- Covalent Adaptable Networks Using β-Amino Esters as Thermally Reversible Building Blocks
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In this study, β-amino esters, prepared by the aza-Michael addition of an amine to an acrylate moiety, are investigated as building blocks for the formation of dynamic covalent networks. While such amino esters are usually considered as thermally nondynamic adducts, the kinetic model studies presented here show that dynamic covalent exchange occurs via both dynamic aza-Michael reaction and catalyst-free transesterification. This knowledge is transferred to create β-amino ester-based covalent adaptable networks (CANs) with coexisting dissociative and associative covalent dynamic exchange reactions. The ease, robustness, and versatility of this chemistry are demonstrated by using a variety of readily available multifunctional acrylates and amines. The presented CANs are reprocessed via either a dynamic aza-Michael reaction or a catalyst-free transesterification in the presence of hydroxyl moieties. This results in reprocessable, densely cross-linked materials with a glass transition temperature (Tg) ranging from -60 to 90 °C. Moreover, even for the low Tg materials, a high creep resistance was demonstrated at elevated temperatures up to 80 °C. When additional β-hydroxyl group-containing building blocks are applied during the network design, an enhanced neighboring group participation effect allows reprocessing of materials up to 10 times at 150 °C within 30 min while maintaining their material properties.
- Taplan, Christian,Guerre, Marc,Du Prez, Filip E.
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- Second-Generation meta-Phenolsulfonic Acid-Formaldehyde Resin as a Catalyst for Continuous-Flow Esterification
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A second-generation m-phenolsulfonic acid-formaldehyde resin (PAFR II) catalyst was prepared by condensation polymerization of sodium m-phenolsulfonate and paraformaldehyde in an aqueous H2SO4 solution. This reusable, robust acid resin catalyst was improved in both catalytic activity and stability, maintaining the characteristics of the previous generation catalyst (p-phenolsulfonic acid-formaldehyde resin). PAFR II was applied in the batchwise and continuous-flow direct esterification without water removal and provided higher product yields in continuous-flow esterification than any other commercial ion-exchanged acid catalyst tested.
- Hu, Hao,Ota, Hajime,Baek, Heeyoel,Shinohara, Kenta,Mase, Toshiaki,Uozumi, Yasuhiro,Yamada, Yoichi M. A.
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- METHOD FOR PRODUCING UNSATURATED CARBOXYLIC ESTER
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An object of the present invention is to provide a method for producing an unsaturated carboxylic ester, wherein the risk of polymerization blockage is reduced and the required equipment cost and workload involved are kept low while maintaining a high conversion rate in an esterification reaction of unsaturated carboxylic acid. This object can be achieved by a method for producing an unsaturated carboxylic ester, which includes performing an esterification reaction using a reactor packed with a solid catalyst, wherein unsaturated carboxylic acid and alcohol are continuously fed to the reactor from an inlet thereof to form a fluid of the reaction solution in the reactor, and the vaporized organic solvent is continuously fed to the reactor from the inlet or a part near the inlet of the reactor.
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Paragraph 0064-0072
(2021/01/25)
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- Ruthenium(II) oxidase catalysis for C-H alkenylations in biomass-derived γ-valerolactone
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Ruthenium(ii) biscarboxylate oxidase catalysis is a powerful tool for the assembly of functionalized arenes with oxygen as a green oxidant, but this strategy was thus far limited to its use in traditional organic solvents. Herein, we report on a green procedure for the ruthenium(ii) biscarboxylate-catalysed C-H functionalisation in biomass-derived γ-valerolactone as the reaction medium. The oxidase catalysis was characterized by ample substrate scope and proceeded efficiently with oxygen as the sole oxidant. The overall green nature of this C-H-activation methodology is reflected by H2O being the only by-product.
