CS254237B1 - Method of 2-hydroxyethylmetacrylate cleaning - Google Patents
Method of 2-hydroxyethylmetacrylate cleaning Download PDFInfo
- Publication number
- CS254237B1 CS254237B1 CS862977A CS297786A CS254237B1 CS 254237 B1 CS254237 B1 CS 254237B1 CS 862977 A CS862977 A CS 862977A CS 297786 A CS297786 A CS 297786A CS 254237 B1 CS254237 B1 CS 254237B1
- Authority
- CS
- Czechoslovakia
- Prior art keywords
- hydroxyethyl methacrylate
- evaporator
- polymerization
- temperature
- freezer
- Prior art date
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- 238000000034 method Methods 0.000 title claims description 9
- 238000004140 cleaning Methods 0.000 title 1
- WOBHKFSMXKNTIM-UHFFFAOYSA-N Hydroxyethyl methacrylate Chemical compound CC(=C)C(=O)OCCO WOBHKFSMXKNTIM-UHFFFAOYSA-N 0.000 claims abstract description 22
- 238000006116 polymerization reaction Methods 0.000 claims abstract description 13
- 238000000746 purification Methods 0.000 claims abstract description 3
- 239000003381 stabilizer Substances 0.000 claims description 9
- 239000000178 monomer Substances 0.000 abstract description 8
- 229920000642 polymer Polymers 0.000 abstract description 4
- 239000007789 gas Substances 0.000 abstract description 3
- 239000002826 coolant Substances 0.000 abstract 1
- 239000002274 desiccant Substances 0.000 abstract 1
- 238000004519 manufacturing process Methods 0.000 abstract 1
- 230000000630 rising effect Effects 0.000 abstract 1
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 9
- 238000004821 distillation Methods 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N Hydroquinone Chemical compound OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 description 6
- 238000000354 decomposition reaction Methods 0.000 description 6
- 239000007788 liquid Substances 0.000 description 5
- CERQOIWHTDAKMF-UHFFFAOYSA-N Methacrylic acid Chemical compound CC(=C)C(O)=O CERQOIWHTDAKMF-UHFFFAOYSA-N 0.000 description 4
- VVQNEPGJFQJSBK-UHFFFAOYSA-N Methyl methacrylate Chemical group COC(=O)C(C)=C VVQNEPGJFQJSBK-UHFFFAOYSA-N 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- 238000009833 condensation Methods 0.000 description 3
- 230000005494 condensation Effects 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- AZQWKYJCGOJGHM-UHFFFAOYSA-N 1,4-benzoquinone Chemical compound O=C1C=CC(=O)C=C1 AZQWKYJCGOJGHM-UHFFFAOYSA-N 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000001879 gelation Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 238000005979 thermal decomposition reaction Methods 0.000 description 2
- CNHDIAIOKMXOLK-UHFFFAOYSA-N toluquinol Chemical compound CC1=CC(O)=CC=C1O CNHDIAIOKMXOLK-UHFFFAOYSA-N 0.000 description 2
- 238000005292 vacuum distillation Methods 0.000 description 2
- 125000000954 2-hydroxyethyl group Chemical group [H]C([*])([H])C([H])([H])O[H] 0.000 description 1
- OELQSSWXRGADDE-UHFFFAOYSA-N 2-methylprop-2-eneperoxoic acid Chemical class CC(=C)C(=O)OO OELQSSWXRGADDE-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-M Acrylate Chemical compound [O-]C(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-M 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- YCIMNLLNPGFGHC-UHFFFAOYSA-N catechol Chemical class OC1=CC=CC=C1O YCIMNLLNPGFGHC-UHFFFAOYSA-N 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000000994 depressogenic effect Effects 0.000 description 1
- 125000000118 dimethyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000004508 fractional distillation Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- NWVVVBRKAWDGAB-UHFFFAOYSA-N hydroquinone methyl ether Natural products COC1=CC=C(O)C=C1 NWVVVBRKAWDGAB-UHFFFAOYSA-N 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000005297 material degradation process Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000011403 purification operation Methods 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
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- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Čistenie monomeru 2-hydroxyetyImetakrylátu před jeho polymerizáeiou, při ktorom sa surový 2-hydroxyetylmetakryIát vyhřeje v stieranom filme s hrúbkou 0,1 až 1 mm v krátkocestnej odparke so vzdialenosteu odparovač —- chladíc 10 až 50 mm na teplotu 40 až 70 °G pri tlaku neskondenzovaternýeh plynov 1 až 100 Pa za čas 5'až 30 sekund a vzmkajúce páry kondenzují! v množstve 65 až 85 % z nástreku na chladiči odparky s teplotou —15 až +5 °C a v množstve· 5 až 20 % z nástreku vo vyrnrazovači za odparkou pri teplote —50 až —70 stupňov Celzia. Riešenie Je možné využit pri výrobě bioanalogických polymérov.Purification of 2-hydroxyethyl methacrylate monomer prior to its polymerization, wherein the crude 2-hydroxyethyl methacrylate is heated in a wiped film of 0.1 to 1 mm in a short-path evaporator with distance evaporator — 10 to 50 mm on temperature of 40 to 70 ° C under non-condenser pressure gases of from 1 to 100 Pa per time of 5 to 30 seconds and the rising steam condenses! in 65% to 85% of the coolant feed evaporators with a temperature of -15 to +5 ° C and v from about 5% to about 20% of the feed in the desiccant after the evaporator at -50 to -70 degrees Celsius. The solution can be used in the production of bioanalogic polymers.
