Igama lesiShayina le-HPMC yi-hydroxypropyl methylcellulose. Ayiyona i-ionic futhi ivame ukusetshenziswa njenge-ejenti egcina amanzi odakeni oluxutshwe okomile. Kuyinto esetshenziswa kakhulu ukugcina amanzi odakeni.
Inqubo yokukhiqiza ye-HPMC iwumkhiqizo we-ether osuselwe ku-polysaccharide okhiqizwa yi-alkalization kanye ne-etherification yefayibha kakotini (yasekhaya). Ayinayo inkokhiso ngokwayo, ayiphenduli ngama-ion ashajiwe ku-gelling material, futhi inokusebenza okuzinzile. Intengo futhi iphansi kunezinye izinhlobo ze-cellulose ethers, ngakho-ke isetshenziswa kakhulu kudaka oluxutshwe okomile.
Umsebenzi we-hydroxypropyl methylcellulose: Ingajiya udaka olusanda kuxutshwa ukuze lube ne-viscosity ethile emanzi futhi ivimbele ukuhlukaniswa. (Ukuqina) Ukugcinwa kwamanzi kuyisici esibaluleke kakhulu, esiza ukugcina inani lamanzi amahhala odakeni, ukuze ngemva kokwakhiwa kodaka, izinto zikasimende zibe nesikhathi esengeziwe sokudonsa amanzi. (Ukugcinwa kwamanzi) Inezici zokungenisa umoya, ezingakwazi ukwethula amabhamuza afanayo kanye namabhamuza amahle ukuze kuthuthukiswe ukwakhiwa kodaka.
Ukuphakama kwe-viscosity ye-hydroxypropyl methylcellulose ether, kuba ngcono ukusebenza kokugcinwa kwamanzi. I-Viscosity iyipharamitha ebalulekile yokusebenza kwe-HPMC. Njengamanje, abakhiqizi abahlukene be-HPMC basebenzisa izindlela namathuluzi ahlukene ukukala i-viscosity ye-HPMC. Izindlela eziyinhloko yi-HaakeRotovisko, i-Hoppler, i-Ubbelohde ne-Brookfield.
Ngomkhiqizo ofanayo, imiphumela ye-viscosity elinganiswa ngezindlela ezahlukene ihluke kakhulu, futhi eminye inomehluko ophindwe kabili. Ngakho-ke, uma uqhathanisa i-viscosity, kufanele yenziwe phakathi kwezindlela zokuhlola ezifanayo, okuhlanganisa izinga lokushisa, i-rotor, njll. Ngokuphathelene nosayizi wezinhlayiyana, i-particle encane, ukugcinwa kwamanzi kangcono. Ngemva kokuba izinhlayiya ezinkulu ze-cellulose ether zihlangana namanzi, indawo engaphezulu iyancibilika ngokushesha futhi yakhe ijeli ukuze igoqe into ukuvimbela ama-molecule amanzi ukuthi angaqhubeki nokungena. Ngezinye izikhathi ayikwazi ukuhlakazwa ngokufanayo futhi incibilike ngisho nangemva kokunyakaziswa kwesikhathi eside, kwakheka ikhambi eliguqubele le-flocculent noma i-agglomeration. Kuthinta kakhulu ukugcinwa kwamanzi kwe-cellulose ether, futhi ukuncibilika kungenye yezici zokukhetha i-cellulose ether.
I-Fineness futhi iyinkomba yokusebenza ebalulekile ye-methyl cellulose ether. I-MC esetshenziselwa udaka lwempushana eyomile iyadingeka ukuthi ibe yimpushana, enokuqukethwe kwamanzi aphansi, kanti ukucoleka kudinga u-20% ~ 60% wesayizi wezinhlayiyana ukuba ube ngaphansi kuka-63um. Ukucoleka kuthinta ukunyibilika kwe-hydroxypropyl methylcellulose ether. I-coarse MC ivamise ukuba yi-granular, futhi kulula ukuyincibilika emanzini ngaphandle kwe-agglomeration, kodwa izinga lokuhlakazeka lihamba kancane, ngakho-ke alifanelekile ukusetshenziswa kudaka oluyimpushana.
