872-36-6Relevant articles and documents
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Johnson,Patton
, p. 1042 (1960)
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Method for producing a vinylene carbonate
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Paragraph 0032; 0035-0037, (2021/11/02)
[Problem] to a dehydrochlorination reaction of tertiary amine [monokuroroechirenkaboneto[monokuroroechirenkaboneto], high yield production of coloring of the vinylene carbonate is suppressed. [Solution] using the tertiary amine [monokuroroechirenkaboneto[monokuroroechirenkaboneto] dehydrochlorination reaction, performed in the first reaction solution obtained in the first step of the first solvent, the second solvent can be added to the first reaction to a second reaction in the second step, the reaction solvent was removed from the first second third reaction in the second step, the fourth step may be removed from the reaction solution-third fourth reaction, a fourth method for producing a vinylene carbonate from the reaction liquid, the third liquid and fourth liquid reaction mixture obtained was washed with a solvent for the solid mixture liquid from the fourth method for producing a vinylene, a fourth step of solvent washing liquid obtained from the first solid-liquid mixed solvent was removed from the reaction solution with a fourth manufacturing method for obtaining a fourth bottom vinylene, further, a fourth step of solvent washing liquid obtained by washing the solid second reaction liquid mix of the fifth manufacturing method is solved by a vinylene carbonate. [Drawing] no
Synthesis method of vinylene carbonate
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Paragraph 0017; 0019-0022, (2019/12/02)
The invention discloses a synthesis method of vinylene carbonate, which comprises the following steps: by using chlorine and ethylene carbonate as reaction raw materials and carbon tetrachloride as amedium, synthesizing monochloroethylene carbonate at 70 DEG C under the illumination of an LED blue light lamp; after the reaction is finished, evaporating out the carbon tetrachloride, and carrying out reduced pressure distillation to obtain the monochloroethylene carbonate; mixing the monochloroethylene carbonate obtained with methyl tert-butyl ether according to a certain ratio; dropwise addingtriethylamine at 55-58 DEG C under the condition of taking 2,2,6,6-tetramethyl-4-hydroxypiperidine nitroxide free radicals as a polymerization inhibitor; reacting the mixture at 60-62 DEG C after addition is finished; and after the reaction is finished, carrying out suction filtration, washing, and evaporation to obtain the triethylamine and the methyl tert-butyl ether; and carrying out reduced pressure distillation to obtain the vinylene carbonate. According to the improvement of the synthesis method, the raw materials are simple and easy to obtain, the process is simple, less waste is generated, and the total yield can reach 58% or above; the method is suitable for large-scale industrial production.
POLYVINYL ALCOHOL PARTICLES, PHARMACEUTICAL BINDER USING SAME, PHARMACEUTICAL TABLET, SUSTAINED-RELEASE PHARMACEUTICAL TABLET, AND METHOD FOR PRODUCING POLYVINYL ALCOHOL PARTICLES
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, (2017/08/22)
Provided herein is a polyvinyl alcohol fine particle suitable for a pharmaceutical binder for obtaining a pharmaceutical tablet of properties including good sustained release, high hardness, and excellent friability. The polyvinyl alcohol tine particle of the present invention contains 25 mol % or more of a gauche structure in polyvinyl alcohol molecules within a 0.8-nm region inside the particle from the particle surface.