- Bechtoldt, Alexander,Baumert, Marcel E.,Vaccaro, Luigi,Ackermann, Lutz
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supporting information
p. 398 - 402
(2018/02/07)
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- PROCESS FOR PREPARING CARBOXYLIC ACID ESTERS IN THE PRESENCE OF A TITANIUM-CONTAINING CATALYST
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?The present invention relates to a process for preparing carboxylic acid esters, comprising esterification of a carboxylic acid with an alcohol in the presence of a titanium-containing catalyst selected from compounds of a general formula, Tin(OR)x(OR')xOy, wherein n is an integer from 1 to 4; у is an integer from 0 to 6; x can be the same or different and is an integer from 2 to 8; R is a linear or branched C1-C18alkyl, C3-C18cycloalkyl, R' is aryl optionally comprising an electron-donor substituent; or a mixture thereof, with the proviso that if n is 1, then x is 2 and у is 0; and if n>1, then the compounds comprise at least two alkoxy groups and two aryloxy groups. The present invention also relates to a process for preparing carboxylic acid esters, wherein a compound of general formula (I) or (II), wherein q represents an integer of 1 to 4; Y is independently R or R'; or a mixture thereof, with the proviso that the compounds comprise at least two alkoxy groups and two aryloxy groups, is used as a catalyst. The claimed process allows to reduce the amount of a used catalyst and the time of the process duration, while increasing the conversion rate of initial reagents and the yield of a target product.
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Page/Page column 16; 17; 18
(2016/04/09)
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- PROCESS FOR PREPARING 4-HYDROXYBUTYL ACRYLATE
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A process for preparing 4-hydroxybutyl acrylate by transesterifying an alkyl acrylate with 1,4-butanediol in the presence of a dialkyltin oxide such that each of the alkyl groups has 4 to 8 carbon atoms, characterized in that the amount of the dialkyltin oxide is adjusted to 0.00001 to 0.01 moles per one mole of the alkyl acrylate.
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Paragraph 0620; 0621; 0622; 0623; 0624
(2015/04/22)
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- CURABLE COMPOSITION FOR IMPRINT, PATTERNING METHOD AND PATTERN
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A curable composition for imprints, which is excellent in patternability and in line edge roughness, is provided. The curable composition for imprints comprises at least one kind of polymerizable monomer (A) and at least one kind of photopolymerization initiator (B). The polymerizable monomer (A) comprises at least two fluorine-containing groups selected from a fluoroalkyl group and a fluoroalkylether group and each of two of the fluorine-containing groups is connected with each other through a linking group having at least two carbon atoms.
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- Process for producing acrylic ester
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A process for producing an acrylic ester with excellent economic efficiency, which can eliminate the conventional problems to maintain the stable quality and the low unit consumption of raw materials, in the process for producing an acrylic ester using acrylic acid containing high-boiling acid components influencing the loss in quality and the unit consumption of raw materials, and an aliphatic or alicyclic alcohol having from 5 to 8 carbon atoms, as raw materials, and using a strongly acidic cation exchange resin as a catalyst. In such a process for producing an acrylic ester, a crude acrylic ester withdrawn from the bottom of a low-boiling separation column is supplied to a rectifying column, a rectified acrylic ester is taken out from the top of the rectifying column, while a high-boiling substance containing an acrylic ester, which is withdrawn from the bottom of the rectifying column, is supplied to a high-boiling separation column and/or a thin-film evaporator to separate it into an acrylic ester component and a high-boiling substance, and the separated acrylic ester component is taken out as a distillate and supplied to the low-boiling separation column for its recovery.
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Page/Page column 5-7
(2008/06/13)
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- Method For Making Alkyl (Meth) Acrylates by Direct Esterification
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The invention concerns a improved method for making linear, branched or cyclic C1-C15 alkyl(meth)acrylates, by direct esterification of (meth)acrylic acid with a corresponding alcohol, said reaction being catalyzed by sulfuric acid. The method includes a step of hydrolyzing the neutralizing aqueous flow followed by extraction of the residual (meth)acrylic acid with solvent consisting entirely or partly of the alcohol used in the reaction. The invention enables organic pollution (COD) released in the final aqueous effluents of the process to be reduced, as well as productivity to be increased.
