- Runge-Kutta analysis for optimizing the Zn-catalyzed transesterification conditions of MA and MMA with diols to maximize monoesterified products
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Terminal hydroxylated acrylates and methacrylates were prepared by catalytic transesterification of acrylates and methacrylates with diols catalyzed by a system of a tetranuclear zinc alkoxide, [Zn(tmhd)(OMe)(MeOH)]4 (1a), with 4 equiv. of 2,2′-bipyridine (L1). The reaction time to reach the equilibrium state was analyzed by kinetic studies and a curve-fitting analysis based on the Runge-Kutta method for optimizing the best reaction conditions for mono-esterification. In addition to these kinetic analyses, DFT calculations estimated a proposed mechanism of the catalytic transesterification. This journal is
- Akebi, Shin-Ya,Kato, Taito,Mashima, Kazushi,Nagae, Haruki,Oku, Tomoharu,Yonehara, Koji
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p. 6975 - 6986
(2021/11/17)
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- Synthesis method of 1,4-butylene glycol dimethacrylate
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The invention discloses a synthesis method of 1,4-butylene glycol dimethacrylate, and belongs to the field of organic chemical industry. The synthesis method includes the steps that when reaction rawmaterials: 1,4-butanediol, methacrylic acid, a polymerization inhibitor and a water-carrying agent are heated to 80-90 DEG C, an HZSM-5 molecule sieve is added to serve as a catalyst, the temperatureis increased and kept to be 100-130 DEG C, the 1,4-butanediol and the methacrylic acid are subjected to an esterification reaction to generate 1,4-butylene glycol dimethyl alkenyl benzoate; after thereaction is completed, cooling is conducted to the room temperature, the catalyst is filtered and separated, still standing for layering is conducted in a separating funnel, and an upper layer organicphase is taken; the organic phase is washed with distilled water for 2-3 times; and then vacuum distillation is conducted to remove an organic solvent, and after cooling, a target product, namely the1,4-butylene glycol dimethacrylate is obtained. The catalyst has high activity, good selectivity, the mild reaction condition, easy and convenient post-treatment and no corrosivity, and is easy to separate and capable of being reused, and thus the synthesis method is high in production safety, low in energy consumption and high in yield.
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Paragraph 0012-0016
(2020/01/25)
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- 1,4-butanediol dimethylacrylate preparation method
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The invention provides a 1,4-butanediol dimethylacrylate preparation method. Under the action of a solid catalyst acid sodium bisulphate, in the presence of a polymerization inhibitor and an azeotropic water-carrying agent, 1,4-butanediol and methacrylic acid are reacted at 80 to 90 DEG C for 4 to 7 hours for synthesis to obtain 1 , 4-butanediol dimethacrylate; the molar ratio of methacrylic acidto 1,4-butanediol is 2.10:1, and the amount of n-hexane in the azeotropic water-carrying agent accounts for 50% of the total mass of a reactant, the solid acid catalyst accounts for 3% of the total mass of the reactant, and the amount of the polymerization inhibitor phenothiazine accounts for 0.05% of the total mass of the reactant. the catalyst used in the synthesis method of 1,4-butanediol dimethacrylate is cheap, stable, easy to separate from products, and does not corrode equipment, the 1,4-butanediol dimethacrylate achieves the purpose of clean production, has high yield, and has broad application prospects.
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Paragraph 0013-0034
(2019/01/08)
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- Synthesis method of 1,4-butanediol dimethyl acrylic ester
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The invention relates to the field of rubber synthesis and discloses a synthesis method of 1,4-butanediol dimethyl acrylic ester. Methacrylic acid and 1,4-butanediol are used as raw materials, dicyclohexylcarbodiimide is used as a dehydrating agent, a reaction is conducted at -5-0 DEG C, and then through filtration, concentration and rectification, 1,4-butanediol dimethyl acrylic ester is prepared. According to the synthesis method, the adopted raw material is wide in source and low in price, the reaction temperature is low, poisonous gas is not generated in the reaction process, aftertreatment is simple, and the obtained product is high in yield and purity.
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Paragraph 0022-0027
(2018/10/11)
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- METHOD FOR THE PRODUCTION OF (METH)ACRYLIC ESTERS
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The present invention relates to a process for preparing (meth)acrylates, comprising the transesterification of a low-boiling ester of (meth)acrylic acid with a reactant alcohol in the presence of catalysts, which is characterized in that the transesterification is catalysed by a basic ion exchanger.
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Page/Page column 5
(2011/06/23)
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- METHOD FOR PRODUCING BUTANEDIOL DIMETHACRYLATES
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The present invention relates to a process for preparing butanediol dimethacrylates, which comprises the transesterification of butanediol with an ester of methacrylic acid in the presence of catalysts, wherein a combination comprising at least one lithium compound and at least one calcium compound is used as catalyst, at least one of the compounds of lithium and/or of calcium is an oxide, a hydroxide, an alkoxide having from 1 to 4 carbon atoms or a carboxylate having from 1 to 4 carbon atoms and at least part of the reaction is carried out in the presence of an effective amount of water. The process of the invention makes a particularly inexpensive preparation of butanediol dimethacrylates having a very high purity possible.
