IHydroxypropyl Methylcellulose (HPMC) iwukuphuma kwe-cellulose okuvame ukusetshenziswa okunezinhlobonhlobo zezinhlelo zokusebenza, njengemithi, ukudla, izinto zokwakha kanye nezimonyo. I-HPMC i-non-ionic, i-semi-synthetic, i-polymer engasebenzi kahle kakhulu nokuncibilika kwamanzi, ukujiya, ukunamathela kanye nezakhiwo zefilimu.
Isakhiwo kanye nezakhiwo ze-HPMC
I-HPMC iyiselulosi eshintshiwe ekhiqizwa ngokuphendula i-cellulose nge-methyl chloride ne-propylene oxide. Isakhiwo sayo samangqamuzana siqukethe kokubili i-methyl kanye ne-hydroxypropyl substituents, enikeza i-HPMC izici eziyingqayizivele zomzimba namakhemikhali, njengokuncibilika okuhle kakhulu, ukuvikelwa kwe-colloid kanye nezakhiwo zefilimu. I-HPMC ingahlukaniswa ngokucaciswa okuningi ngokuya kwezindawo ezihlukile, futhi ukucaciswa ngakunye kunokuncibilika okuhlukile kanye nokusetshenziswa emanzini.
Ukuncibilika kwe-HPMC emanzini
Indlela yokuhlakaza
I-HPMC isebenzisana nama-molecule wamanzi ngamabhondi e-hydrogen ukuze yakhe isixazululo. Inqubo yayo yokuqedwa ihlanganisa ama-molecule amanzi angena kancane kancane phakathi kwamaketanga e-molecular of HPMC, acekele phansi ukuhlangana kwawo, ukuze amaketanga e-polymer ahlakazeke emanzini ukuze enze isisombululo esifanayo. I-solubility ye-HPMC ihlobene eduze nesisindo sayo samangqamuzana, uhlobo olungena esikhundleni kanye nezinga lokushintshwa (DS). Ngokuvamile, ukuphakama kwezinga lokushintshwa kwe-substitute, kuyanda ukuncibilika kwe-HPMC emanzini.
Umthelela wezinga lokushisa ekuncibilikeni
Izinga lokushisa lingenye yezinto ezibalulekile ezithinta ukunyibilika kwe-HPMC. Ukuncibilika kwe-HPMC emanzini kubonisa izici ezihlukene njengoba izinga lokushisa lishintsha:
Ibanga lokushisa lokuncibilika: I-HPMC inzima ukuncibilika emanzini abandayo (ngokuvamile ngaphansi kuka-40°C), kodwa ingancibilika ngokushesha uma ishisiswe ibe ngu-60°C noma ngaphezulu. Nge-HPMC ene-viscosity ephansi, izinga lokushisa lamanzi elicishe libe ngu-60°C livamise ukuba izinga lokushisa elifanele lokuncibilika. Nge-HPMC ene-viscosity ephezulu, izinga lokushisa elilungile lokuncibilika lingase libe phezulu njengo-80°C.
I-Gelation ngesikhathi sokupholisa: Uma isixazululo se-HPMC sishisiswe ezingeni lokushisa elithile (imvamisa engu-60-80 ° C) ngesikhathi sokuncibilika bese sipholiswa kancane, ijeli eshisayo izokwakhiwa. Le jeli eshisayo iyazinza ngemva kokupholisa ekamelweni lokushisa futhi ingaphinde ihlakazwe emanzini abandayo. Lesi simo sibaluleke kakhulu ekulungiseni izixazululo ze-HPMC ngezinjongo ezithile ezithile (njengamaphilisi akhipha izidakamizwa).
Ukusebenza kahle kokuhlakazwa: Ngokuvamile, amazinga okushisa aphezulu angasheshisa inqubo yokuqedwa kwe-HPMC. Kodwa-ke, izinga lokushisa eliphakeme kakhulu lingaholela ekonakaleni kwe-polymer noma ukwehla kwe-viscosity yokuhlakazeka. Ngakho-ke, ekusebenzeni kwangempela, izinga lokushisa elifanele lokuchithwa kufanele likhethwe njengoba lidingeka ukuze kugwenywe ukucekelwa phansi okungadingekile kanye nezinguquko zempahla.
