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Izinga lokushisa linamuphi umphumela ku-viscosity yesisombululo samanzi se-HPMC?

IHydroxypropyl Methylcellulose (HPMC) iyi-polymer ebalulekile encibilika emanzini esetshenziswa kabanzi kwezemithi, ukudla, okokugqoka, izinto zokwakha kanye neminye imikhakha. I-viscosity yesixazululo ye-HPMC iyisici esibalulekile esithinta ukusebenza nokusebenza kwayo, futhi izinga lokushisa linomthelela omkhulu ku-viscosity yesisombululo samanzi se-HPMC.

1. Izici ze-viscosity zesisombululo se-HPMC
I-HPMC iyimpahla ye-polymer enezinto zokuncibilika ezibuyiseleka emuva ngokushisa. Lapho i-HPMC incibilika emanzini, isixazululo samanzi esakhiwe sibonisa izici zoketshezi ezingezona eze-Newtonian, okungukuthi, i-viscosity yesixazululo iyashintsha ngokushintsha kwesilinganiso sokugunda. Emazingeni okushisa ajwayelekile, izixazululo ze-HPMC ngokuvamile ziziphatha njengoketshezi lwe-pseudoplastic, okungukuthi, zine-viscosity ephakeme ngamazinga aphansi okugunda, futhi i-viscosity iyancipha njengoba izinga lokugunda likhuphuka.

2. Umphumela wokushisa ku-viscosity yesisombululo se-HPMC
Ukushintsha kwezinga lokushisa kunezindlela ezimbili eziyinhloko zomthelela ku-viscosity yezixazululo zamanzi ze-HPMC: ukwanda kokunyakaza okushisayo kwamaketanga wamangqamuzana kanye nezinguquko ekusebenzisaneni kwesixazululo.

(1) Ukunyakaza okushisayo kwamaketanga wamangqamuzana kuyanda
Lapho izinga lokushisa likhuphuka, ukunyakaza okushisayo kweketango lamangqamuzana e-HPMC kuyanda, okubangela ukuthi amabhondi e-hydrogen kanye ne-van der Waals aphoqelele phakathi kwama-molecule ukuba abe buthaka kanye nokwanda kwe-fluidity yesixazululo. I-viscosity yesisombululo iyancipha ngenxa yokunciphisa ukubopha kanye nokuxhumanisa ngokomzimba phakathi kwamaketanga amangqamuzana. Ngakho-ke, izixazululo ze-HPMC ezinamanzi zibonisa i-viscosity ephansi emazingeni okushisa aphezulu.

(2) Izinguquko ekusebenzisaneni kwesixazululo
Ukushintsha kwezinga lokushisa kungathinta ukunyibilika kwama-molecule e-HPMC emanzini. I-HPMC iyi-polymer enezici ze-thermogelling, futhi ukuncibilika kwayo emanzini kushintsha kakhulu ngezinga lokushisa. Emazingeni okushisa aphansi, amaqembu e-hydrophilic kuchungechunge lwamangqamuzana e-HPMC enza amabhondi e-hydrogen azinzile nama-molecule wamanzi, ngaleyo ndlela agcine ukunyibilika okuhle kanye ne-viscosity ephezulu. Kodwa-ke, lapho izinga lokushisa likhuphuka lifinyelela ezingeni elithile, ukusebenzisana kwe-hydrophobic phakathi kwamaketanga e-molecular HPMC kuyathuthukiswa, okuholela ekwakhekeni kwesakhiwo senethiwekhi esinezinhlangothi ezintathu noma i-gelation esixazululweni, okwenza ukuba i-viscosity yesisombululo ikhule ngokuzumayo ngaphansi kwezimo ezithile. Lesi simo sibizwa ngokuthi "i-thermal gel".