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Page/Page column 4
(2010/08/08)
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- Photocurable Perfluoropolyethers for Use as Novel Materials in Microfluidic Devices
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A functionalized photocurable perfluoropolyether is used as a material for fabricating a solvent-resistant microfluidic device. Such solvent resistant microfluidic devices can be used to control the flow of small amounts of a fluid, such as an organic solvent, and to perform microscale chemical reactions that are not amenable to other polymer-based microfluidic devices.
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- Bulky monomers leading to resins exhibiting low polymerization shrinkage
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The invention relates to a dental composite material wherein space-filling compounds are utilized to reduce shrinkage upon polymerization; the invention also relates to a method for producing dental restoration articles with reduced shrinkage; the invention also relates to various dental restorative articles comprising the aforementioned space-filling compounds.
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- Process for synthesis of Di(meth)acrylic acid esters
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A process for the synthesis and recovery of di(meth)acrylic acid esters at a high degree of purity. Di(meth)acrylic acid esters are produced by transesterfication of (meth)acrylic acid esters of C1to C4alcohols with 1,n-diols (where n≧3) in the presence of a zirconium catalyst that comprises a chelate of zirconium with a 1,3-dicarbonyl compound. These catalysts can be readily separated or removed from the reaction mixture by precipitation with phosphoric acid, thus providing a convenient and inexpensive method of producing a di(meth)acrylic acid ester with a reduced level of zirconium.
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Page/Page column 6
(2008/06/13)
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- Raman Scattering Study of Butane-1,4-diol Dimethacrylate
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A study of the Raman light scattering in butane-1,4-diol dimethacrylate was performed in the temperature range 12-37 deg C.It was found that the temperature dependence of the relative intensities of the bands deriving from the C=C, C=O and =C-H bonds reveals a discontinuity at ca. 21-24 deg C which coincides with the previously observed temperature discontinuity of the optical Kerr effect and Brillouin light scattering.The result is discussed in terms of changes in molecular interactions and arrangement in the liquid compound investigated.
- Andrzejewska, Ewa,Blaszczak, Zdzislaw,Drozdowski, Miroslaw,Kasprowicz, Dobroslawa,Kozielski, Marek
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p. 2339 - 2342
(2007/10/02)
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- 4,4'-(perfluoroisopropylidene)dicyclohexanol, derivative thereof and process for preparing the same
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4,4'-(Perfluoroisopropylidene)dicyclohexanol or its organic acid ester of the formula STR1 wherein R' is hydrogen atom or acyl group having 1 to 10 carbon atoms, is useful as a starting material of a curable resin, cross-linking agent or the like.
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- Unsaturated esters of adamantane containing diols and thermo-resistant cross-linked polymers therefrom
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Diacrylate and dimethacrylate esters corresponding to the formula STR1 wherein R and R' are hydrogen or methyl and A is either a sigma (?) bond; a (CH2)η radical where η is an interger that may vary from one through four; or phenylene, or an alkyl derivative thereof. The new adamantane containing difunctional olefinic monomers can then be polymerized, or copolymerized with other acrylic type olefinic monomers to produce polymers with unusual physical properties, including unusual hardness, inertness to degradable agents, and resistance to heat.
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- Dimethacrylic acid esters of dimethyloltetrahydrofuran and its derivatives
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The present invention relates to dimethacrylic acid esters of dimethyloltetrahydrofuran and its derivatives having the formula: STR1 wherein A and A' individually have the formula: STR2 wherein B is a member selected from the group consisting of CH3 and H, n is an integer from 0 to 5, m is 0 or 1, and p is 0 or 1; their process of preparation and their use as adhesive components of anaerobic adhesive compositions.
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- Hydroxy group containing diesters of acrylic acid
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Polymerizable hydroxy-group-containing diesters of acrylic acids for dental material are prepared by reacting 3-(3,4-epoxycyclohexyl)-8,9-epoxy-2,4-dioxaspiro(5,5) undecane or a bis-epoxide of formula (A) STR1 or a bis-epoxide of formula (B) STR2 with a hydroxyalkylacrylate or hydroxyalkylmethacrylate containing 2 to 10 carbon atoms in the alkyl portion, n being 0 or 1 in formula (A) with the proviso that when n is 0, X is --0-- and R1 is --H; and when n is 1, X is selected from the group of alkylene with 1 to 10 carbon atoms, C1-3 -alkyl substituted alkylene with 1 to 10 carbon atoms, --O--(CH2)m --O-- where m is 1 to 10, --CH2 --OCO--(CH2)p --COO--CH2 where p is 1 to 6, and --CH2 --OCO--, and R1 is --H or --CH3, and in formula (B) STR3 or tricyclo-[5.2.1.02,6 ]-decylene.
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- New Rf -glycols containing two perfluoroalkylthio groups and useful compositions therefrom
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Perfluoroalkylthio glycols and esters thereof can be prepared by the free-radical catalyzed addition of a perfluoroalkylthiol to an acetylenic alcohol or ester thereof. The compounds obtained are useful intermediates for the synthesis of fluorochemicals with low free surface energies having oil and water repellent properties. In one embodiment, a perfluoroalkylthio glycol can be reacted with a diisocyanate to obtain a polyurethane containing perfluoroalkylthio groups, which polyurethanes are useful as coatings to provide oil and water repellence to textiles and as additives to plastics to provide mold-release and other desirable properties.
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