- Preparation of acrylic acid addition polymer and application of acidic catalyst in preparation of acrylic acid addition polymer
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The invention relates to preparation of an acrylic acid addition polymer and application of an acidic catalyst in preparation of the acrylic acid addition polymer. According to the application of theacidic catalyst in preparation of the acrylic acid addition polymer, the acidic catalyst is one or more of protonic acid, Lewis acid and solid acid. The inventor of the invention finds that the acidiccatalyst of protonic acid, Lewis acid or solid acid can be used for catalyzing a Michael addition reaction of acrylic acid to prepare the acrylic acid addition polymer with good catalytic activity. In addition, the method for preparing the acrylic acid addition polymer through acrylic acid addition polymerization is simple in reaction process operation, convenient in process step control and highin addition polymerization yield.
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Paragraph 0043-0045; 0046-0053
(2019/07/01)
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- Method for lowering acrylic acid dimer in acrylic acid
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The invention discloses a method for lowering acrylic acid dimer in acrylic acid.The method comprises the steps that industrial acrylic acid is used as a raw material, the acrylic acid is placed in an ultrasonic generator, circulation cooling water is introduced, the ultrasonic generator is turned on, the ultrasonic wave power and frequency are adjusted, the ultrasonic treatment time is set, and ultrasonic treatment starts to be carried out.The content of the acrylic acid dimer is obviously lowered through high performance liquid chromatography detection.Depolymerization of the acrylic acid dimmer is promoted through the ultrasonic cavitation effect, the mechanical vibration effect and the heat effect.The content of the acrylic acid dimmer is lowered from 10-20% to 1% or below after treatment.The acrylic acid treated through the method is used as the raw material for producing a down-stream product such as thiodiglycolic acid, and the content of acrylic acid dimer in the product is obviously lowered.According to the method, operation is easy, the effect is obvious, safety is good, the cost is low, and industrial application is easy to achieve.
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Paragraph 0044; 0045
(2017/01/05)
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- RENEWABLE ACRYLIC ACID PRODUCTION AND PRODUCTS MADE THEREFROM
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Processes and methods for making biobased acrylic acid products including acrylic acid, acrylic acid oligomers, acrylic acid esters, acrylic acid polymers and articles from renewable carbon resources are described herein.
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Paragraph 00113
(2014/01/08)
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- Coatings for medical articles including natural biodegradable polysaccharides
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Biodegradable coatings that include natural biodegradable polysaccharides are described. The coating is formed from a plurality of natural biodegradable polysaccharides having pendent coupling groups.
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- Synthesis, determination of absolute configuration, and biological evaluation of spiro-fused thiadiazoline inhibitors of kinesin spindle protein (KSP)
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A facile and highly convergent synthesis of biologically active spiro-fused thiadiazoline KSP inhibitors is reported. The highlights of the synthesis include the Michael reaction and cyclization of thiosemicarbazone to 1,3,4-thiadiazoline. This chemistry lends itself to the preparation of (+)-2, a potent and orally bioavailable anti-cancer agent, and to the development of a structure-activity relationship program.
- Angeles, Angie R.,Yang, Liping,Dai, Chaoyang,Brunskill, Andrew,Basso, Andrea D.,Siddiqui, M. Arshad
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supporting information; experimental part
p. 6236 - 6239
(2011/01/12)
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- PROCESS FOR PREPARING ACRYLIC ACID
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A process for preparing acrylic acid, in which an acrylic acid-comprising product gas mixture obtained by catalytic gas phase partial oxidation of a C3 precursor of acrylic acid is fractionally condensed in a condensation column provided with internals ascending into itself with side draw removal of crude acrylic acid and with liquid phase draw removal of acrylic acid-comprising acid water, and acrylic acid present in acid water is taken up into an extractant and then removed from the extractant and recycled into the condensation column, or taken up in aqueous metal hydroxide, or sent to further purification of the crude acrylic acid.
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Page/Page column 16
(2008/12/07)
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- BIODEGRADABLE OCULAR IMPLANTS AND METHODS FOR TREATING OCULAR CONDITIONS
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Biodegradable ocular implants are described. The ocular implants include a bioactive agent that can be released within the eye to treat an ocular condition or indication. The implants can be used for the administration of a bioactive agent over prolonged periods of time. In some aspects the implants are formed of a matrix of natural biodegradable polysaccharides.
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Page/Page column 48
(2008/12/05)
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- Biodegradable ocular implants and methods for treating ocular conditions
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Biodegradable ocular implants are described. The ocular implants include a bioactive agent that can be released within the eye to treat an ocular condition or indication. The implants can be used for the administration of a bioactive agent over prolonged periods of time. In some aspects the implants are formed of a matrix of natural biodegradable polysaccharides.
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- Coatings including natural biodegradable polysaccharides and uses thereof
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Biodegradable coatings and articles that include natural biodegradable polysaccharides are described. The coatings and articles are formed from a plurality of natural biodegradable polysaccharides having pendent coupling groups.
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- Method for inhibiting polymerization of (meth)acrylic acid and its esters using an inhibitor and a process for making a compound useful as such an inhibitor
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This invention relates to a method for inhibiting polymerization of (meth)acrylic acid and its esters using a polymerization inhibitor which comprises at least one reduced halide-content azine dye-based compound. A process for producing reduced halide-content azine dye-based compounds using ion exchange resin technology is also provided.
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Page/Page column 11
(2010/10/20)
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- CLEAVING OLIGOMERIC (METH)ACRYLIC ACID IN THE LIQUID PHASE AND UNDER PRESSURE
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The invention relates to a method for cleaving a (meth)acrylic acid oligomer of structure (I), optionally in the presence of a cleaving agent of structure R3-OH or of structure (R4)2-N-H. The (meth)acrylic acid oligomer, together with the cleaving agent, is heated to a temperature of at least 50 °C and under a pressure of at least 1 bar. The invention also relates to the use of water, optionally with a protic compound serving as a cleaving agent, for cleaving (meth)acrylic acid oligomers, to a device for synthesizing (meth)acrylic acid, to the use of this device for producing (meth)acrylic acid, and to the (meth)acrylic acid produced while using said device.
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Page/Page column 24-25; 27; 36; sheet 1/3-3/3
(2010/02/13)
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- Macrocyclic Oligolactones by Oligomerization of Simple Lactones
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The catalyst system K-t-butoxide/THF is useful not only for converting ε-caprolactone into the known cyclic oligomers (14-, 21-, 28-ring etc.) but also for preparing the unknown cyclic oligomers of δ-valerolactone (12-, 18-, 24-ring etc.) if large amounts of catalyst are used in the presence of t-butyl alcohol.With γ-butyrolactone, the acidity of the α-CH2 leads instead to a bicyclic aldol type condensation product for which there is evidence of subsequent dimerization to a tricyclic 10-ring dilactone. β-Propiolactone undergoes eliminative ring-opening to acrylic acid which is in equilibrium with acyclic homologues.In contrast, the catalyst system BF3/CH2Cl2 converts β-propiolactone (but not the other lactones) cleanly to cyclic oligomers (12-, 16-, 20-ring etc.).The driving force for these reactions is primarily the instability of the cis ester configuration in monolactones, the ester groups of the oligolactones adopting exclusively the trans ester configuration.Ring strain seems to contribute only in the case of β-propiolactone.
- Dale, Johannes,Schwartz, Jan-Erik
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p. 559 - 567
(2007/10/02)
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