Description
Vynález sa týká sposobu čistenia 2-hydroxyetylmetakrylátu před jeho polymerizáciou.The invention relates to a process for purifying 2-hydroxyethyl methacrylate prior to its polymerization.
Podlá doteraz známých postupov sa na čistenie hydroxyesterov kyseliny metakrylovej, ktoré sa po polymerizácii používajú ako· bioanalogické polyméry, využívá násadová vákuová destiilácia ipri teplotách 70 až 90 °C a tlakoch řádové 101 až 102 Pa, pričom vznikajúce páry sa zachytávajú v predloihe chladenej pevným CO2 na —60 °C. Pri tomto postupe často dochádza k čiastočnej alebo úplnej polymerizácii destilátu a tým k znehodnoteniu materiálu. Surový 2-hydroxyetylmetakrylát obsahuje ako nežiadúce příměsi vodu, etylénglykol, stabilizátor polymerizácie a podlá sposobu přípravy buď zbytky kyseliny metakrylovej alebo metylmetakrylátu.According to known methods, seed vacuum distillation is also used to purify the methacrylic acid hydroxy esters, which are used as bioanalogeneic polymers after polymerization, at temperatures of 70 to 90 ° C and pressures of the order of 10 1 to 10 2 Pa, the resulting vapors being collected in a pre-cooled solid CO2 to —60 ° C. This process often results in the partial or complete polymerization of the distillate and thus the material degradation. The crude 2-hydroxyethyl methacrylate contains as undesirable ingredients water, ethylene glycol, a polymerization stabilizer and, according to the method of preparation, either methacrylic acid or methyl methacrylate residues.
Voda, ktorej množstvo závisí od stupňa vysušenia reakčnej zmesi, je v zmesi viazaná vodíkovými mostíkmi, destiluje spolu s monomérom a je možné ju odstrániť iba frakčnou destiláciou v prednej frakcii. Opakované sušenie surového 2-hydroxyetylmetakrylátu je málo účinné a vedie k velkým stratám monomeru. Metylmetakrylát a kyselina metakrylová ako prchiavejšie zložky můžu byť odstránené v prednej frakcii.Water, the amount of which depends on the degree of drying of the reaction mixture, is bound in the mixture by hydrogen bridges, distills together with the monomer and can be removed only by fractional distillation in the front fraction. Repeated drying of the crude 2-hydroxyethyl methacrylate is poorly effective and leads to large monomer losses. Methyl methacrylate and methacrylic acid as more volatile components can be removed in the front fraction.
Vzhladom na to, že obidve tieto látky sú tiež polymerizácieschopné monomery, ich odstránenie zo zmesi je nevyhnutné, pretože pri polymerizácii 2-hydroxyetylmetakrylátu by sa zabudovávali do· vznikajúceho pólyměrného reťazca a nepriaznivo by ovplyvňovali jeho vlastnosti. Rovnako je potřebné odstrániť aj stabilizátor, brániaci samovořnej polymerizácii, ktorým obvykle bývá hydrochinón, metylhydrochinón, ich deriváty alebo deriváty pyrokatechinu.Since both of these substances are also polymerizable monomers, their removal from the mixture is necessary, since in the polymerization of 2-hydroxyethyl methacrylate they would be incorporated into the resulting polymeric chain and adversely affect its properties. It is also desirable to remove the stabilizer to prevent self-polymerization, which is typically hydroquinone, methyl hydroquinone, derivatives thereof or pyrocatechin derivatives.
