753 results about "Propanediol" patented technology

The invention discloses a supported nickel catalyst for preparing 1, 3-propylene glycol through hydrogenation of 3-hydroxypropionaldehyde as well as a preparation method and application of the supported nickel catalyst, and relates to the technical field of catalysts. The modified long-chain multi-carbon inducer is used, and a special long-chain molecular structure and a branched chain group of the inducer can effectively and selectively adsorb and occupy a micropore impregnation site; the preparation method has the beneficial effects that more active component nickel species are obviously promoted to be dispersed in main reaction confinement spaces such as mesopores and macropores and interact with the carrier to form effective active sites, and active component steeping liquor is inhibited from entering micropore channels due to capillary action; the active site failure caused by agglomeration of nickel species in micropores in the subsequent drying and roasting process of the catalyst precursor is avoided, the efficient and directional reaction is ensured, the generation of by-products is greatly reduced, the pressure is relieved for the subsequent product rectification separation, and the final product purity is improved. The catalyst provided by the invention can still keep an excellent catalytic effect when the air speed of a 3-hydroxypropionaldehyde solution is increased to 6.5 h <-1 >.

The present invention relates to the field of polyurethane materials and particularly to a temperature-induced color-changing vehicle film and a preparation method therefor. The method of the present invention comprises: firstly, using polyurethane to wrap vanadium dioxide powder to obtain color-changing microcapsules; then using 1,1,1,3,5,5,5-heptamethyltrisiloxane and 3-allyloxy-1,2-propanediol as raw materials to synthesize an organosilicon-modified diol, and enabling trimellitic anhydride to react with toluene diisocyanate to synthesize a dicarboximide compound; enabling the organosilicon-modified diol and the dicarboximide compound to undergo an esterification reaction and a polymerization reaction to obtain an organosilicon-modified imide polyester diol; then mixing the organosilicon-modified imide polyester diol with polytetrahydrofuran ether glycol 2000, and then enabling the mixture to react with toluene diisocyanate to obtain a polyurethane elastomer; and mixing the polyurethane elastomer, the color-changing microcapsules, a silane coupling agent, a plasticizer, an antioxidant, and an ultraviolet light absorber, followed by melt extrusion and blow molding into a film, so as to obtain the temperature-induced color-changing vehicle film.

The application discloses a thickened oil viscosity reducer for a main viscosity contribution component of colloid and a preparation method thereof. The thickened oil viscosity reducer comprises the following components in percentage by weight: diethylene glycol methyl ether 25-35%, propylene glycol formate 15-25%, dispersant 5-8%, chelating agent 2-4%, anti-coking agent 0.5-1%, anti-swelling agent 1-2% and corrosion inhibitor 1-2%; and the balance is water. The application is a polar + non-aromatic hydrocarbon solvent system; completely avoids high-risk substances such as nonylphenol polyoxyethylene ether, petroleum sulfonate sodium and organic chlorine; is designed in pertinence and can effectively inhibit metal-induced asphaltene bridging; can withstand working conditions from normal temperature to 250 DEG C and up to 300 DEG C; thermal stability is significantly enhanced, and residual carbon after aging is lower than 8%; viscosity reduction efficiency is higher; the system is more stable, flexible in compounding and suitable for field construction.

The invention discloses a novel compound rapid surface anesthetic and a preparation method thereof, and belongs to the field of pharmaceutical preparations. According to the anesthetic, core anesthetic components of lidocaine and tetracaine are compounded with propylene glycol-laurocapram synergistic penetration enhancer, menthol auxiliary penetration enhancer, carbomer 980 gel matrix, triethanolamine pH regulator, glycerol humectant, panthenol soothing agent, purified water and the like, a surface smearing agent is prepared through a specific process, and the anesthetic can be administered in combination with an iontophoresis technology. Compared with the existing surface anesthetic for the cosmetic surgery, the surface anesthetic disclosed by the invention solves the problems of slow effect taking and poor effect, can realize rapid penetration of local skin, has short anesthesia effect taking time, long duration and good effect, has no obvious irritation to the skin, has good product stability, can effectively reduce the drug toxicity, and has a good application prospect. The device is suitable for surface anesthesia of non-surgical medical beauty items such as skin beauty, laser treatment and water-light micro-needles.