3. Ukubhekwa kokuhlolwa kwezinga lokushisa ku-viscosity yesisombululo se-HPMC
Ucwaningo lokuhlola lubonise ukuthi phakathi kwebanga lokushisa elivamile (isb, 20°C kuya ku-40°C), i-viscosity yezixazululo zamanzi ze-HPMC iyancipha kancane kancane ngezinga lokushisa elikhulayo. Lokhu kungenxa yokuthi amazinga okushisa aphezulu akhuphula amandla e-kinetic amaketanga amangqamuzana futhi anciphise ukusebenzisana kwama-intermolecular, ngaleyo ndlela anciphise ukungqubuzana kwangaphakathi kwesixazululo. Kodwa-ke, lapho izinga lokushisa liqhubeka nokwenyuka lifika endaweni yejeli eshisayo ye-HPMC (imvamisa phakathi kuka-60°C no-90°C, kuye ngezinga lokushintsha kanye nesisindo samangqamuzana e-HPMC), i-viscosity yesixazululo iyanda ngokuzumayo. Ukwenzeka kwalesi simo kuhlobene nokugoqana nokuhlanganisa amaketanga e-molecular HPMC.

4. Ubudlelwano phakathi kwezinga lokushisa kanye nemingcele yesakhiwo ye-HPMC
I-viscosity yesixazululo ye-HPMC ayithinteki kuphela izinga lokushisa, kodwa futhi ihlobene eduze nesakhiwo sayo samangqamuzana. Isibonelo, izinga lokushintsha (okungukuthi, okuqukethwe kwe-hydroxypropyl nama-methyl substituents) nesisindo samangqamuzana e-HPMC kunomthelela obalulekile ekuziphatheni kwayo kwejeli eshisayo. I-HPMC enezinga eliphezulu lokushintsha igcina i-viscosity ephansi ebangeni lokushisa elibanzi ngenxa yamaqembu ayo amaningi e-hydrophilic, kuyilapho i-HPMC enezinga eliphansi lokushintsha inamathuba amaningi okuthi yakhe amajeli ashisayo. Ukwengeza, izixazululo ze-HPMC ezinesisindo se-molecular ephakeme kungenzeka ukuthi zikhuphuke ku-viscosity emazingeni okushisa aphezulu.

5. Ukucatshangelwa Kwezicelo Zezimboni Nezingokoqobo
Ekusetshenzisweni okungokoqobo, izinhlobo ezifanele ze-HPMC zidinga ukukhethwa ngokuvumelana nezimo ezithile zokushisa. Isibonelo, ezindaweni ezinezinga lokushisa eliphezulu, i-HPMC enokumelana nezinga lokushisa okuphezulu idinga ukukhethwa ukuze igweme ukugeleza kwe-thermal. Ngaphansi kwezimo zokushisa eziphansi, ukunyibilika nokuzinza kwe-viscosity kwe-HPMC kudinga ukucatshangelwa.

Umphumela wokushisa ku-viscosity yesisombululo samanzi se-HPMC unokubaluleka okubalulekile okusebenzayo. Emkhakheni wokwenza imithi, i-HPMC ivamise ukusetshenziswa njengento eqhubekayo yokukhishwa kwamalungiselelo emithi, futhi izici zayo ze-viscosity zithinta ngokuqondile izinga lokukhululwa kwezidakamizwa. Embonini yokudla, i-HPMC isetshenziselwa ukuthuthukisa ukuthungwa nokuzinza kwemikhiqizo, futhi ukuncika kwezinga lokushisa kwe-viscosity yayo yesisombululo kudinga ukulungiswa ngokuvumelana nezinga lokushisa lokucubungula. Ezintweni zokwakha, i-HPMC isetshenziswa njenge-ejenti ejiya futhi egcina amanzi, futhi izici zayo ze-viscosity zithinta ukusebenza kokwakhiwa namandla ezinto ezibonakalayo.

Umthelela wezinga lokushisa ku-viscosity yesisombululo samanzi se-HPMC yinqubo eyinkimbinkimbi ehlanganisa ukunyakaza okushisayo kweketango lamangqamuzana, ukusebenzisana kwesisombululo, kanye nezakhiwo zesakhiwo se-polymer. Sekukonke, i-viscosity yezixazululo ezinamanzi ze-HPMC ngokuvamile iyehla ngokwanda kwezinga lokushisa, kodwa kumazinga athile okushisa, i-gelation eshisayo ingase yenzeke. Ukuqonda lesi sici kunokubaluleka kokuqondisa okubalulekile ekusetshenzisweni okungokoqobo kanye nokwenza kahle kwenqubo ye-HPMC.


Isikhathi sokuthumela: Jul-10-2024
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