Inqubo Yokuthola I-Hydroxypropyl Methylcellulose (HPMC)

I-Hydroxypropyl Methylcellulose (HPMC)iyi-ether ye-cellulose engeyona i-ionic esetshenziswa kakhulu, esetshenziswa kabanzi ezintweni zokwakha, kwezemithi, ekudleni, ekumbozeni, nakweminye imikhakha. Ukuqina kokusebenza kwayo kanye nekhwalithi kuthinta ngqo umphumela womkhiqizo wokugcina; ngakho-ke, ukuhlolwa okuhlelekile kwe-HPMC ngesikhathi sokukhiqizwa nokusetshenziswa kubaluleke kakhulu.

1. Ukubukeka kanye nokuhlolwa kwempahla okuyisisekelo

Ngaphambi kokuhlola, isampula iqale ibonwe ngamehlo. I-HPMC esezingeni eliphezulu kufanele ibe yimpuphu emhlophe noma engemhlophe kakhulu enokugeleza okuhle, engenamaqhubu, iphunga, noma ukungcola. Isixazululo sayo samanzi kufanele sibe sobala noma sibe namafu kancane, ngaphandle kwezinto ezilengayo ezisobala. Ngemva kwalokho, okuqukethwe kwayo komswakama kuyanqunywa, ngokuvamile kusetshenziswa i-infrared moisture analyzer noma indlela yokomisa (indlela yesisindo esingaguquki esingu-105℃). Imikhiqizo efanelekile ngokuvamile inokuqukethwe komswakama okungaphansi kuka-5%.

Ukunqunywa kokuqukethwe komlotha kukhombisa okuqukethwe kwayo kokungcola okungaphili. Isampula ishiswa esithandweni somlilo esingenawo umoya ku-550℃ kuya esisindweni esifanayo. Okuqukethwe komlotha ngokuvamile kuyadingeka ukuthi kungadluli ku-1.5%. Okuqukethwe komlotha okweqile kuzothinta ukucaca kwesisombululo kanye nokuqina kwe-viscosity.

2. Ukuhlolwa Kokuqaqamba

Ukuqina kungenye yezinkomba zokusebenza ezibaluleke kakhulu ze-HPMC, okunquma ngqo ukuqina kwayo, ukugcinwa kwamanzi, kanye nemiphumela yokwakha ifilimu. Ukuhlolwa ngokuvamile kwenziwa kusetshenziswa i-viscometer ejikelezayo (njenge-Brookfield viscometer) noma i-Ubbelohde capillary viscometer.

Ngesikhathi sokuhlola, ukuhlushwa okuthile (ngokuvamile okungu-2%) kwesisombululo samanzi se-HPMC kuhlolwa ekushiseni okucacisiwe (ngokuvamile okungu-20 ± 0.1℃). Izinhlobo ezahlukene ze-HPMC zinezinga elihluke kakhulu le-viscosity, njenge-400, 15000, kanye ne-100000 mPa·s. I-viscosity elinganisiwe kufanele ivumelane nobubanzi obujwayelekile bomkhiqizo; ngaphandle kwalokho, kubonisa ukuthi izinga layo le-polymerization noma lokushintsha alizinzile.

3. Izinga Lokuhlolwa Kokufaka Esimweni (Okuqukethwe kwe-Methoxy kanye ne-Hydroxypropoxy)

Ukusebenza kwe-HPMC kunqunywa kakhulu okuqukethwe yizinto ezithatha indawo.
Okuqukethwe kwe-methoxy (–OCH₃) kuthinta ukuncibilika, izinga lokushisa lejeli, kanye nomsebenzi wobuso;
Okuqukethwe kwe-hydroxypropoxy (–OCH₂CHOHCH₃) kuthinta ukuguquguquka kanye nokugcinwa kwamanzi.

Izindlela zokunquma zivame ukusebenzisa i-chemical titration noma i-gas chromatography. Isibonelo, ngemva kwe-acid hydrolysis, isampula iveza utshwala obuhambisanayo, obube sebuhlaziywa ngobuningi nge-titration noma i-chromatography. Imikhiqizo ye-HPMC efanelekile ngokuvamile iqukethe okuqukethwe kwe-methoxyl okungu-19%–24% kanye nokuqukethwe kwe-hydroxypropoxyl okungu-4%–12%.