The invention discloses a method for preparing 1, 3-propylene glycol by hydrating and hydrogenating acrolein, which comprises the following steps: carrying out hydration reaction by taking an acrolein aqueous solution as a raw material and taking acylated and aminated modified polystyrene resin as a catalyst; carrying out flash evaporation or gas stripping on the product after the reaction to remove acrolein, condensing and recovering the removed acrolein, and carrying out hydrogenation reaction on the acrolein-removed mixed solution serving as a hydrogenation raw material on a metal catalyst; and after the reaction is finished, performing flash evaporation on the product to remove water and light components, and performing vacuum rectification to obtain a high-purity 1, 3-propylene glycol product. According to the method, the modified resin is used for catalyzing the acrolein hydration reaction, the overall yield of the 1, 3-propylene glycol can be increased, the catalyst modification process is simple, the cost is low, the additional value of the final product is high, and the method is suitable for industrial production.

The invention belongs to the field of chemical engineering, and relates to a process device and method for continuously synthesizing glycidyl (3-chloro-1, 2-propylene glycol and sodium hydroxide (hereinafter referred to as NaOH) as raw materials). The device comprises a raw material feeding pump, a heat exchanger, a micro-reactor, a delay tube reactor 1, a neutralization micro-reactor and a delay tube reactor 2 which are sequentially in fluid communication through pipelines, the heat exchangers are divided into two groups, one group is used for heat exchange of 3-chloro-1, 2-propylene glycol solution, and the other group is used for heat exchange of alkaline solution. According to the method, a 3-chloro-1, 2-propylene glycol solution and a sodium hydroxide solution (NaOH) are adopted as raw materials, glycidol is continuously prepared through a microchannel reactor, on the basis, an acid-base neutralization reaction can be carried out in situ according to needs to remove redundant alkali, redundant heat generated by the acid-base neutralization reaction is absorbed through a low-temperature material, and energy consumption is reduced; the product is analyzed by gas chromatography, and the generated glycidol does not have hydrolysates or auto-polymerization products, so that the product selectivity is higher.

The invention relates to the technical field of biodegradable high polymer materials, in particular to a tear-resistant high-barrier biodegradable mulching film and a preparation method thereof, and the tear-resistant high-barrier biodegradable mulching film is prepared from the following raw materials in parts by weight: 60-90 parts of poly (butylene adipate-co-terephthalate); 10 to 40 parts of poly (propylene carbonate); 0.5-5 parts of a plasticizer; 0.05 to 0.3 part of a cross-linking agent; 0.1 to 10 parts of talcum powder; 0.1 to 2 parts of a lubricant; 0.1-1 part of an anti-blocking agent; 0.1 to 1 part of an antioxidant; 0.1 to 1 part of an anti-ultraviolet agent; 0.1-1 part of a light stabilizer; 0.1 to 1 part of an anti-hydrolysis agent; 0.1-1 part of a nucleating agent; the plasticizer is poly (1, 2-propylene glycol adipate); and the cross-linking agent is 1, 4-bis (tert-butylperoxy) diisopropyl benzene. The film has good mechanical properties and water vapor transmission amount, can be completely biodegraded, and has good aging resistance.

The invention relates to a double-self-repairing hydroxyl acrylic coating and a spraying process thereof, and belongs to the technical field of coatings. Comprising 50 to 60 parts of a hydroxy acrylic resin-furan modified copolymer, 5 to 10 parts of a maleimide compound, 3 to 8 parts of propylene glycol methyl ether acetate, 5 to 10 parts of dimethyl carbonate, 5 to 8 parts of polyurethane microcapsules, 5 to 7 parts of carbon black, 2 to 5 parts of modified titanium dioxide, 0.8 to 1.2 parts of a modified polyether siloxane leveling agent and 0.2 to 0.4 part of an organic bismuth-zinc composite drier. 2 to 5 parts of fumed silica; and 1 to 2 parts of nano montmorillonite. The paint provided by the invention can form a uniform and continuous coating on the surface of a base material. When the coating is damaged by scratches and the like, self-repairing can be achieved through double mechanisms. According to the spraying process, the polyurethane microcapsules and the matrix resin are separately mixed, and breakage caused by direct mixing of the microcapsules and the resin can be effectively avoided.

