D template printing and d) stent preparation. PLGA and PCL biodegradable polymers are subjected to solution co-mixing modification, and triethyl citrate is added as the solubilizer, and the blending ratio and the content of the solubilizer are adjusted, so that the toughnessof the modified material is relatively and greatly improved while the flexibility and the tensile strength are kept; and based on a 3D printing technology and in combination with medical image data and software processing, a soluble template can be printed for the focus of a patient, and the personalized tissue engineering urethral stent is prepared.

The invention relates to a preparation method of fluid catalyst for production of hydroxyacetic acid ester by oxalate through hydrogenation, which mainly solves the problem of low hydroxyacetic acid ester selectivity in hydrogenated products in the prior art. The preparation method comprises following steps: (a), preparing required mixed nitrate solution and sodium carbonate solution of copper element and auxiliary agent element; (b), performing coprecipitation to the required mixed nitrate solution and sodium carbonate solution at the temperature of 50 to 90 DEG C, continuously stirring during coprecipitation, and ensuring that the PH value ranges from 5 to 9 when the coprecipitation is ended; (c), washing the precipitated slurry with deionized water repeatedly, and adding a carrier and an adhesion agent for pulping until no Na<+> ion is caused; (d), performing spray forming as per required particle size: the average diameter of catalyst particles is 50 to 300 micrometers, and the catalyst particulars are spheroidal; (e), drying for 4 to 20 hours at the temperature of 80 to 120 DEG C, and roasting for 2 to 8 hours at the temperature of 300 to 550 DEG C. The preparation method solves the problem better and can be used for industrial production of hydroxyacetic acid ester.

The invention discloses a metal-phase carrier-loaded type catalyst, and a preparation method and application thereof. The metal-phase carrier-loaded type catalyst is composed of a metal-phase carrier, and palladium and gold or palladium-gold which are loaded on the carrier, wherein the palladium and the gold or the palladium-gold in the metal-phase carrier-loaded type catalyst has the following contents by weight percentage: the content of the palladium by weight percentage is 0.1 to 2.0%; (2) the content of the gold by weight percentage is 0.1 to 3.0%; or (3) the content of the palladium-gold by weight percentage is 0.1 to 5.0%. The metal-phase carrier-loaded type catalyst can be used as a catalyst in the reaction of hydrogenation synthesis of ethylene glycol or/and glycolate from dimethyl oxalate.

The invention relates to a method for producing ethylene glycol from formaldehyde. The method comprises the following steps: carrying out a carbonylation reaction process on formaldehyde, CO and a solvent under the action of an acidic catalyst to generate a glycollic acid-based product, then, carrying out an esterification reaction process on the glycolic acid-based product and an esterification agent alcohol to generate glycolate, and finally, hydrogenating glycolate to generate ethylene glycol. The method has the beneficial effects that the technological process is short, the investment costis low, the pressure of a formaldehyde carbonylation reaction is reduced, the yield of glycollic acid is increased, and then the yield of ethylene glycol in the whole technological process is increased.

The invention provides a diester structure monomer, a preparation method thereof and application of an ArF photoresist formula. The preparation method of the diester structure monomer comprises the following steps of: dissolving glycolate in a reaction solvent to prepare a glycolate solution; mixing the glycolate solution with triethylamine in a protective atmosphere, and performing cooling to form a mixed solution; and keeping the protective atmosphere unchanged, and adding methacryloyl chloride into the mixed solution to carry out esterification reaction, thereby generating the diester structure monomer. According to the preparation method of the diester structure monomer, the generated diester structure monomer has a diester long side chain and a group with small size and high acid sensitivity; resin synthesized by the diester structure monomer is endowed with better adhesive force and film-forming property, deprotection reaction efficiency and plasticity, and the hardness and brittleness of the resin are improved. And the prepared diester acid protection structure monomer has the advantages of higher yield, low by-product content and easiness in separation and purification.

The invention discloses a system and a method for efficiently synthesizing glycolide. The system comprises a falling film reaction unit, wherein the falling film reaction unit comprises a falling film reactor, a vaporizing chamber, a circulating pump, a condenser, a collecting tank and a vacuum pump. The method comprises the following steps: adding glycollic acid/glycollate liquid and a catalyst into a gasification chamber through a feeding pipeline, starting a circulating pump, enabling the material to circularly flow, carrying out dehydration/dealcoholization condensation on the glycollic acid/glycollate liquid entering a falling film reactor in the falling film reactor to obtain a glycollic acid oligomer, and further depolymerizing to obtain glycolide gas; enabling the glycolide gas and the unreacted liquid-phase material to enter a vaporizing chamber for gas-liquid separation, enabling the liquid-phase material to enter the falling film reactor again through a circulating pump for the next round of reaction, and enabling the gas to enter a condenser to be condensed and then flow into a collecting tank; and enabling the vacuum pump to adjust the system pressure, so that the reaction is carried out under a negative pressure condition. The system disclosed by the invention is used for synthesizing glycolide and has the advantages of low reaction pressure, accurate temperature control, low gas mass transfer resistance and the like.