Stabilizátor je v porovnaní s monomérom menej prchavý a ostávia v destilačnom zbytku. Nevýhodou násadovej vákuovej destilácie ako čistiacej operácie pre surový monomer je, že sa vykonává v násadě s dlhou dobou expozície destilovanej kvapaliny účinku vyšších teplot, pri ktorých dochádza k čiastočnému rozkladu tejto tepelne nestálej látky. Reakčné produkty z rozkladu sú vysoko reaktivně a spůsobujú polymerizáciu destilátu. Aj stabilizátor podlieha počas dlhodobého vyhrievania oxidácii a rozkladu a tieto prchavejšie produkty prechádzajú do destilátu a spůsobujú jeho nežiadúce zafarbenie.The stabilizer is less volatile compared to the monomer and remains in the distillation residue. The disadvantage of seed vacuum distillation as a purification operation for the crude monomer is that it is carried out in a batch with a long exposure time of the distilled liquid to the effects of higher temperatures at which this thermally unstable substance is partially decomposed. The reaction products from the decomposition are highly reactive and cause the polymerization of the distillate. Also, the stabilizer undergoes oxidation and decomposition during long-term heating, and these more volatile products pass into the distillate causing undesirable coloration.
Ďalšou nevýhodou násadovej destilácie je značná vzdialenosť medzi odparným a kondenzačným priestorom, v důsledku čoho sa v aparatúre ustaví určitý tlakový gradiént, čo znamená zvýšenú destilačnú teplotu a ďalšiu možnost tepelného rozkladu. Konečné nevýhodou je aj jediný kondenzátor pár, kde kondenzujú spoločne páry 2-hydroxyetylmetakrylátu s parami reaktívnych rozkladných produktov, vyvolávajúcich polymerizáciu.A further disadvantage of seed distillation is the considerable distance between the vaporization and condensation space, as a result of which a certain pressure gradient is established in the apparatus, which means an elevated distillation temperature and a further possibility of thermal decomposition. Finally, a single vapor condenser is also a drawback where 2-hydroxyethyl methacrylate vapors are condensed together with the vapor-reactive decomposition products causing polymerization.
Všetky tieto nevýhody sú odstránené pri spůsobe čistenia 2-hydroxyetylmetakrylátu před jeho· polymerizáciou podl'a vynálezu, podstatou ktorého je, že surový 2-hyďroxyetylmetakrylát sa vyhřeje v stieranom filme s hrúbkou 0,1 až 1 mm v krátkocestnej odparke so vzdialenosťou odparovač — chladič 10 až 50 mm na teplotu 40 až 70 °C pri tlaku neskondenzovatefných plynov 1 až 100 Pa za čas 5 až 30 s a vznikajúce páry kondenzujú v množstve 65 až 85 % z nástreku 11a chladiči odparky s teplotou —15 až +5 °C a v množstve 5 až 20 % z nástreku vo vymrazovači za odparkou pri teplote —50 až —70 °C.All these disadvantages are eliminated in the process of purification of 2-hydroxyethyl methacrylate prior to its polymerization according to the invention, which is based on the fact that the crude 2-hydroxyethyl methacrylate is heated in a 0.1 to 1 mm thick stripped film in a short path evaporator-cooler distance. 10 to 50 mm at a temperature of 40 to 70 ° C at a non-condensable gas pressure of 1 to 100 Pa over a period of 5 to 30, the vapors formed are condensed at 65-85% of the evaporator cooler feed at a temperature of -15 to +5 ° C and 5 to 20% of the feed in the freezer after evaporator at -50 to -70 ° C.