The invention discloses a special ergothioneine-containing skin repair hydrogel for pets and a preparation method of the special ergothioneine-containing skin repair hydrogel, and belongs to the technical field of pet skin care hydrogels. The invention relates to a skin care product which comprises the following components in parts by weight: 1.6-3.8 parts of a functional active component consisting of ergothioneine, quaternized chitosan and oat beta-glucan, 0.15-0.35 part of a cross-linking agent, 5-10 parts of 1, 3-propylene glycol, 5-10 parts of glycerol, 0.2-0.5 part of a preservative and the balance of water, totaling 100 parts. Through precise compatibility of functional active components and synergistic construction of the ionic cross-linked gel matrix, systematic integration of three effects of oxidation resistance, bacteria resistance and healing promotion is achieved, and the technical problems that an existing pet skin care product is single in function, insufficient in synergy and limited in repairing effect are solved.

The invention discloses a bio-based modified high polymer material and a preparation method thereof, and relates to the technical field of high polymer materials. When the bio-based modified high polymer material is prepared, firstly, lignin reacts with terephthalaldehyde to prepare formylated lignin; carrying out multi-component reaction on the aldehyde lignin to obtain modified lignin; the preparation method comprises the following steps: reacting 4-mercaptophenylboronic acid with 1-mercaptoglycerol to prepare a dimercaptoborate cross-linking agent; the preparation method comprises the following steps: reacting isophorone diisocyanate with polytetrahydrofuran ether glycol, and then reacting with a flame-retardant chain extender, 1, 2-propylene glycol and hydroxyethyl methylacrylate to prepare modified polyurethane; and mixing the modified polyurethane, the modified lignin and a dimercaptoborate cross-linking agent, casting and curing to obtain the bio-based modified high polymer material. The bio-based modified high polymer material prepared by the invention has the advantages of flame retardance, antibacterial property, aging resistance, self-repairing property, repeatable processing and high mechanical strength.

The invention relates to a method for producing 1, 3-propylene glycol by fermenting recombinant Escherichia coli, which comprises the following steps: (1) a fermentation growth stage: enabling the recombinant Escherichia coli to grow in a culture medium and inducible expression of an enzyme capable of regulating the production of the 1, 3-propylene glycol; and (2) fermentation metabolism stage: cells of recombinant escherichia coli obtained by centrifuging the fermentation liquor obtained in the fermentation growth stage convert substrate glycerol into 1, 3-propylene glycol in a nitrogen-source-free culture medium. According to the method disclosed by the invention, the engineering bacteria are subjected to independent two-stage fermentation metabolism, so that the growth of the bacteria is limited and the activity of the bacteria is kept during biotransformation, and the mass conversion rate from glycerol to 1, 3-propylene glycol is remarkably improved compared with that of the existing method.

The invention relates to the field of Karstedt catalysts, and discloses a stable-structure Karstedt catalyst for silane modified polyether synthesis, and the stable-structure Karstedt catalyst is prepared from the following raw materials in parts by weight: 2-4 parts of a Karstedt catalyst, 5-8 parts of a polyether siloxane block copolymer, 1-3 parts of nano silicon dioxide, 0.5-1.5 parts of triphenylphosphine, 20-25 parts of propylene glycol monomethyl ether and 0.5-1.0 part of an organosiloxane coupling agent. A polyether siloxane block copolymer is introduced into a Karstedt Catalyst system, and a flexible coating layer is formed outside a catalytic center by utilizing molecular compatibility of a silicon-oxygen chain segment of the polyether siloxane block copolymer and a platinum ligand, so that the exposure degree of the platinum center is remarkably reduced, interference of moisture and polar impurities in air is effectively inhibited, and the catalytic activity of the catalyst is improved. Therefore, the oxidation resistance and the storage stability of the catalyst are improved.

