1. Izakhiwo eziyisisekelo ze-HPMC
I-Hydroxypropyl methylcellulose (HPMC)i-nonionic cellulose ether esetshenziswa kabanzi ezintweni zokwakha, imithi, ukudla, izimonyo nezinye izimboni. Izakhiwo zayo eziyingqayizivele ze-physicochemical, ezifana ne-solubility, ukuqina, ukwakheka kwefilimu kanye nezakhiwo ze-gelation ezishisayo, zikwenza kube isithako esiyinhloko emisebenzini eminingi yezimboni. Izinga lokushisa lingenye yezinto eziyinhloko ezithinta ukusebenza kwe-HPMC, ikakhulukazi mayelana ne-solubility, i-viscosity, i-gelation eshisayo kanye nokuzinza kokushisa.
2. Umthelela wezinga lokushisa ekuncibilikeni kwe-HPMC
I-HPMC iyi-polymer encibilikayo e-thermoreversibly, futhi ukuncibilika kwayo kushintsha nezinga lokushisa:
Isimo sokushisa esiphansi (amanzi abandayo): I-HPMC incibilika kalula emanzini abandayo, kodwa izomunca amanzi futhi ivuvuke lapho iqala ukuhlangana namanzi ukuze yakhe izinhlayiya zejeli. Uma ukugovuza kunganele, kungase kwakheke izigaxa. Ngakho-ke, kuvame ukunconywa ukuthi wengeze i-HPMC kancane ngenkathi ugqugquzela ukukhuthaza ukuhlakazeka okufanayo.
Izinga lokushisa elimaphakathi (20-40℃): Kuleli banga lokushisa, i-HPMC inokunyibilika okuhle kanye ne-viscosity ephezulu, futhi ifanele amasistimu ahlukahlukene adinga ukujiya noma ukuqiniswa.
Izinga lokushisa eliphezulu (ngaphezu kuka-60°C): I-HPMC ijwayele ukwenza ijeli eshisayo ekushiseni okuphezulu. Lapho izinga lokushisa lifinyelela izinga lokushisa elithile lejeli, isisombululo sizoba yi-opaque noma sihlanganise, sithinte umphumela wesicelo. Isibonelo, ezintweni zokwakha ezifana nodaka noma i-putty powder, uma izinga lokushisa lamanzi liphezulu kakhulu, i-HPMC ingase ingaqedwa ngokuphumelelayo, ngaleyo ndlela ithinte ikhwalithi yokwakha.
3. Umthelela wezinga lokushisa ku-HPMC viscosity
I-viscosity ye-HPMC ithintwa kakhulu izinga lokushisa:
Ukwenyuka kwezinga lokushisa, ukuncipha kwe-viscosity: I-viscosity yesisombululo se-HPMC imvamisa yehla ngokukhuphuka kwezinga lokushisa. Isibonelo, i-viscosity yesisombululo esithile se-HPMC ingase ibe phezulu ku-20 ° C, kuyilapho ku-50 ° C, i-viscosity yayo izokwehla kakhulu.
Izinga lokushisa liyehla, i-viscosity iyalulama: Uma isisombululo se-HPMC sipholile ngemva kokushisa, i-viscosity yayo izolulama kancane, kodwa ingase ingakwazi ukubuyela ngokuphelele esimweni sokuqala.
I-HPMC yamabanga ahlukene e-viscosity iziphatha ngendlela ehlukile: i-HPMC ene-viscosity ephezulu izwela kakhulu ekushintsheni kwezinga lokushisa, kuyilapho i-HPMC ene-viscosity ephansi inokuguquguquka okuncane kwe-viscosity lapho izinga lokushisa lishintsha. Ngakho-ke, kubaluleke kakhulu ukukhetha i-HPMC ene-viscosity efanele ezimweni ezihlukene zohlelo lokusebenza.
4. Umthelela wezinga lokushisa ku-gelation eshisayo ye-HPMC
Isici esibalulekile se-HPMC yi-gelation eshisayo, okungukuthi, lapho izinga lokushisa likhuphuka lifika ezingeni elithile, isisombululo salo sizophenduka ijeli. Lokhu kushisa kuvame ukubizwa ngokuthi izinga lokushisa le-gelation. Izinhlobo ezahlukene ze-HPMC zinamazinga okushisa e-gelation ahlukene, ngokuvamile aphakathi kuka-50-80℃.