Postup čistenia surového· 2-hydroxyetylmetakrylátu podlá vynálezu má rad výhod. Je možné podlá nebo spolahlivo a pri dobrej výťažnosti získat čistý monomer, zbavený vody, cudzích monomérov a stabilizátora, s dobrou a reprodukovatefnou polymerizovatefnosťou a s požadovanými vlastnosťami polyméru. Vykonanie destilácie v krátkocestnej odparke v íenkom stieranom filme znamená jednak výrazné skrátenie doby vystavenia termolabilnej látky účinku zvýšených teplůt, jednak krátkocestné usporiadanie prakticky bez tlakových gradiéntov umožňuje využívat ešte nižšie pracovně teploty v porovnaní s klasickou vakuovou destiláciou.The process for purifying the crude 2-hydroxyethyl methacrylate according to the invention has a number of advantages. It is possible, depending on or reliably and at a good yield, to obtain pure monomer, free of water, foreign monomers and stabilizer, with good and reproducible polymerisability and with the desired polymer properties. Conducting distillation in a short-path evaporator in a light-wiped film means, on the one hand, a significant reduction in the exposure time of the thermolabile to elevated temperatures and, on the other hand, a short-path arrangement practically free of pressure gradients.
Obidva tieto faktory spolu s účinným premiešavaním kvapaliny vo· filme zabezpečujú minimálny tepelný rozklad destilovanej kvapaliny. Využívanie dvoch chladiacich ploch v zariadení dovoluje separátnu kondenzáciu pár 2-hydroxyetylmetakrylátu pri vyššej teplote a případných prchavých reaktívnych rozkladných produktov spolu s prchavějšími zložkami východiskovej zmesi pri nižšej teplote. Aj keď množstvo rozkladných produktov pri krátkocestnej filmovej destilácii 2-hydroxyetylmetakrylátu je minimálně, teplotně poměry na chladiči odparky sú záměrně vytvořené tak, že prchavejšie rozkladné zložky nie sú pri nich schopné kondenzácie a odchádzajú s vodou, etylénglykolom, metylmetakrylátom a kyselinou metakrylovou spolu s častou pár 2-hydroxyetylmetakrylátu do hlboko chladeného vymrazovača. Kondenzát z vymrazovača může byť s výhodou privádzaný do koncentrovanejšieho roztoku vhodného stahilizátora, čím sa zabrání gelatácii kondenzátu.Both these factors together with efficient mixing of the liquid in the film ensure minimal thermal decomposition of the distilled liquid. The use of two cooling surfaces in the apparatus allows separate condensation of the 2-hydroxyethyl methacrylate vapor at a higher temperature and any volatile reactive decomposition products together with the more volatile components of the starting mixture at a lower temperature. Although the amount of decomposition products in the short-path film distillation of 2-hydroxyethyl methacrylate is minimal, the evaporator cooler temperature conditions are deliberately designed such that the more volatile decomposition components are incapable of condensation and leave with water, ethylene glycol, methyl methacrylate and methacrylic acid. 2-hydroxyethyl methacrylate in a deep-chilled freezer. The condensate from the freezer may advantageously be fed into a more concentrated solution of a suitable depressant, thus avoiding gelation of the condensate.
Surový 2-hydroxyetylmetakrylát, obsahujúci vodu v množstve do 15 % hmot., etylénglykol, metylmetakrylát alebo kyselinu metakrylovú v množstve do 5 % hmot. a vhodný stabilizátor, například hydrochinon, v· množstve 0,001 až 0,5 % hmot., sa kontinuálně dávkuje na odparnú plochu krátkocestnej odparky so vzdialenosťou odparovač — kondenzátor 10 až 50 mm so stieraným filmom, pričom poměry stierania a velkost nástreku sú vhodné zvolené tak, aby hrúbka filmu sa pohybovala medzi 0,1 až 1 mm ia doba pobytu kvapaliny na odpař nejCrude 2-hydroxyethyl methacrylate containing up to 15% by weight of water, ethylene glycol, methyl methacrylate or methacrylic acid up to 5% by weight and a suitable stabilizer, for example hydroquinone, in an amount of 0.001 to 0.5% by weight, is continuously metered onto the evaporation surface of a short-path evaporator with a 10 to 50 mm wiped film condenser distance, with wiping ratios and feed rates suitable to a film thickness of between 0.1 and 1 mm and the residence time of the liquid on the evaporator
4 5 ploché 5 až 30 s. Kvapalina vo filme sa vyhřeje na teplotu 40 až 70 °C pri tlaku neskondenzo-vatelných plynov 1 až 100 Pa.4 5 flat 5 to 30 s. The liquid in the film is heated to a temperature of 40 to 70 ° C at a non-condensable gas pressure of 1 to 100 Pa.