An absorbent retail paper product made up of cellulose fibers, and having a 1,3-dichloro-2-propanol concentration of non-detected amounts to 50 ppb as measured using the AOAC Official Method 2000.0150, a 3-monochloro-1,2 propanediol concentration of non-detected amounts to 1000 ppb as measured using the AOAC Official Method 2000.0150, a polyaminoamide-epihalohydrin concentration of non-detected amounts to 0.09% as measured by an “Adipate test”, and a cross direction wet strength of 80 to 200 n / m, wherein all of the cellulose fibers contained in the absorbent paper product are non-synthetic, cellulose fibers and the absorbent paper product is substantially free of formaldehyde.

The application discloses an EBR solvent and a rectification preparation process thereof, and belongs to the technical field of semiconductor material processing; wherein the EBR solvent comprises the following components in percentage: 95-98% of propylene glycol methyl ether acetate and 2-5% of propylene glyyl methyl ether. The EBR solvent is prepared by rectification recovery of waste liquid generated in a dilution cleaning process, and the main steps are as follows: S1, sedimentation filtration: filtering solid impurities in the waste liquid; S2, preliminary water removal: removing part of water in the filtered waste liquid through a common distillation tank to obtain primary waste liquid raw material; S3, feeding: introducing the primary waste liquid raw material into a rectification tower for intermittent distillation purification; S4, water removal: removing water in the primary waste liquid raw material by using an extractant; S5, extractant reflux; S6, extractant extraction: after the water is removed, the extractant is extracted; and S7, EBR solvent extraction. The application solves the problem that the purity of the effective component EBR solvent in the photoresist cleaning waste liquid is not high, and the recycling effect is poor.

The invention discloses a preparation method of plant-based polyester fibers, and relates to the technical field of high polymer materials. When the plant-based polyester fiber is prepared, firstly, phosphorus-modified dopamine is synthesized by taking dopamine hydrochloride and sodium hypophosphite as raw materials; carrying out copolymerization on the phosphorus-modified dopamine, terephthalic acid, ricinoleic acid and 1, 3-propylene glycol to prepare modified plant-based polyester; the preparation method comprises the following steps: synthesizing 2-bornyl-4, 6-dichloro-1, 3, 5-triazine from aminated carbon nanotubes, further synthesizing 2-bornyl-4, 6-dichloro-1, 3, 5-triazine from L-borneol and 2, 4, 6-trichloro-1, 3, 5-triazine, reacting the 2-bornyl-4, 6-dichloro-1, 3, 5-triazine with the aminated carbon nanotubes, and modifying with allylamine to obtain modified carbon nanotubes; finally, the modified plant-based polyester, the modified carbon nanotubes and auxiliaries are subjected to blending extrusion, melt spinning and treatment through copper nitrate and ascorbic acid, and the plant-based polyester fiber is prepared. The plant-based polyester fiber prepared by the invention has excellent antibacterial property, flame retardant property and mechanical property.

The invention relates to a method for preparing dihydric alcohol by hydrogenolysis of polyhydric alcohol, the hydrogenolysis process of the polyhydric alcohol is carried out in the presence of a supported catalyst, the catalyst carrier is formed alumina, and the active component is Pt metal and an auxiliary agent A thereof; the auxiliary agent A is one or more than two of Mo, Fe, La, Ce, Sn, Zr, Zn, W, Al, Ga, Mn, Nd and Ta, and the loading capacity of the auxiliary agent A is 0.01%-15% by mass of Al2O3. Compared with the prior art, the selectivity of 1, 3-propylene glycol prepared by hydrogenolysis of glycerin and the like can be improved, the glycerin conversion rate can be increased, the reaction pressure window can be widened, and the stability can be improved.

The invention relates to the technical field of polyester degradation, in particular to a selective depolymerization method of polyester in a polyester composite material. The selective depolymerization method comprises the following steps: carrying out a depolymerization reaction on a polyester composite material, a cosolvent, a depolymerization agent and a basic catalyst at normal pressure and a temperature not higher than 65 DEG C, the cosolvent is at least one of an ethylene glycol diether compound, a propylene glycol diether compound and an isobutyl ketone compound. According to the selective depolymerization method, an ethylene glycol diether compound, a propylene glycol diether compound and an isobutyl ketone compound are used as cosolvents, a depolymerization agent is used as a methylation reagent, and directional polyester depolymerization of a polyester composite material can be realized at normal pressure and the temperature not higher than 65 DEG C; when the polyester material is degraded, the non-polyester material is basically not degraded or depolymerized, and the selective depolymerization and separation of the polyester composite material such as a polyester blended fabric can be realized.