Ezimbonini zokudla nemithi, lesi sici se-HPMC sisetshenziselwa ukulungisa izidakamizwa ezikhishwa isikhathi eside noma ama-colloid okudla.
Ezicelweni zokwakha, ezifana nosimende nodaka lwe-putty, i-gelation eshisayo ye-HPMC inganikeza ukugcinwa kwamanzi, kodwa uma izinga lokushisa lendawo yokwakha liphezulu kakhulu, i-gelation ingase ithinte umsebenzi wokwakha.
5. Umthelela wezinga lokushisa ekuzinzeni okushisayo kwe-HPMC
Isakhiwo samakhemikhali se-HPMC sizinzile phakathi kwebanga lokushisa elifanele, kodwa ukuchayeka isikhathi eside kumazinga okushisa aphezulu kungase kubangele ukuwohloka.
Izinga lokushisa eliphakeme lesikhathi esifushane (elifana nokushisisa ngokushesha ukuya ngaphezu kuka-100℃): lingase lingathinti kakhulu izakhiwo zamakhemikhali ze-HPMC, kodwa lingabangela izinguquko ezimpahleni ezibonakalayo, ezifana nokuncipha kwe-viscosity.
Izinga lokushisa eliphakeme lesikhathi eside (njengokushisa okuqhubekayo ngaphezu kuka-90℃): kungabangela ukwephuka kweketango lamangqamuzana e-HPMC, okuholela ekwehleni okungenakuhlehliswa kwe-viscosity, kukhinyabeze ukujiya kwayo nokwenza ifilimu.
Izinga lokushisa eliphakeme kakhulu (ngaphezu kuka-200℃): I-HPMC ingase ibole ngokushisa, ikhiphe izinto eziguquguqukayo njenge-methanol ne-propanol, futhi ibangele ukuthi okokusebenza kushintshe umbala noma ngisho ne-carbonize.
6. Izincomo zohlelo lokusebenza lwe-HPMC ezindaweni ezihlukene zokushisa
Ukuze unikeze ukudlala okugcwele ekusebenzeni kwe-HPMC, izinyathelo ezifanele kufanele zithathwe ngokuya ngezimo ezihlukene zokushisa:
Ezimweni zokushisa eziphansi (0-10℃): I-HPMC incibilika kancane, futhi kuyanconywa ukuyincibilikisa ngaphambili emanzini afudumele (20-40℃) ngaphambi kokusetshenziswa.
Ezimweni zokushisa ezijwayelekile (10-40℃): I-HPMC inokusebenza okuzinzile futhi ilungele ukusetshenziswa okuningi, okufana nama-coatings, ama-mortars, ukudla kanye nezinto ezisizayo zemithi.
Endaweni yokushisa ephezulu (ngaphezulu kuka-40℃): Gwema ukwengeza i-HPMC ngokuqondile kuketshezi lokushisa eliphezulu. Kunconywa ukuyincibilikisa emanzini abandayo ngaphambi kokuyishisisa, noma ukhethe i-HPMC ekwazi ukumelana nezinga lokushisa eliphezulu ukuze unciphise umthelela we-thermal gelation kuhlelo lokusebenza.
Izinga lokushisa linomthelela omkhulu ku-solubility, viscosity, gelation eshisayo kanye nokuzinza kokushisa kwe-thermal.I-HPMC. Ngesikhathi senqubo yokufaka isicelo, kuyadingeka ukukhetha ngokunengqondo imodeli nendlela yokusetshenziswa kwe-HPMC ngokuya ngezimo ezithile zokushisa ukuze kuqinisekiswe ukusebenza kwayo okuhle. Ukuqonda ukuzwela kwezinga lokushisa kwe-HPMC akukwazi nje ukuthuthukisa ikhwalithi yomkhiqizo, kodwa futhi kugweme ukulahlekelwa okungadingekile okubangelwa ukushintsha kwezinga lokushisa futhi kuthuthukise ukusebenza kahle kokukhiqiza kanye nezinzuzo zezomnotho.
Isikhathi sokuthumela: Mar-28-2025