Odakeni lwempushana eyomile, i-MC ihlakazeka phakathi kwezinto zikasimende njenge-aggregate, isigcwalisi esihle nosimende, futhi impushana enhle kuphela eyanele engagwema i-methyl cellulose ether agglomeration lapho ixutshwa namanzi. Lapho i-MC yengezwe ngamanzi ukuze ihlakaze ama-agglomerate, kunzima kakhulu ukuhlakazeka nokuhlakazeka. Ukucoleka kwe-MC akukona nje ukumosha, kodwa futhi kunciphisa amandla endawo odaka. Uma i-powder mortar enjalo eyomile isetshenziswa endaweni enkulu, ijubane lokuphulukisa le-powder eyomile yendawo lizoncishiswa kakhulu, futhi imifantu izovela ngenxa yezikhathi ezahlukene zokuphulukisa. Ngodaka olufuthwe ngokwakhiwa kwemishini, imfuneko yokucwenga iphakeme ngenxa yesikhathi esifushane sokuxuba. Ngokuvamile, ukuphakama kwe-viscosity, kuba ngcono umphumela wokugcina amanzi. Kodwa-ke, ukuphakama kwe-viscosity futhi ukuphakama kwesisindo samangqamuzana e-MC, ukwehla okuhambisanayo kokuncibilika kwawo kuzoba nomthelela omubi emandleni nokusebenza kokwakhiwa kodaka.
Ukuphakama kwe-viscosity, kusobala kakhulu umphumela wokuqina odongeni, kodwa awulingani ngokuqondile. Ukuphakama kwe-viscosity, i-viscous yodaka olumanzi luyoba ngaphezulu, okungukuthi, ngesikhathi sokwakhiwa, kubonakala njengokunamathela ku-scraper nokunamathela okuphezulu ku-substrate. Kodwa akusizi ukwandisa amandla esakhiwo sodaka olumanzi ngokwalo. Okusho ukuthi, ngesikhathi sokwakhiwa, ukusebenza kwe-anti-sag akubonakali. Ngokuphambene, i-viscosity ethile emaphakathi nephansi kodwa eshintshiwe ye-methyl cellulose ethers inokusebenza okuhle kakhulu ekuthuthukiseni amandla esakhiwo sodaka olumanzi.
Ukugcinwa kwamanzi kwe-HPMC nakho kuhlobene nezinga lokushisa elisetshenzisiwe, futhi ukugcinwa kwamanzi kwe-methyl cellulose ether kuncipha ngokunyuka kwezinga lokushisa. Kodwa-ke, ekusetshenzisweni kwezinto ezibonakalayo, udaka oluyimpushana olomile luvame ukusetshenziswa ezindaweni ezishisayo emazingeni okushisa aphezulu (angaphezu kwama-degrees angu-40) ezindaweni eziningi, njengokuphahlelwa kwe-putty yangaphandle ngaphansi kwelanga ehlobo, okuvame ukusheshisa Ukuphulukiswa kukasimende nokuqina kukasimende. udaka olomile lwempuphu. Ukwehla kwezinga lokugcinwa kwamanzi kuholela emuzweni osobala wokuthi kokubili ukusebenza nokumelana nokuqhekeka kuyathinteka, futhi kubaluleke kakhulu ukunciphisa umthelela wezici zokushisa ngaphansi kwalesi simo.
Mayelana nalokhu, izithasiselo ze-methyl hydroxyethyl cellulose ether njengamanje zibhekwa njengezihamba phambili ekuthuthukisweni kobuchwepheshe. Nakuba inani le-methyl hydroxyethyl cellulose linyusiwe (ifomula yasehlobo), ukusebenza kahle nokumelana nokuqhekeka akukakwazi ukuhlangabezana nezidingo zokusetshenziswa. Ngokuphathwa okuthile okukhethekile ku-MC, njengokwandisa izinga le-etherification, njll., umphumela wokugcina amanzi ungagcinwa ezingeni lokushisa eliphezulu, ukuze ukwazi ukunikeza ukusebenza okungcono ngaphansi kwezimo ezinzima.
Umthamo we-HPMC akufanele ube phezulu kakhulu, ngaphandle kwalokho uzokwandisa isidingo samanzi osimende, uzonamathela ku-trowel, futhi isikhathi sokumisa sizoba side kakhulu, okuzothinta ukwakhiwa. Imikhiqizo ehlukene yodaka isebenzisa i-HPMC enamaviscosity ahlukene, futhi ayisebenzisi i-HPMC ene-viscosity ephezulu ngokunganaki. Ngakho-ke, nakuba imikhiqizo ye-hydroxypropyl methylcellulose imihle, ishayelwa ihlombe uma isetshenziswe kahle. Ukukhetha i-HPMC efanele kuwumthwalo wemfanelo oyinhloko wabasebenzi baselabhorethri yebhizinisi. Njengamanje, abathengisi abaningi abangathembekile bahlanganisa i-HPMC, futhi ikhwalithi iphansi impela. Lapho kukhethwa i-cellulose ethile, ilabhorethri kufanele yenze umsebenzi omuhle ekuhloleni ukuze kuqinisekiswe ukuzinza komkhiqizo wodaka, futhi ungahaleli ukushibhile futhi ubangele ukulahlekelwa okungadingekile.
Isikhathi sokuthumela: Dec-16-2022