4. Ukulinganisa Izinga Lokushisa Lejeli

Izici ze-thermogelation ze-HPMC ziyipharamitha ebalulekile eyihlukanisa nezinye i-cellulose ethers. Ngesikhathi sokuhlolwa, isixazululo samanzi se-HPMC siyashiswa kancane futhi sivuselelwe, futhi izinga lokushisa lapho isixazululo sishintsha khona kusuka kokucacile kuya kokushubile liqoshwa njengokushisa kwejeli yaso.

Ngokuvamile, i-HPMC enokuqukethwe okuphezulu kwe-methoxyl inokushisa okuphansi kwejeli, kanti okuqukethwe okuphezulu kwe-hydroxypropoxyl kuholela ekushiseni okuphezulu kwejeli. Lesi sibonakaliso sihlobene nokuzinza komkhiqizo ekusetshenzisweni okufana nodaka lokwakha kanye nopende lwethebhulethi.

5. Ukuhlolwa Kwenani le-pH Nokuncibilika

Ngemva kokulungisa isisombululo se-2% se-HPMC, i-pH yaso ilinganiswa kusetshenziswa imitha ye-pH. Ububanzi obujwayelekile bungu-5.0–8.0. Ngaphakathi kwalolu bubanzi, i-HPMC izinzile futhi ngeke isabele kabi ngezinto eziningi ezingaphili noma izithasiselo.

Ukuhlolwa kokuncibilika kuhlola izinga lokuhlakazeka kwayo kanye nokuncibilika kwayo emanzini abandayo. I-HPMC esezingeni eliphezulu kufanele ihlakazeke ngokushesha ngaphansi kokuxutshwa, yakhe isixazululo esifanayo nesicacile zingakapheli imizuzu engama-30.

6. Ukutholwa Kobumsulwa Nokungcola

Ukutholwa kobumsulwa kufaka phakathi ukuhlolwa kwezinsimbi ezisindayo, ama-chloride, ama-sulfate, kanye nemikhawulo yamagciwane.

Okuqukethwe kwensimbi esindayo (njenge-Pb) ngokuvamile akufanele kudlule u-20 ppm; i-chloride ≤ 0.2%, i-sulfate ≤ 0.5%;

Uma kusetshenziswa imithi noma ukudla, inani eliphelele lamagciwane, amabhaktheriya e-coliform, kanye nenani lesikhunta/lemvubelo kumele lihlolwe ukuqinisekisa ukuphepha.

7. Ukuhlaziywa kwe-Thermogravimetric kanye ne-Fourier Transform Infrared Spectroscopy

Ukuze kuhlolwe kabanzi isakhiwo kanye nokuzinza kokushisa kwe-HPMC, kungasetshenziswa ukuhlaziywa kwe-thermogravimetric (TGA) kanye ne-Fourier transform infrared spectroscopy (FTIR).

I-TGA ingakwazi ukubona ushintsho olukhulu lwe-HPMC emazingeni okushisa ahlukene, ngaleyo ndlela inqume izinga lokushisa layo lokubola kokushisa kanye nobubanzi bokuzinza;

I-FTIR ihlaziya isakhiwo seqembu elisebenzayo ngokusebenzisa iziqongo zokumunca, iqinisekisa ukuba khona kwamabhendi okumunca anezici ze--OH, -OCH₃, kanye ne--OCH₂CHOHCH₃ ukuqinisekisa ukunemba kwesakhiwo sama-molecule.

Ukuhlolwa okuhleliwe okukhulunywe ngakho ngenhla kuvumela ukuhlolwa okuphelele kwezakhiwo ze-physicochemical kanye nokufaneleka kokusetshenziswa kwe-HPMC. Ukuqina, izinga lokufakwa esikhundleni, kanye nokuqukethwe komswakama kuyizinkomba zokulawula ikhwalithi eziyinhloko; kuyilapho i-pH, okuqukethwe komlotha, kanye nokushisa kwe-gelation kubonisa amazinga okucubungula kanye nobumsulwa bawo. Ukunamathela ngokuqinile kulezi zinqubo zokuhlola akugcini nje ngokuqinisekisa ukuzinza komkhiqizo kanye nokusebenza kahle kodwa futhi kunikeza ukwesekwa kwedatha okuthembekile kokuphepha kanyeukusetshenziswa kahle kwe-HPMCezimbonini ezifana nezokwakha, ezemithi, kanye nokudla.