I-Hydroxypropyl methylcellulose (HPMC)iyi-ether ebalulekile ye-nonionic cellulose esetshenziswa kabanzi ekwakheni, emithini yemithi, ekudleni, nakumakhemikhali ansuku zonke. Ukuqina kuyinkomba ebalulekile yokuhlola ikhwalithi kanye nokusebenza kwe-HPMC. Ayibonisi nje kuphela izakhiwo ze-rheological zesisombululo sayo kodwa futhi ihlobene ngqo nokujiya kwayo, ukugcinwa kwamanzi, kanye nezakhiwo zokwakha ifilimu. Ukuqinisekisa ikhwalithi yomkhiqizo ehambisanayo, ukulinganiswa kwe-viscosity kumele kwenziwe kusetshenziswa indlela yokuhlola i-viscosity yesayensi nejwayelekile.
1. Isimiso Sokuhlola
I-HPMC iyancibilika emanzini ukuze yakhe isixazululo esibonakalayo noma esikhanyayo. Ukuqina kwayo kuncike kakhulu ezingeni le-polymerization, izinga lokushintsha, kanye nokuhlushwa kwesisombululo. Ukuhlolwa kokuqina kuveza izakhiwo zokugeleza kwesisombululo se-HPMC ngokulinganisa ukungqubuzana kwangaphakathi kwesisombululo ngesikhathi sokugeleza ekushiseni okuthile. Ukulinganisa kuvame ukwenziwa kusetshenziswa i-viscometer ejikelezayo (uhlobo lweBrookfield) noma i-viscometer ye-capillary. Indlela ejikelezayo isetshenziswa kakhulu, njengoba inikeza ukuqonda okunembile kwezakhiwo zokunciphisa ukusika kwesisombululo ngesivinini esihlukile sokujikeleza.
2. Izindinganiso Ezivamile Nezimo Zokuhlola
Njengamanje, ukuhlolwa kwe-HPMC viscosity kusekelwe kakhulu kulokhu okulandelayo:
Izinga lesiShayina: GB/T 12000 “Izindlela Zokuhlola Ezijwayelekile ze-Cellulose Ethers”
Izinga lase-US: I-ASTM D1347 “Izindlela Zokuhlola Ezijwayelekile Zezixazululo ze-Cellulose Ether”
Umkhuba wemboni: Ukuqina kukalwa kusetshenziswa isixazululo samanzi esingu-2% ku-20°C kusetshenziswa i-Brookfield rotational viscometer.
Ukuhlushwa kwesisombululo sokuhlola ngokuvamile kungu-2% (ingxenye yesisindo), kodwa amazinga ahlukene e-HPMC angadinga nokulinganiswa ku-1%, 2%, noma amazinga aphezulu. Izinga lokushisa lokuhlola kumele lilawulwe ngokuqinile ku-20±0.1°C, njengoba ukuguquguquka kwezinga lokushisa kungathinta kakhulu ukufundwa kwe-viscosity.
3. Inqubo Yokuhlola
3.1. Ukulungiswa Kwe-Reagent Nokusetshenziswa Kwethuluzi
Ibhalansi yokuhlaziya enembile (ukunemba okungu-0.1 mg)
I-Brookfield rotational viscometer (uchungechunge lwe-LV olutholakala kakhulu)
3.2. Ibhavu lamanzi elinokushisa okuhlala njalo noma indawo elawulwa ukushisa
Amanzi ahlanziwe (ahlangabezana nezidingo zamanzi ze-GB/T 6682 Grade III)
Hlanza i-beaker ne-stirrer
3.3. Ukulungiselela Isixazululo
Kala ngokunembile isampula ye-HPMC engu-2.00 g (± 0.01 g).
Faka cishe u-80% womthamo wamanzi ahlanzekile (cishe u-80 mL) ebhekheni bese ushisa cishe u-80°C. Fafaza kancane kancane i-HPMC ebhekheni ngenkathi uvuselela ukuze ugweme ukugoqana.