The invention discloses a method for detecting anions in a phlegm-heat-clearing injection, the detection method comprises the following steps: a test solution and a reference solution are taken for detection, the phlegm-heat-clearing injection is composed of scutellaria baicalensis, bear gall powder, cornu gorais, honeysuckle, fructus forsythiae and propylene glycol; chromatographic conditions of the detection are as follows: an anion exchange chromatographic column is adopted, an eluent is an acid aqueous solution, an alkali aqueous solution and / or a buffer salt aqueous solution, the flow velocity is 0.1-2.0 ml / min, the column temperature is 20-40 DEG C, a detector is an electrical conductivity detector, the detection mode is suppression electrical conductivity detection, and the sample size is 10-40 [mu] l; and obtaining the content information of the anions in the phlegm-heat clearing injection according to the detection result. The method disclosed by the invention is simple, convenient, efficient and rapid, and provides a theoretical basis for the quality control of the phlegm-heat clearing injection and the deep research of a pharmacodynamic material basis by detecting the content of the anions.

This skin cosmetic offers superior comfort upon application, effectively removes pore impurities when wiped off, and maintains a pore-minimizing effect even after wearing a mask. [Solution] A phenoxyethanol-free skin cosmetic is provided, characterized by containing (A) 1 to 20% by mass of 1,3-propanediol, (B) 0.5 to 4% by mass of 1,2-pentanediol, (C) 0.01 to 0.5% by mass of glycerin mono-2-ethylhexyl ether, and (D) 0.0001 to 0.1% by mass of citrus extract on a solid content basis.

The application provides a low pour point nonionic surfactant and a preparation method thereof, which is composed of the following raw materials in parts by weight: C13 isomeric fatty alcohol polyoxyethylene ether 18-30 parts, reverse EO / PO block copolymer 10-20 parts, sodium diisooctyl sulfosuccinate 1-7 parts, sodium dodecyl sulfonate 1-5 parts, glyceryl laurate 1-5 parts, isopropyl alcohol 5-10 parts, and propylene glycol 1-5 parts; the formula is constructed based on a nonionic surfactant as a main body, ion surfactants and additives are introduced, and the system is optimized, so that a low pour point nonionic surfactant with excellent adsorption capacity and decontamination capacity is obtained.

The present application relates to the field of frother, in particular to a kind of copper flotation collector frother and preparation method thereof, by weight parts, including the following raw materials: N,N-dibutyl dithiocarbamic acid propyl cyanurate 100-120 parts, O-butyl-N-isobutyl thiopropyl carbamate 12-18 parts, xanthate 12-18 parts, phosphate ester polypropylene glycol ether 15-20 parts, modified betaine 5-8 parts, alcohol ether 3-5 parts, slime inhibitor 1-3 parts, alcohol ether carboxylate 2-5 parts, sorbitan monooleate 0.8-1.2 parts. Through the synergies of each raw material, the collector capacity, selectivity in copper flotation process can be effectively improved, and the reagent stability is good.

The invention discloses a flexible glass cutting fluid and a preparation method thereof, and the preparation method comprises the following steps: S1, adding cellobiose into DMF, then adding chloroacetic anhydride and pyridine, and carrying out a stirring reaction to obtain an intermediate; s2, adding the intermediate into DMF (Dimethyl Formamide), and then carrying out constant-temperature reaction on glycerol monocaprylate, 2-(2-hydroxyphenyl) benzothiazole and triethylamine to obtain a modifier; s3, uniformly mixing a modifier, sodium dioctyl sulfosuccinate and a polyoxyethylene polyoxypropylene block copolymer, so as to obtain a composite surfactant; s4, adding the composite surfactant, the propylene glycol, the defoaming agent, the sterilizing agent and the triethanolamine into the water, and uniformly stirring to obtain the cleaning agent. According to the prepared cutting fluid, the protection effect on a flexible glass base material and a surface functional layer of the flexible glass base material is remarkably improved while the excellent wettability is kept, microcrack generation and surface damage in the cutting process are reduced, and the cutting fluid is particularly suitable for precise glass processing of flexible display devices.