Umthelela we-pH ekuncibilikeni
Njenge-polymer engeyona i-ionic, ukuncibilika kwe-HPMC emanzini akuthintwa ngokuqondile ivelu ye-pH yesixazululo. Kodwa-ke, izimo ze-pH ezidlulele (ezifana nezindawo ezine-asidi eqinile noma ezine-alkali) zingathinta izici zokuhlakazeka ze-HPMC:
Izimo ezine-asidi: Ngaphansi kwezimo ezine-asidi eqinile (pH <3), amanye amabhondi amakhemikhali e-HPMC (njengamabhondi e-ether) angase abhujiswe i-acidic medium, ngaleyo ndlela kuthinte ukunyibilika nokuhlakazeka kwayo. Nokho, kububanzi obujwayelekile be-asidi ebuthaka (pH 3-6), i-HPMC isengancibilika kahle. Izimo ze-alkaline: Ngaphansi kwezimo eziqinile ze-alkaline (pH> 11), i-HPMC ingase yonakale, okuvamise ukuba ngenxa yokusabela kwe-hydrolysis yeketango le-hydroxypropyl. Ngaphansi kwezimo ze-alkali ezibuthakathaka (pH 7-9), ukunyibilika kwe-HPMC ngokuvamile akuthinteki kakhulu.
Indlela yokuhlakaza ye-HPMC
Ukuze kuqedwe ngempumelelo i-HPMC, izindlela ezilandelayo zivame ukusetshenziswa:
Indlela yokusabalalisa amanzi abandayo: Faka kancane kancane i-HPMC powder emanzini abandayo ngenkathi ugqugquzela ukuze uyihlakaze ngokulinganayo. Le ndlela ingavimbela i-HPMC ukuthi ihlangane ngokuqondile emanzini, futhi isixazululo sakha ungqimba oluvikelayo lwe-colloidal. Bese, kancane kancane uyishise ibe ngu-60-80 ° C ukuze uyiqede ngokuphelele. Le ndlela ifanele ukuhlakazwa kwe-HPMC eminingi.
Indlela yokusabalalisa amanzi ashisayo: Engeza i-HPMC emanzini ashisayo bese uwanyakazisa ngokushesha ukuze awancibilikise ngokushesha ezingeni lokushisa eliphezulu. Le ndlela ifanele i-HPMC ene-viscosity ephezulu, kodwa kufanele kukhokhwe ekulawuleni izinga lokushisa ukuze kugwenywe ukuwohloka.
Isixazululo Indlela yokulungiselela ngaphambilini: Okokuqala, i-HPMC incibilika ku-solvent yemvelo (njenge-ethanol), bese amanzi engezwa kancane kancane ukuze aguqulwe abe yisixazululo esinamanzi. Le ndlela ilungele izimo zohlelo lokusebenza ezinezidingo eziphezulu zokuncibilika.
Umkhuba wokuqedwa kwezinhlelo zokusebenza ezingokoqobo
Ezinhlelweni ezisebenzayo, inqubo yokuhlakazwa kwe-HPMC idinga ukuthuthukiswa ngokuya ngokusetshenziswa okuthile. Isibonelo, emkhakheni wezokwelapha, ngokuvamile kuyadingeka ukwakha isisombululo se-colloidal esifana kakhulu futhi esizinzile, futhi ukulawulwa okuqinile kwezinga lokushisa ne-pH kuyadingeka ukuze kuqinisekiswe i-viscosity kanye nomsebenzi we-biological wesixazululo. Ezintweni zokwakha, ukuncibilika kwe-HPMC kuthinta izakhiwo zokwakha ifilimu namandla acindezelayo, ngakho-ke indlela engcono kakhulu yokuhlakaza idinga ukukhethwa ngokuhambisana nezimo ezithile zemvelo.
Ukuncibilika kwe-HPMC emanzini kuthintwa izinto eziningi, ikakhulukazi izinga lokushisa ne-pH. Ngokuvamile, i-HPMC incibilika ngokushesha emazingeni okushisa aphezulu (60-80°C), kodwa ingase yehlise izinga noma incibilike kancane ngaphansi kwezimo ze-pH ezidlulele. Ngakho-ke, ekusetshenzisweni okungokoqobo, kuyadingeka ukukhetha izinga lokushisa elifanele lokuchithwa kanye nebanga le-pH ngokuya ngokusetshenziswa okukhethekile nezimo zemvelo ze-HPMC ukuze kuqinisekiswe ukunyibilika kwayo okuhle nokusebenza kwayo.
Isikhathi sokuthumela: Jun-25-2024