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Page/Page column 4-5
(2008/12/07)
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- Method for refining easily polymerizable matter-containing substance and apparatus therefor
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A method for refining an easily polymerizable matter while preventing an easily polymerizable matter-containing substance from being polymerized and an apparatus for use in the method are disclosed. The method and apparatus for refining and separating the easily polymerizable matter-containing substance by the use of a distillation column provided with a heat exchanger set the linear velocity of a vapor in a connecting line intervening between the distillation column and the heat exchanger at a level of not less than 5 m per second and the retention time of the vapor at a level of not more than 3 seconds.
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Page/Page column 12-13
(2008/06/13)
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- Method for distilling (meth)acrylic acid and/or the ester thereof
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A method for distilling (meth)acrylic acid and/or the ester thereof by withdrawing vapor generated in a distillation column by distillation from the top of the column, condensing the vapor to give a condensate, and circulating part of the condensate as reflux liquid into the distillation column from the top thereof, comprising the step of adding a polymerization inhibitor to said condensate and said reflux liquid. This method enables maintaining the purity and quality of (meth)acrylic acid and/or the ester thereof at a certain level or higher, suppressing generation of polymers in the rectification column and suppressing polymerization of the condensate obtained by distillation in the incident facilities of the column such as condenser, condensate tank, and the like. In addition, the method enables reduction in the amount of polymerization inhibitor used while suppressing polymerization in the intermediate distillation columns (except the final rectification column).
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- Method for purifying (meth)acrylic acid
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A method for purifying a crude (meth)acrylic acid obtained by a vapor phase catalytic oxidation method, characterized in that the crude (meth)acrylic acid having most parts of water and acetic acid removed therefrom, is fed to and distilled in a first distillation column of a purification system comprising first to third three distillation columns, the top fraction from the first distillation column is fed to and distilled in the second distillation column, the resulting top fraction is recovered as a high purity (meth)acrylic acid product, the bottoms from the first and second distillation columns are fed to and distilled in the third distillation column, and the resulting top fraction is fed to the first distillation column.
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- COSMETIC POLYMER COMPOSITION AND COSMETIC
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The present invention discloses a cosmetic polymer composition containing a straight-chain block copolymer, where the copolymer having a unit derived from a compound having an ethylenic unsaturated bond, having a number-average molecular weight of 1.0×103 to 1.0×106, and having at least two or more glass transition points or melting points; a hair cosmetic polymer composition containing a copolymer a copolymer capable of forming a film having a Young's modulus of 50 MPa or larger and a fracture-point elongation of 100% or larger, and dispersible into water and/or alcohol; and a cosmetic material containing these compositions.
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- PROCESS FOR CONDUCTING EQUILIBRIUM-LIMITED REACTIONS
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This invention relates to a process for conducting equilibrium-limited reactions, such as esterification and alcoholysis reactions, that uses two reaction zones. The first reaction zone operates under reaction conditions that retain at least a portion of the product in a liquid phase, and at least a portion of the liquid from the first reaction zone is introduced into a second reaction zone which operates under conditions sufficient to crack heavies, for example, Michael-addition heavies, formed in or introduced into said second reaction zone and to vaporize at least a portion of the product upon production thereof. Such a process allows for removal of product from the reaction system while catalyst desirably remains in the reaction system.
