IHydroxypropyl methylcellulose (HPMC) i-nonionic cellulose ether eyenziwe nge-cellulose ngokuguqulwa kwamakhemikhali. Njengento ebalulekile ye-polymer encibilika emanzini, i-HPMC isetshenziswa kabanzi ekwakhiweni, kwezemithi, ekudleni, kwezimonyo nakweminye imikhakha. Ukuziphatha kwe-HPMC emanzini kubaluleke kakhulu ngoba inquma umphumela wayo wokusebenzisa esixazululweni, okuhlanganisa ukuqina, ukumiswa, ukubopha kanye nekhono lokwenza ifilimu.
Indlela yokuvuvukala ye-HPMC emanzini
I-HPMC izovuvuka kakhulu emanzini. Lokhu kuvuvukala kubangelwa ikakhulukazi ukuhlangana kwe-hydrogen phakathi kwamaqembu e-hydroxyl kanye ne-methoxy esakhiweni samangqamuzana e-HPMC nama-molecule amanzi. Lapho i-HPMC ihlangana namanzi, ama-molecule amanzi azongena phakathi kwamaketanga ama-molecule e-HPMC, aphule izibopho ze-hydrogen phakathi kwama-molecule, elule izingxenye zamaketango futhi akhulise ivolumu yamangqamuzana. Le nqubo yilokho esikubiza ngokuthi "ukuvuvukala" okwenzekayo.
Ngokuqondile, lapho i-HPMC ikhukhumala emanzini, iqala ukumunca amanzi futhi iqale ukuvuvukala, bese kancane kancane yakha isisombululo se-viscous colloidal. Le nqubo ihlanganisa izigaba ezimbili eziyinhloko: esinye isigaba sokuqala sokuvuvukala esisheshayo, kanti esinye isigaba esilandelayo sokuncibilika kancane kancane. Esigabeni sokuqala, i-HPMC imunca amanzi ukuze yakhe ama-hydrates avuvukele, inqubo evamise ukuqedwa phakathi nemizuzu embalwa. Kulesi sigaba, ama-molecule amanzi angena ngokushesha ezinhlayiyeni ze-HPMC, okwenza umthamo wawo wande. Njengoba amanzi engena ngokuqhubekayo, ama-molecule e-HPMC ahlukana kancane kancane nezinhlayiya eziqinile futhi afake isixazululo ukuze akhe isixazululo samanzi esifanayo.
Izinto ezithinta ukuvuvukala kwe-HPMC emanzini
Izinga lokushisa: Izinga lokushisa linomthelela omkhulu ekuziphatheni kokuvuvukala kwe-HPMC emanzini. Ngokuvamile, njengoba izinga lokushisa likhuphuka, izinga lokuqedwa kwe-HPMC liyashesha futhi izinga lokuvuvukala libonakala ngokucacile. Lokhu kungenxa yokuthi amandla e-kinetic ama-molecule amanzi akhuphuka emazingeni okushisa aphezulu, okwenza kube lula ukungena phakathi kwezingxenye zama-molecule e-HPMC futhi akhuthaze ukwanda kwawo. Nokho, izinga lokushisa eliphezulu kakhulu lingabangela ukuwohloka kwengxenye ye-HPMC futhi kuthinte izici zayo zokuncibilika.
Ibanga le-Viscosity: I-HPMC inamabanga ahlukahlukene we-viscosity. Uma iphezulu i-viscosity ye-HPMC, yilapho isixazululo se-colloidal sibonakala kakhulu lapho sivuvukala emanzini. Lapho i-HPMC enezinga eliphezulu le-viscosity ikhukhumala, ama-molecule amanzi angena kancane futhi inqubo yokuhlakazeka iba yinde ngokuhambisanayo. I-HPMC enezinga eliphansi le-viscosity kulula ukuyincibilikisa futhi yakha isixazululo esincanyana.
Inani le-pH lesixazululo: I-HPMC inokuguquguquka okuthile ku-pH value. I-HPMC inomphumela ongcono wokuvuvukala ngaphansi kwezimo ze-asidi ezingathathi hlangothi noma ezibuthakathaka. Ngaphansi kwe-asidi eqinile noma izimo ze-alkaline ezinamandla, ukwakheka kwamangqamuzana e-HPMC kungase kushintshe, ngaleyo ndlela kuthinte ukuziphatha kwayo kokuvuvukala nokuhlakazeka.
Ukugxila: Ukugxila kwesisombululo se-HPMC emanzini kuphinde kuthinte ukuziphatha kwayo kokuvuvukala. Ezimweni eziphansi, i-HPMC kulula ukuhlakazeka ngokuphelele futhi yakhe isisombululo esifanayo. Ezimweni eziphakeme, ukusebenzisana phakathi kwama-molecule e-HPMC kuyanda, okungase kubangele ukuthi amanye ama-molecule kube nzima ukuncibilika ngokuphelele emanzini futhi akhe amabhulokhi ejeli.
Isicelo esiwusizo sokuvuvukala kwe-HPMC
Izici zokuvuvuka ze-HPMC zidlala indima ebalulekile ekusebenzeni okungokoqobo. Isibonelo, embonini yezemithi, i-HPMC isetshenziswa kakhulu kumathebulethi akhishwa isikhathi eside. Ngenxa yokuthi ikhukhumala emanzini ukuze yenze ifilimu ye-colloidal, ingakwazi ukulawula ngokuphumelelayo izinga lokukhululwa komuthi, ngaleyo ndlela yandise ubude besikhathi sokusebenza kwezidakamizwa.
Embonini yezokwakha, i-HPMC ivamise ukusetshenziswa njengendawo yokuqinisa kanye nokugcina amanzi kusimende nezinto ezisekelwe ku-gypsum. Izakhiwo zayo zokuvuvukala zingathuthukisa ukunamathela nokusebenza kokwakhiwa kwezinto, kuyilapho futhi igcina umswakama, yandisa isikhathi sokumisa sezinto zokwakha, futhi ithuthukisa amandla emishini kanye nokushelela komhlaba kwemikhiqizo eqediwe.
Ezimbonini zokudla nezimonyo, i-HPMC nayo idlala indima ebalulekile njengokujiya nokuqiniswa. Ukuziphatha kwayo kokuvuvukala kunganikeza ukudla ukunambitheka nokuthungwa okungcono, kuyilapho kuzimonyo, i-HPMC isiza ukwenza umphumela wokufaka isicelo ofanayo futhi igcine umswakama.
Ukuziphatha kokuvuvukala kwe-HPMC emanzini kuwumphumela wokuxhumana phakathi kwesakhiwo sayo samakhemikhali nama-molecule amanzi. Ngokulungisa izici ezifana nezinga lokushisa, inani le-pH, ibanga le-viscosity kanye nokugxila kwesixazululo, inqubo yokuvuvukala nokuqedwa kwe-HPMC emanzini ingalawulwa ukuze kuhlangatshezwane nezidingo zezindawo ezihlukene zokufaka isicelo. Le ndawo yokuvuvukala ye-HPMC isetshenziswa kabanzi ezimbonini eziningi, ikhombisa ukubaluleka kwayo njengento esebenzayo ye-polymer.
Isikhathi sokuthumela: Aug-29-2024