Hydroxypropyl Methyl Cellulose Ether Ikoranabuhanga

Hydroxypropyl methyl selulose ether ni ubwoko bwa selulose etulée ether solubose mumazi akonje yakuwe muri selile naturel binyuze muri alkalisation no guhindura etherification.

Ijambo ryibanze:hydroxypropyl methylcellulose ether; alkalisation reaction; etherification reaction

1. Ikoranabuhanga

Cellulose karemano ntishobora gushonga mumazi no mumashanyarazi, bihamye kumucyo, ubushyuhe, aside, umunyu nibindi bitangazamakuru byimiti, kandi birashobora guhindurwamo umuti wa alkali yumuti kugirango uhindure ubuso bwa selile.

Hydroxypropyl methyl selulose ether ni ubwoko bwa non-polar, amazi akonje ya selile yamashanyarazi yabonetse muri selile naturel binyuze muri alkalisation no guhindura etherification.

2. Inzira nyamukuru yimiti

2.1 Alkalisation reaction

Hariho uburyo bubiri bushoboka bwo gukora reaction ya selile na sodium hydroxide, ni ukuvuga, ukurikije ibihe bitandukanye kugirango habeho ibice bya molekile, R - OH - NaOH; cyangwa kubyara ibyuma byinzoga, R - ONa.

Intiti nyinshi zemeza ko selile yifata hamwe na alkali yibanze kugirango ibe ikintu gihamye, kandi batekereza ko buri tsinda rya glucose cyangwa bibiri byahujwe na molekile imwe ya NaOH (itsinda rimwe rya glucose rihujwe na molekile eshatu za NaOH iyo reaction irangiye).

C6H10O5 + NaOH→C6H10O5 NaOH cyangwa C6H10O5 + NaOH→C6H10O4 ONa + H2O

C6H10O5 + NaOH→(C6H10O5) 2 NaOH cyangwa C6H10O5 + NaOH→C6H10O5 C6H10O4 ONa + H2O

Vuba aha, intiti zimwe zemeza ko imikoranire hagati ya selile na alkali yibanze izagira ingaruka ebyiri icyarimwe.

Hatitawe ku miterere, ibikorwa bya chimique ya selile birashobora guhinduka nyuma yibikorwa bya selile na alkali, kandi irashobora kubyitwaramo nibitangazamakuru bitandukanye byimiti kugirango ibone amoko afite akamaro.

2.2

Nyuma ya alkalisation, selile ya alkali selile ikora hamwe na etherification agent kugirango ikore selile. Ibikoresho bya etherifingi bikoreshwa ni methyl chloride na okiside ya propylene.

Sodium hydroxide ikora nka catalizator.

n na m byerekana urwego rwo gusimbuza hydroxypropyl na methyl kuri selile ya selile. Umubare ntarengwa wa m + n ni 3.

Usibye ibisubizo byavuzwe haruguru byavuzwe haruguru, hari n'ibisubizo kuruhande:

CH2CH2OCH3 + H2O→HOCH2CH2OHCH3

CH3Cl + NaOH→CH3OH + NaCl

3. Ibisobanuro byerekana hydroxypropyl methylcellulose ether

Inzira ya hydroxypropyl methyl selulose ether (“selulose ether” muri make) igizwe nibintu 6, aribyo: kumenagura ibikoresho fatizo, (alkalinisation) etherification, kuvanaho umusemburo, kuyungurura no kumisha, kumenagura no kuvanga, no gupakira ibicuruzwa byarangiye.

3.1 Gutegura ibikoresho

Cellulose isanzwe ngufi yaguzwe ku isoko ijanjagurwa ifu na pulverizer kugirango byoroherezwe gutunganywa nyuma; alkali ikomeye (cyangwa alkali y'amazi) irashonga igategurwa, igashyuha kugeza kuri 90°C gukora 50% caustic soda igisubizo cyo gukoresha. Tegura reaction ya methyl chloride, propylene oxyde etherification agent, isopropanol na toluene reaction solvent icyarimwe.

Byongeye kandi, uburyo bwo kubyitwaramo busaba ibikoresho byingirakamaro nkamazi ashyushye namazi meza; amazi, amazi akonje yo hasi, hamwe namazi akonje asabwa kugirango afashe ingufu.

Imirongo migufi, methyl chloride, na propylene oxyde etherification nibikoresho byingenzi byo gukora selile ya etherifile, kandi imirongo migufi ikoreshwa mubwinshi. Methyl chloride na propylene oxyde igira uruhare mubitekerezo nka etherification agent kugirango ihindure selile karemano, ubwinshi bwikoreshwa ntabwo ari bunini.

Umuti (cyangwa diluents) ushiramo ahanini toluene na isopropanol, ahanini ntibikoreshwa, ariko urebye igihombo cyashizwemo kandi gihindagurika, habaho igihombo gito mumusaruro, kandi amafaranga yakoreshejwe ni make cyane.

Gahunda yo gutegura ibikoresho bibisi ifite ikigega kibisi hamwe nububiko bwibikoresho bifatika. Ibikoresho bya Etherifying hamwe na solge, nka toluene, isopropanol, na acide acike (bikoreshwa muguhindura pH agaciro ka reaction), bibikwa mukibanza cyibikoresho fatizo. Itangwa rya lint ngufi irahagije, irashobora gutangwa nisoko igihe icyo aricyo cyose.