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- Process for the conversion of aldehydes to esters
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A process for the conversion of aldehydes to esters, specifically acrolein or methacrolein to methyl acrylate or methyl methacrylate, respectively. Essentially in the absence of water, an aldehyde is contacted with an oxidizing agent to form an intermediate and then the intermediate is contacted with a diol or an alcohol to form an ester or diester. Preferably, the oxidizing agent is also a chlorinating agent. Specifically, acrolein or methacrolein is contacted with an oxidizing/chlorinating agent, such as t-butyl hypochlorite, and the chlorinated compound is contacted with an alcohol, such as methanol, to form methyl acrylate or methyl methacrylate, respectively. Generally, the order of addition is for the oxidizing agent to be added to the aldehyde, specifically for t-butyl hypochlorite to be added to acrolein or methacrolein, and for the diol or alcohol to be added to the intermediate, specifically for the methanol to be added to the reaction product of acrolein or methacrolein and t-butyl hypochlorite. The process of the present invention can be carried out in the absence or in the presence of solvent. Generally, better methyl acrylate or methyl methacrylate yields are obtained at lower reaction temperatures.
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Page/Page column 3-4
(2010/01/31)
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- Process for the production of alkyl (meth)acrylates by direct esterification
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An alkyl (meth)acrylate is prepared by a direct esterification (in 1) of (meth)acrylic acid by the corresponding alcohol, catalysed by H2 SO4. To the crude reaction mixture (C1) comprising the desired ester, alcohol, (meth)acrylic acid, alkyl hydrogen sulphate and traces of H2 SO4, there is added (in 3) a base to neutralize the acidic species, the resulting salts passing into the aqueous phase (A1), which is separated from the organic phase (O1) containing the desired ester. The light products (L1) containing the alcohol are recovered (in 4) from the aqueous phase, and the waste waters (W2) are expelled. A hydrolysis is carried out (in 8) of the alkyl hydrogen sulphate present in the aqueous phase (A1) obtained after the separation which is carried out after neutralization (in 3), to form the alcohol and H2 SO4 in this phase, the acidic species resulting from the hydrolysis are neutralized by introduction of a base .into the medium, and the resulting aqueous phase (A3) is directed to the step for recovery of the alcohol. Pollution of the waters (W2), attributable to the alkyl hydrogen sulphate, is thus avoided.
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- The 'Baylis - Hillman reaction' mechanism and applications revisited
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It is shown that reaction of aryl, benzyl, alkyl and functionalised alkyl acrylic esters with benzaldehyde, in the presence of 1,4-diazabicyclo[2.2.2] octane, strongly depends upon the electronic and steric effects of the ester part. This influence is also observed in condensation of furfuraldehyde. Moreover, for the first time, it is shown that the overall condensation is equilibrated.
- Fort, Yves,Berthe, Marie Christine,Caubere, Paul
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p. 6371 - 6384
(2007/10/02)
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- Use of n,n-dialkylhydroxylamines and their preparation
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The compounds of the formula (I) wherein R1 and R2 are independently alkyl of 8 to 36 carbon atoms, are useful for stabilizing a poly(arylene sulfide) resin, a modified poly-styrene or a polymer containing a diene component against thermal, oxidative or actinic degradation. N,N-Dialkylhydroxylamines of the formula (I) can be prepared by an improved process involving a reverse Michael reaction of the N-oxides of the corresponding β-dialkylaminopropionic esters, amides or nitriles or of β-dialkylaminosuccinyl esters or imides. N,N-Dialkylhydroxylamines of the formula (I) can also be prepared by an improved process involving the direct oxidation of the corresponding N,N-dialkylamines with aqueous hydrogen peroxide in a lower alkanol solvent.
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- Hydrophilic therapeutic material
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A hydrophilic therapeutic material comprising a carrier and a drug-containing patching layer formed thereon directly or indirectly, wherein said patching layer comprises a copolymer of 5 to 75% by weight of an acrylic or methacrylic ester having an ether group in the molecule, 85 to 15% by weight of an alkyl acrylate or alkyl methacrylate and 10 to 50% by weight of a polar monomer copolymerizable therewith.
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- Alkyl acrylate adducts of polyamines, ether amines and ether polyamines
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Disclosed are additives for hydrocarbon fuels which are the reaction products of a polyamine and an alkyl ester of acrylic or alkyl acrylic acid. A preferred composition is a mixture of the reaction product and oxygenated or non-oxygenated mono- or polyamines.
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