I-HPMC iyi-hydroxypropyl methylcellulose, okuyi-ether engeyona i-ionic cellulose eyenziwe ngokotini ocolisisiwe ngemva kokwenziwa kwe-alkalization, kusetshenziswa i-propylene oxide ne-methyl chloride njengama-etherification agents, futhi ngochungechunge lokusabela. Izinga lokushintsha ngokuvamile liyi-1.2 ~ 2.0. Izakhiwo zayo zihlukile ngenxa yezilinganiso ezihlukene zokuqukethwe kwe-methoxyl nokuqukethwe kwe-hydroxypropyl.
I-MC yi-methyl cellulose, eyenziwe ngayoi-cellulose etherngokwelapha ukotini ocolisisiwe nge-alkali, kusetshenziswa i-methane chloride njenge-etherification agent, kanye nokudlula ochungechungeni lokusabela. Ngokuvamile, izinga lokushintsha lingu-1.6~2.0, futhi ukunyibilika nakho kuhlukile ngamazinga ahlukene okushintsha. Kungokwe-non-ionic cellulose ether.
Ukuqhathaniswa kokusebenza phakathi kwalokhu okubili:
(1) IHydroxypropyl methylcellulose incibilika kalula emanzini abandayo, futhi izohlangabezana nobunzima ekuncibilikeni emanzini ashisayo. Kodwa izinga lokushisa layo le-gelation emanzini ashisayo liphakeme kakhulu kunalelo le-methyl cellulose. I-solubility emanzini abandayo nayo ithuthuke kakhulu uma iqhathaniswa ne-methyl cellulose. I-Hydroxypropyl methylcellulose izinzile ku-asidi ne-alkali, futhi isixazululo sayo esinamanzi sizinze kakhulu kububanzi be-pH=2~12. I-Caustic soda namanzi e-lime anethonya elincane ekusebenzeni kwawo, kodwa i-alkali ingasheshisa ukuchithwa kwayo futhi ikhulise ukubukeka kwayo. IHydroxypropyl methylcellulose izinzile kusawoti ovamile, kodwa lapho ukuhlangana kwesixazululo sikasawoti kuphezulu, i-viscosity ye-hydroxypropyl methylcellulose solution ivame ukwanda.
I-Methylcellulose nayo iyancibilika emanzini abandayo, futhi kuyoba nzima ukuyichitha emanzini ashisayo. Isixazululo saso esinamanzi sizinzile kakhulu ebangeni le-pH=3~12. Inokuhambisana okuhle nesitashi, i-guar gum, njll kanye nama-surfactants amaningi. Lapho izinga lokushisa lifinyelela izinga lokushisa le-gelation, i-gelation iyenzeka.
(2) I-viscosity ye-hydroxypropyl methylcellulose ihlobene nesisindo sayo samangqamuzana, futhi uma sikhulu isisindo samangqamuzana, i-viscosity iphakama. Ukushisa nakho kuthinta i-viscosity yayo, njengoba izinga lokushisa likhuphuka, i-viscosity iyancipha. Kodwa-ke, i-viscosity yayo ephezulu inomphumela ophansi wokushisa kune-methyl cellulose. Isixazululo saso sizinzile uma sigcinwe ekamelweni lokushisa.
I-Methylcellulose inomthelela omkhulu ekusebenzeni nasekubambeleleni kodaka. Igama elithi “adhesion” lapha libhekisela emandleni okunamathela azwakala phakathi kwethuluzi lokufaka isicelo lesisebenzi kanye ne-substrate yodonga, okungukuthi, ukumelana ne-shear kodaka. I-adhesiveness iphakeme, ukumelana kwe-shear kodaka kukhulu, futhi amandla adingwa ngabasebenzi ngesikhathi sokusebenzisa nawo makhulu, futhi ukusebenza kokwakhiwa kodaka kumpofu. I-Methyl cellulose adhesion isezingeni elilinganiselwe emikhiqizweni ye-cellulose ether.
(3) Ukugcinwa kwamanzi kwe-hydroxypropyl methylcellulose kuncike enanini layo elingeziwe, i-viscosity, njll., futhi izinga layo lokugcinwa kwamanzi ngaphansi kwenani elifanayo lokwengezwa lingaphezulu kwele-methyl cellulose.
Ukugcinwa kwamanzi kwe-methylcellulose kuncike enanini layo elingeziwe, i-viscosity, ukucoleka kwezinhlayiyana nezinga lokuqedwa. Ngokuvamile, uma inani elingeziwe likhulu, ukucoleka kuncane, futhi i-viscosity inkulu, izinga lokugcinwa kwamanzi liphezulu. Phakathi kwazo, inani lokwengeza linomthelela omkhulu kakhulu ekugcinweni kwamanzi, futhi izinga le-viscosity alilingani ngokuqondile nezinga lokugcinwa kwamanzi. Izinga lokuhlakazeka lincike kakhulu ezingeni lokuguqulwa kwendawo yezinhlayiya ze-cellulose kanye nokucoleka kwezinhlayiyana. Phakathi kwama-cellulose ether angenhla, i-methyl cellulose ne-hydroxypropyl methyl cellulose anamazinga aphezulu okugcina amanzi.
(4) I-Hydroxypropyl methylcellulose ingaxutshwa nezinhlanganisela ze-polymer ezincibilika emanzini ukuze zenze isisombululo esifanayo nesiphezulu se-viscosity. Okufana ne-polyvinyl alcohol, isitashi ether, i-vegetable gum, njll. Ukunamathela kwe-hydroxypropyl methylcellulose ekwakhiweni kodaka kuphezulu kunokwe-methylcellulose.
I-Hydroxypropyl methylcellulose inokumelana ne-enzyme okungcono kune-methylcellulose, futhi isisombululo sayo mancane amathuba okuthi sonakaliswe ama-enzyme kune-methylcellulose.
Ukushintsha kwezinga lokushisa kungathinta kakhulu ukugcinwa kwamanzi kwe-methyl cellulose. Ngokuvamile, lapho izinga lokushisa liphezulu, kuba kubi nakakhulu ukugcinwa kwamanzi. Uma izinga lokushisa lodaka lidlula i-40 ° C, ukugcinwa kwamanzi kwe-methyl cellulose kuzoncishiswa kakhulu, okuthinta kakhulu ukwakhiwa kodaka. Uma izinga lokushisa liphezulu uma kuqhathaniswa, zama ukukhetha i-hydroxypropyl methylcellulose.
Isikhathi sokuthumela: Dec-20-2022