The application relates to a low-eutectic solvent-based gel electrolyte, a preparation method and a zinc-air battery, and belongs to the technical field of metal-air batteries. Choline chloride and 2-methyl-1,3-propanediol are prepared into a deep eutectic solvent, then zinc acetate dihydrate solution, acrylic acid monomer, a crosslinking agent and a photoinitiator are sequentially added, the mixture is uniformly mixed, photopolymerization is carried out, and a low-eutectic solvent-based gel is obtained. The electrolyte is obtained by soaking the gel in a mixed solution of potassium hydroxide and zinc salt. The zinc anode protection capability and the low-temperature adaptability of the gel electrolyte can be improved. The gel electrolyte is assembled into a zinc-air battery together with a zinc electrode and an air electrode, and the cycle life and the operation stability of the battery in a low-temperature environment can be effectively improved.

The invention provides an essence lotion with an anti-aging function and a preparation method thereof, and belongs to the technical field of cosmetics, the essence lotion comprises a phase A, a phase B, a phase C and a phase D, wherein the phase A consists of glyceryl distearate, jojoba oil and vitamin E; the phase B is prepared from deionized water, glycerol, 1, 3-propylene glycol, methylparaben and polyoxyethylene sorbitan monooleate; the phase C is a citric acid solution; and the phase D consists of exosomes from four fruit sources of blueberries, pomegranates, lemons and grapefruits. According to the technical scheme, exosomes from blueberries, pomegranates, lemons and grapefruits are scientifically compounded, an anti-aging network with a synergistic effect is constructed, good stability and biocompatibility are achieved, and many problems existing in traditional anti-aging cosmetic ingredients are solved.

The application discloses an environment-friendly fluorine-free super-hydrophobic coating material and a preparation method thereof, and belongs to the technical field of super-hydrophobic coating materials. The preparation method comprises the following steps: mixing hyperbranched polyurethane, ethyl acetate and propylene glycol methyl ether acetate for 10-20 min, then adding polydimethylsiloxane and octadecyl isocyanate to carry out mixing reaction for 60-80 min, then adding multistage microspheres to carry out ultrasonic treatment for 15-30 min, and then adding Isopar G, isophorone diisocyanate, silane coupling agent KH-560, dibutyl tin dilaurate and triethylenediamine to carry out stirring and dispersion for 30-50 min, so as to obtain the environment-friendly fluorine-free super-hydrophobic coating material. The environment-friendly fluorine-free super-hydrophobic coating material prepared by the application has good super-hydrophobicity, self-repairing function and wear resistance.

The invention discloses a blue copper peptide composition for repairing scars and a preparation method of the blue copper peptide composition, and belongs to the technical field of preparation of biological medicine preparations. The composition is prepared from freeze-dried powder of copper blue peptide, polyquaternium-73, asiaticoside, nicotinamide, polydimethylsiloxane, betaine-propylene glycol ionic liquid and a gel matrix. According to the invention, the blue copper peptide is coated in a permeation enhancing system constructed by the betaine-propylene glycol ionic liquid and the HEPES, so that the enzymolysis loss of the blue copper peptide is reduced, and the biological activity of the blue copper peptide is maintained; a temperature-sensitive gel matrix is constructed by carboxyl esterified modified sodium alginate and poloxamer, the carboxyl esterified modified sodium alginate is prepared by grafting n-butyl alcohol to a hydrophilic main chain of sodium alginate through a Fischer esterification method, the gel matrix is in a liquid state at normal temperature, after the gel matrix is smeared on a scar part, the gel matrix is converted into semi-solid gel under the influence of body temperature, and slow and continuous release of blue copper peptide can be achieved. The traditional Chinese medicine composition has the effect of repairing scars and is suitable for chronic scars needing long-term nursing.