Qhubeka uvuselela kuze kube yilapho i-HPMC imanziswe kahle futhi ihlakazeke. Bese ufaka inani elisele lamanzi abandayo bese upholisa ekamelweni lokushisa, ulethe inani eliphelele ku-100 mL.
Faka ikhambi esiqandisini ku-4°C ubusuku bonke ukuze uvumele ukuvuvukala okuphelele futhi ususe amabhamuza omoya.
3.4. Ukulinganiswa Kokugoba
Dlulisa ikhambi ebhavini lamanzi elinokushisa okungaguquki, ugcine izinga lokushisa elingu-20 ± 0.1°C. Khetha i-spindle efanele (ngokuvamile uNombolo 2 noma uNombolo 3) kanye nesivinini (ngokuvamile u-30 rpm).
Qala i-viscometer bese uqopha ukufundwa ngemva kokuba inaliti isizinzile. Phinda isilinganiso ngasinye kathathu, bese uthatha isilinganiso njengomphumela wokugcina.
Uma ukufundwa kudlula ububanzi bethuluzi, shintsha i-spindle noma ulungise ukuhlushwa bese ulinganisa kabusha.
4. Izinyathelo Zokuqapha
Ukulawula izinga lokushisa kubalulekile. Uma izinga lokushisa likhuphuka ngo-1°C, i-viscosity iyancipha cishe ngo-2% kuya ku-3%.
Isixazululo kumele sincibilike ngokuphelele futhi singabi namabhamuza, ngaphandle kwalokho ukufundwa kuzoba kuphansi noma kuyashintshashintsha.
I-HPMC ibonisa izakhiwo zokunciphisa ukucheba, ngakho-ke isivinini nesikhathi sokulinganisa kufanele sigcinwe njalo.
Amanzi asetshenziswayo kumele angabi nokungcola nama-ion ukuze kugwenywe ukuthinta ukuncibilika nokufundwa kwawo.
Ithuluzi kufanele lilinganiswe njalo, futhi isipina kanye nesitsha sesampula kufanele kugcinwe kuhlanzekile.
5. Ukuhlaziywa Kwezinto Ezithonyayo
Izinga Lokwenziwa Kwe-polymerization kanye Nezinga Lokufakwa Kwe-substitution: Uma izinga lokwenziwa kwe-polymerization ye-HPMC liphezulu, uchungechunge lwama-molecule luba lude futhi i-viscosity yesisombululo iba nkulu. Izinga lokwenziwa kwe-methoxy kanye ne-hydroxypropoxy liphinde lithinte ukuguquguquka kwayo kanye nesakhiwo sesisombululo.
Ukuhlushwa: Ukuhlushwa kwesisombululo kanye nokuhlushwa kuhlobene kakhulu, futhi ngisho nezinguquko ezincane ekuhlushwa kungathinta kakhulu imiphumela yokuhlolwa. Izinga lokushisa kanye ne-pH: Ukwanda kwezinga lokushisa kunciphisa ukuhlushwa, kuyilapho izinguquko ze-pH ngokuvamile zinomthelela omncane ekuhlushweni kwe-HPMC ngoba iyi-non-ionic cellulose ether.
Isixazululo Ukuguga: Ukuqina kungase kwehle kancane ngemva kokugcinwa isikhathi eside. Kunconywa ukuthi ukuhlolwa kuqedwe zingakapheli amahora angu-24 kusukela kulungiselelwe.
6. Ukwethulwa Kwemiphumela Nokusetshenziswa
Imiphumela yokuhlolwa ivezwa nge-mPa·s (milliPascals·seconds), isibonelo, “isixazululo esingu-2%, 20°C, 20,000 mPa·s.” Ezisetshenzisweni zezimboni,I-HPMCAmabanga e-viscosity avame ukuvezwa ngezinkulungwane, njenge-400 cps kanye ne-20,000 cps. Abasebenzisi bangakhetha amabanga ahlukene ngokusekelwe ezidingweni zohlelo lokusebenza kanye nomklamo wokwakha.
Isikhathi sokuthunyelwe: Julayi-30-2025