Ukulungiswa kwe-cellulose ethers
Ukulungiswa kwei-cellulose etherskubandakanya ukuguqula ngamakhemikhali i-polymer cellulose yemvelo ngokusabela kwe-etherification. Le nqubo yethula amaqembu e-ether emaqenjini e-hydroxyl eketango le-cellulose polymer, okuholela ekwakhekeni kwama-cellulose ether anezakhiwo ezihlukile. Ama-cellulose ether ajwayeleke kakhulu ahlanganisa i-Hydroxypropyl Methylcellulose (HPMC), Carboxymethyl Cellulose (CMC), Hydroxyethyl Cellulose (HEC), Methyl Cellulose (MC), kanye ne-Ethyl Cellulose (EC). Nakhu ukubuka konke okujwayelekile kwenqubo yokulungiselela:
1. Ukuthola iCellulose:
- Inqubo iqala ngokuthola i-cellulose, ngokuvamile etholakala ku-pulp yokhuni noma ukotini. Ukukhethwa komthombo we-cellulose kungaba nomthelela ezinhlelweni zomkhiqizo wokugcina we-cellulose ether.
2. Ukudonsa:
- I-cellulose ingaphansi kwezinqubo ze-pulping ukuze iphule imicu ibe yindlela elawulekayo. Lokhu kungase kuhlanganise izindlela zokudonsa ngomshini noma ngamakhemikhali.
3. Ukuhlanzwa:
- I-cellulose iyahlanzwa ukuze isuse ukungcola, i-lignin, nezinye izakhi ezingezona i-cellulosic. Lesi sinyathelo sokuhlanza sibalulekile ekutholeni impahla ye-cellulose yekhwalithi ephezulu.
4. Ukusabela kwe-Etherification:
- I-cellulose ehlanzekile idlula i-etherification, lapho amaqembu e-ether ethulwa emaqenjini e-hydroxyl kuketango le-cellulose polymer. Ukukhethwa kwe-etherifying agent kanye nezimo zokusabela kuncike emkhiqizweni we-cellulose ether oyifunayo.
- Ama-etherifying agents ajwayelekile ahlanganisa i-ethylene oxide, i-propylene oxide, i-sodium chloroacetate, i-methyl chloride, nabanye.
5. Ukulawulwa Kwezinhlaka Zokusabela:
- Ukusabela kwe-etherification kulawulwa ngokucophelela ngokwezinga lokushisa, ingcindezi, kanye ne-pH ukuze kuzuzwe izinga elifiswayo lokushintshwa (DS) futhi kugwenywe ukusabela okuseceleni.
- Izimo ze-alkaline zivame ukusetshenziswa, futhi i-pH yengxube yokusabela iqashwe ngokucophelela.
6. Ukungathathi hlangothi kanye Nokugeza:
- Ngemuva kokusabela kwe-etherification, umkhiqizo uvamise ukuncishiswa ukuze kukhishwe ama-reagents amaningi noma imikhiqizo ekhiqizwayo. Lesi sinyathelo silandelwa ukugeza ngokuphelele ukuze kuqedwe amakhemikhali ayinsalela nokungcola.
7. Ukomisa:
- I-cellulose ehlanziwe ne-etherified yomiswa ukuze kutholwe umkhiqizo wokugcina we-cellulose ether uyimpushana noma ifomu le-granular.
8. Ukulawulwa Kwekhwalithi:
- Kusetshenziswa amasu okuhlaziya ahlukahlukene ekulawuleni ikhwalithi, okuhlanganisa i-spectroscopy ye-nuclear magnetic resonance (NMR), i-Fourier-transform infrared infrared (FTIR) spectroscopy, kanye ne-chromatography.
- I-degree of substitution (DS) iyipharamitha ebalulekile eqashwe ngesikhathi sokukhiqiza ukuze kuqinisekiswe ukuvumelana.
9. Ukwakhiwa kanye Nokupakishwa:
- I-cellulose ether ibe isilungiswa ibe amabanga ahlukene ukuze ihlangabezane nezimfuneko ezithile zezinhlelo zokusebenza ezihlukahlukene. Imikhiqizo yokugcina iyapakishwa ukuze isatshalaliswe.
Ukulungiswa kwe-cellulose ethers kuyinqubo yamakhemikhali eyinkimbinkimbi edinga ukulawulwa ngokucophelela kwezimo zokusabela ukuze kuzuzwe izakhiwo ezidingekayo. Ukuguquguquka kwe-cellulose ethers kuvumela ukusetshenziswa kwawo ezinhlobonhlobo zezinhlelo zokusebenza kuzo zonke izimboni, okuhlanganisa ezemithi, ukudla, ukwakhiwa, ama-coatings, nokuningi.
Isikhathi sokuthumela: Jan-20-2024