A:
I-MC i-methyl cellulose: ukotini ocolisisiwe ngemva kokwelashwa kwe-alkali, i-methane chloride njenge-ejenti e-etherifying, ngochungechunge lokusabela ukwenza i-cellulose ether. Ngokuvamile, izinga lokushintsha lingu-1.6~2.0, futhi ukuncibilika kuyahlukahluka ngezinga lokushintsha. Ingeka-nonionic cellulose ether.
(1) Ukugcinwa kwamanzi kwe-methyl cellulose kuncike enanini layo elingeziwe, i-viscosity, ukucoleka kwezinhlayiyana nezinga lokuqedwa. Ngokuvamile engeza inani elikhulu, inhlawulo encane, i-viscosity, izinga lokugcinwa kwamanzi liphezulu. Inani lezithasiselo linethonya elikhulu kuzinga lokugcinwa kwamanzi, futhi i-viscosity ayilingani nezinga lokugcinwa kwamanzi. Izinga lokuncibilika lincike kakhulu kwidigri yokuguqulwa kwendawo kanye nokucoleka kwezinhlayiyana zezinhlayiya ze-cellulose. Kula ma-ether amaningi e-cellulose angenhla, i-methyl cellulose ne-HPMC hydroxypropyl methyl cellulose izinga lokugcinwa kwamanzi liphezulu.
(2) I-methyl cellulose iyancibilika emanzini abandayo, okunzima ukuyincibilika emanzini ashisayo. Isixazululo saso esinamanzi sizinzile kakhulu ngaphakathi kwe-pH=3~12. Inokuhambisana okuhle nesitashi, i-guanidine gum kanye nama-surfactants amaningi. I-Gelation kwenzeka lapho izinga lokushisa lifinyelela izinga lokushisa le-gelation.
(3) Ukushintsha kwezinga lokushisa kuzothinta kakhulu izinga lokugcinwa kwamanzi e-methyl cellulose. Ngokuvamile, lapho izinga lokushisa liphezulu, kuba kubi nakakhulu ukugcinwa kwamanzi. Uma izinga lokushisa lodaka lidlula ama-40℃, ukugcinwa kwamanzi kwe-methyl cellulose kuzoba kubi kakhulu, okuthinta kakhulu ukwakhiwa kodaka.
(4) I-Methyl cellulose inethonya elisobala ekwakhiweni nasekubambeleleni kodaka. "Ukunamathela" lapha kubhekisela ekunamatheleni okuzwiwa yisisebenzi phakathi kwethuluzi ne-substrate yodonga, okungukuthi ukumelana kwe-shear kodaka. Ukunamathela kukhulu, ukumelana kwe-shear kodaka kukhulu, amandla adingwa abasebenzi ngesikhathi sokusebenzisa nawo makhulu, futhi ukwakhiwa kodaka kumpofu. Emikhiqizweni ye-cellulose ether, ukunamathela kwe-methyl cellulose kusezingeni elilinganiselwe.
I-HPMC iyi-hydroxypropyl methyl cellulose: yenziwe ngokotini ocolisisiwe ngemva kokwelashwa kwe-alkali, nge-propylene oxide ne-chloromethane njenge-ejenti ye-etherifying, ngochungechunge lokusabela futhi yenziwe nge-non-ionic cellulose exutshwe i-ether. Izinga lokushintsha ngokuvamile liyi-1.2 ~ 2.0. Izakhiwo zayo ziyahlukahluka ngengxenye yokuqukethwe kwe-methoxy ne-hydroxypropyl.
(1) I-HPMC hydroxypropyl methyl cellulose inyibilika kalula emanzini abandayo, okunzima ukuyincibilikisa emanzini ashisayo. Kodwa-ke, izinga lokushisa layo le-gelation emanzini ashisayo ngokusobala liphakeme kunalelo le-methyl cellulose. Ukuncibilika kwe-methyl cellulose emanzini abandayo nakho kwathuthukiswa kakhulu.
(2) I-viscosity ye-HPMC hydroxypropyl methyl cellulose ihlobene nesisindo sayo samangqamuzana, futhi ukuphakama kwesisindo samangqamuzana, i-viscosity iphakama. Izinga lokushisa liphinde lithinte i-viscosity. I-viscosity iyancipha njengoba izinga lokushisa likhuphuka. Kodwa umphumela wayo wokushisa we-viscosity ophezulu uphansi kunalowo we-methyl cellulose. Isixazululo sizinzile uma sigcinwe ekamelweni lokushisa.
(3) I-HPMC hydroxypropyl methyl cellulose izinzile ku-asidi nesisekelo, futhi isisombululo sayo esinamanzi sizinzile kakhulu kububanzi be-pH=2~12. I-Caustic soda namanzi e-lime anethonya elincane ezindaweni zawo, kodwa i-alkali ingasheshisa izinga lokuqedwa futhi ithuthukise i-viscosity. I-HPMC hydroxypropyl methyl cellulose izinzile kusawoti ojwayelekile, kodwa lapho ukuhlangana kwesixazululo sikasawoti kuphezulu, i-viscosity ye-HPMC hydroxypropyl methyl cellulose imvamisa ukwanda.
(4) Ukugcinwa kwamanzi kwe-HPMC hydroxypropyl methyl cellulose kuncike esilinganisweni sayo kanye ne-viscosity, futhi izinga lokugcinwa kwamanzi le-HPMC hydroxypropyl methyl cellulose lingaphezulu kwele-methyl cellulose ngesikali esifanayo.
(5) I-HPMC i-hydroxypropyl methyl cellulose ingaxutshwa nezinhlanganisela ze-polymer ezincibilika emanzini ukuze zibe isixazululo esifanayo, se-viscosity ephakeme. Okufana ne-polyvinyl alcohol, isitashi ether, iglue yemifino nokunye.
(6) Ukunamathela kwe-HPMC hydroxypropyl methyl cellulose ekwakhiweni kodaka kungaphezulu kwalokho kwe-methyl cellulose.
(7) I-HPMC hydroxypropyl methyl cellulose inokumelana ne-enzyme engcono kune-methyl cellulose, futhi amathuba ayo okuwohloka kwe-enzyme yesisombululo aphansi kunalawo e-methyl cellulose.
Isikhathi sokuthumela: May-26-2022