Intoki ngufi zajanjaguwe zoherezwa mu mahugurwa hamwe n'ikarita yo gukoresha.

3.2 (Alkalinisation) etherification

(Alkaline) etherification ninzira yingenzi mugikorwa cya etherification ya selile. Muburyo bwo kubyaza umusaruro mbere, intambwe ebyiri reaction zakozwe zitandukanye. Noneho inzira iratera imbere, kandi ibyiciro byintambwe ebyiri byahujwe murwego rumwe kandi bigakorerwa icyarimwe.

Banza, vuga ikigega cya etherification kugirango ukureho umwuka, hanyuma usimbuze azote kugirango ikigega kitagira umwuka. Ongeramo igisubizo cya sodium hydroxide yateguwe, ongeramo umubare munini wa isopropanol na soluène ya toluene, tangira gukurura, hanyuma ushyiremo ubwoya buto buto, fungura amazi azenguruka kugirango ukonje, hanyuma ubushyuhe bumaze kugabanuka kurwego runaka, fungura hasi- ubushyuhe bwamazi kugirango ugabanye sisitemu ubushyuhe bwibintu Kugabanuka kugera kuri 20℃, kandi ukomeze reaction mugihe runaka kugirango urangize alkalisation.

Nyuma ya alkalisation, ongeramo agent ya methyl chloride na okiside ya propylene yapimwe na tanki yo murwego rwohejuru, komeza utangire kubyutsa, koresha amavuta kugirango ubushyuhe bwa sisitemu bugere kuri 70℃~ 80℃, hanyuma ukoreshe amazi ashyushye kugirango ukomeze gushyushya no kubungabunga Ubushyuhe bwa reaction buragenzurwa, hanyuma ubushyuhe bwa reaction nigihe cyo kubyitwaramo bikagenzurwa, kandi igikorwa gishobora kurangizwa no gukurura no kuvanga mugihe runaka.

Igisubizo gikorerwa nka 90°C na 0.3 MPa.

3.3 Kurimbuka

Ibikoresho byavuzwe haruguru byavuzwe haruguru byoherezwa muri desolventizer, hanyuma ibikoresho biramburwa kandi bishyushya hamwe na parike, kandi umusemburo wa toluene na isopropanol uhumeka hanyuma ugasubirwamo kugirango ukoreshwe.

Umuyaga uhumeka ubanza gukonjeshwa hanyuma ugahuzwa igice hamwe namazi azenguruka, hanyuma ugahuzwa namazi yubushyuhe buke, hanyuma imvange ya kondensate yinjira mukibanza cyamazi no gutandukanya kugirango itandukane namazi. Imvange ivanze ya toluene na isopropanol murwego rwo hejuru ihindurwa mukigereranyo. Koresha mu buryo butaziguye, hanyuma usubize amazi na isopropanol igisubizo murwego rwo hasi kuri desolventizer kugirango ukoreshe.

Ongeramo acide acetike kuri reaction nyuma yo gusenyuka kugirango uhindure hydroxide ya sodium irenze, hanyuma ukoreshe amazi ashyushye kugirango ukarabe ibikoresho, ukoreshe byimazeyo coagulation iranga selile ya ether mumazi ashyushye kugirango woze ether ya selile, kandi utunganyirize reaction. Ibikoresho binonosoye byoherejwe muburyo bukurikira bwo gutandukana no gukama.

3.4 Kurungurura no gukama

Ibikoresho bitunganijwe byoherezwa kubitandukanya bitambitse na pompe yumuvuduko mwinshi kugirango batandukane amazi yubusa, naho ibikoresho bisigaye byinjira mu cyuma cyumuyaga binyuze mumashanyarazi, hanyuma akumishwa ahuye numwuka ushushe, hanyuma akanyura muri serwakira. gutandukanya n'umwuka Gutandukana, ibikoresho bikomeye byinjira nyuma yo guhonyora.

Amazi yatandukanijwe na horizontal spiral itandukanya yinjira mumazi yo gutunganya amazi nyuma yo gutembera mumatara yimitsi kugirango atandukane selile yanduye.

3.5 Kumenagura no kuvanga

Nyuma yo kumisha, selile ya etherifile izaba ifite ingano zingana zingana, zigomba guhonyorwa no kuvangwa kugirango ingano yikwirakwizwa ryikwirakwizwa hamwe nibigaragara muri rusange byujuje ibyangombwa bisabwa.

3. 6 Ibicuruzwa byarangiye

Ibikoresho byabonetse nyuma yo kumenagura no kuvanga ibikorwa ni selile yuzuye ya selile, ishobora gupakirwa igashyirwa mububiko.

4. Incamake

Amazi yatandukanijwe arimo umunyu runaka, cyane cyane sodium chloride. Amazi yimyanda ihumeka kugirango itandukane umunyu, kandi umwuka wa kabiri wumuyaga urashobora guhurizwa hamwe kugirango ugarure amazi yegeranye, cyangwa urekuwe neza. Ibintu nyamukuru bigize umunyu watandukanijwe ni sodium chloride, nayo irimo urugero rwa acetate ya sodium kubera kutabogama hamwe na acide acike. Uyu munyu ufite agaciro ko gukoresha inganda nyuma yo kongera gukora, gutandukana no kwezwa.