Vznikajúce páry kondenzuji! na chladiči odparky, v ktorom sa pomocou termostatu udržuje teplota —15 až -|-5 °C tak, -aby sa získal kondenzát čistého 2-hydroxyetylmetakrylátu v množstve 65 až 85 % z nástreku. Časf pár v množstve 5 až 20 % z nástreku odchádza do vymrazovača za odparkou, ktorý je hlboko chladený na teplotu —50 až —70 °C, například pevným CO2. V zbernej nádobě kondenzátu z vymrazovača može byt roztok vhodného stabilizátora s koncentráciou 0,1 až 0,5 % hmot., takže prchavé reaktivně látky nevyvolají! gelatáciu kondenzátu.Condensed vapors condense! on a evaporator cooler in which a thermostat is maintained at a temperature of -15 to -5 ° C so as to obtain a condensate of pure 2-hydroxyethyl methacrylate in an amount of 65 to 85% of the feed. A portion of the vapors in an amount of 5 to 20% of the feed goes to the freezer downstream of the evaporator, which is deeply cooled to a temperature of -50 to -70 ° C, for example with solid CO 2. In the condensate collector from the freezer, there can be a solution of a suitable stabilizer with a concentration of 0.1 to 0.5% by weight, so that volatile reactive substances do not evoke! condensate gelation.
Příklad 1Example 1
Surový 2-hyd-roxyetylmetakrylát, obsahujúci 8,5 % hmot. vody, 0,05 % hmot. hycirochinónu ako stabilizátora, sa v krátkecestnsj odparke so- stieraným filmom soCrude 2-hydroxyethyl methacrylate containing 8.5 wt. % water, 0.05 wt. % of the hydrotinone quinone stabilizer, in a short-lived evaporator, the coated film was removed
7 vzdialeno-sťou odparovač — chladič 15 mm pri hrúbke filmu 0,1 mm pri strednej době pobytu 12 s vy-hrial na teplotu 60 CC pri tlaku 3 až 5 Pa. Pri teplote chladiča 0 °C sa získal destilát v množstve 77 % z nástreku a vo vymrazovači pri teplote —65 °C bol zachytený kondenzát v množstve 7 % z nástreku. Destilačný zbytok bol asi 15 % z nástreku. Čistý 2-hydroxyetylimet-akrylát, získaný ako destilát z odparky, mal obsah vody 0,1 % hmot., dalšie zložky v ňom neboli zistené. Kondenzát z vymrazovača vykazoval gélovitú konzistenciu.7 with a vaporizer-condenser distance of 15 mm at a film thickness of 0.1 mm at a mean residence time of 12 s heated to 60 DEG C. at a pressure of 3 to 5 Pa. At a cooler temperature of 0 ° C, 77% of the feed was recovered and 7% of the feed condensate was collected in the freezer at -65 ° C. The distillation residue was about 15% of the feed. Pure 2-hydroxyethyl dimethyl acrylate, obtained as the distillate from the evaporator, had a water content of 0.1% by weight, no other components were detected. The condensate from the freezer showed a gel-like consistency.
Příklad 2Example 2
Surový 2-hydroxyetylmetakrylát bol spracovaný analogicky ako v příklade 1 s tým, že do zbernej nádoby vymrazovača sa ešte před destiláciou vložilo asi 5 ml roztoku hydrochinónu v 2-hydroxyetylmetakryláte s koncentráciou 0,2 % hmot. V kondenzáte z vymrazovača po destilácii nedošlo k polymerizácii.The crude 2-hydroxyethyl methacrylate was treated analogously to Example 1 except that about 5 ml of a 0.2% by weight solution of hydroquinone in 2-hydroxyethyl methacrylate was added to the freezer collector prior to distillation. There was no polymerization in the condensate from the freezer after distillation.
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CS862977A CS254237B1 (en) | 1986-04-24 | 1986-04-24 | Method of 2-hydroxyethylmetacrylate cleaning |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CS862977A CS254237B1 (en) | 1986-04-24 | 1986-04-24 | Method of 2-hydroxyethylmetacrylate cleaning |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CS297786A1 CS297786A1 (en) | 1987-05-14 |
| CS254237B1 true CS254237B1 (en) | 1988-01-15 |
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ID=5368525
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CS862977A CS254237B1 (en) | 1986-04-24 | 1986-04-24 | Method of 2-hydroxyethylmetacrylate cleaning |
Country Status (1)
| Country | Link |
|---|---|
| CS (1) | CS254237B1 (en) |
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1986
- 1986-04-24 CS CS862977A patent/CS254237B1/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| CS297786A1 (en) | 1987-05-14 |
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