The present disclosure discloses a composition for hair growth comprising Larix europea wood extract, Camellia sinesis leaf extract, Pisum sativum sprout extract, Curcuma longa (Turmeric) callus conditioned media, Hamamelis virginiana (Witch Hazel), Rosmarinus officinalis Leaf Oil, Glycerin, Glycine, Zinc Chloride, Sodium Metabisulfite, Gluconolactone, Sodium Benzoate, Calcium Gluconate, Tetrasodium ethylenediaminetetraacetic acid (EDTA), Saccharide Isomerate, Hyaluronic Acid, Hydrolyzed Hyaluronic Acid, Propanediol, Biotinoyl Tripeptide- 1, Alpha Glucosyl Hesperidin, Caffeine, Hydrolyzed Pea Protein, Polyalkylene Glycol Mono Butyl Ether, Acrylates / C 10-30 Alkyl Acrylate Crosspolymer, Panthenol, Niacinamide, Arginine, PEG-40 Hydrogenated Castor Oil, Ethylhexylglycerin, Phenoxyethanol, and water is added to the composition until the desired volume is achieved. A method for preparing the composition for hair growth is also provided.

A full continuous-flow preparation method of (+)-biotin, including: subjecting a cyclic anhydride and a chiral biphenyl propylene glycol to asymmetric ring-opening reaction to produce a first intermediate, which undergoes selective reduction with a borohydride and cyclization with an inorganic mineral acid to produce (3aS, 6aR)-lactone; subjecting the (3aS, 6aR)-lactone and a sulfenylating reagent to sulfenylation to produce (3aS, 6aR)-thiolactone, which undergoes Fukuyama coupling with a zinc reagent in the presence of a palladium catalyst and elimination reaction in the presence of an inorganic mineral acid to produce an alkenyl valerate compound; subjecting the alkenyl valerate compound to reduction in the presence of a Pd / C catalyst to produce a valerate ester, which undergoes hydrolysis to produce a valeric acid salt; and subjecting the valeric acid salt to debenzylation in the presence of an inorganic mineral acid to produce the target product (+)-biotin.

The present application belongs to the technical field of daily chemical preparation, and particularly relates to a gynecological gel for inhibiting bacteria, regulating microecological balance and tightening vagina and a preparation method thereof. The gynecological gel comprises the following raw materials in mass fractions: 0.5-1 parts of carbomer, 0.04-0.09 parts of sodium hydroxide, 1-3 parts of collagen, 0.01-0.06 parts of sodium hyaluronate, 0.5-1.5 parts of isomaltooligosaccharide, 2-5 parts of propylene glycol, 0.05-0.3 parts of hydroxybenzoic acid methyl ester, 0.02-0.15 parts of hydroxyphenyl ethyl ester, 0.1-1.5 parts of hydrogenated lecithin, 1-6 parts of 1,3-butanediol, 3-5 parts of glycerol, 0.5-1 part of xanthan gum and 70-90 parts of water. The present application uses buckwheat filtrate to prepare collagen, and the active ingredients in the buckwheat filtrate can penetrate the cell membrane of pathogenic bacteria to play an antibacterial role; the collagen can repair the vaginal mucosa barrier and reduce the adhesion and invasion of pathogenic bacteria; therefore, after being compounded with the raw materials such as carbomer, sodium hydroxide, sodium hyaluronate, isomaltooligosaccharide and propylene glycol, the multiple components can synergistically promote the synthesis and repair of collagen fibers and improve the elasticity of tissues.

The invention discloses a method for preparing propylene glycol by hydrogenolysis of glycerol, and belongs to the technical field of propylene glycol preparation. In a hydrogen electrolytic tank, a three-electrode system is adopted, a reference electrode is an Ag / AgCl electrode, a counter electrode is a platinum sheet electrode, a working electrode is a CuAg-TiN electrode, the working electrode and the counter electrode are separated by a proton exchange membrane, and electrolyte is filled; and adding trimethylolpropane as an additive, and adding glycerol at the cathode for reaction to obtain the 1, 3-propylene glycol. According to the method, reaction is realized at normal temperature and normal pressure, hydrogen is not used, and active hydrogen generated by in-situ electrolysis of water reacts with glycerol, so that high-selectivity production of propylene glycol is realized, and the whole reaction process is mild in condition, low in cost and good in stability.