Methylcellulose (MC) ke mofuta oa ether ea cellulose. Metsoako ea ether ea cellulose ke li-derivative tse fumanoang ka ho fetola cellulose ea tlhaho ka lik'hemik'hale, 'me methylcellulose ke setlolo sa bohlokoa sa cellulose se entsoeng ka methylating (methyl substitution) karolo ea hydroxyl ea cellulose. Ka hona, methylcellulose ha se feela setlolo sa cellulose, empa hape ke ether e tloaelehileng ea cellulose.
1. Tokiso ea methylcellulose
Methylcellulose e lokisoa ka ho kopanya cellulose le moemeli oa methylating (joalo ka methyl chloride kapa dimethyl sulfate) tlas'a maemo a alkaline ho kopanya karolo ea hydroxyl ea cellulose. Karabelo ena e etsahala haholo-holo lihlopheng tsa hydroxyl maemong a C2, C3 le C6 a cellulose ho theha methylcellulose ka maemo a fapaneng a ho nkeloa sebaka. Ts'ebetso ea karabelo e tjena:
Cellulose (polysaccharide e entsoeng ka diyuniti tsa glucose) e qala ho kenngwa tshebetsong tlasa maemo a alkaline;
Ebe moemeli oa methylating o hlahisoa ho etsa karabelo ea etherification ho fumana methylcellulose.
Mokhoa ona o ka hlahisa dihlahiswa tsa methylcellulose tse nang le dibopeho tse fapaneng tsa ho qhibilihisa le ho qhibiliha ka ho laola maemo a karabelo le tekanyo ya methylation.
2. Thepa ea methylcellulose
Methylcellulose e na le likarolo tse latelang tsa bohlokoa:
Ho qhibiliha: Ho fapana le cellulose ea tlhaho, methylcellulose e ka qhibiliha ka metsing a batang empa e seng ka metsing a chesang. Lebaka ke hobane ho kenngoa ha metsoako ea methyl ho senya litlamo tsa haedrojene pakeng tsa limolek'hule tsa cellulose, ka hona ho fokotsa kristale ea eona. Methylcellulose e etsa tharollo e bonaletsang ka metsing 'me e bontša litšobotsi tsa gelation mochesong o phahameng, ke hore, tharollo ea teteana ha e futhumatsoa 'me e fumana metsi hape ka mor'a ho pholile.
Ha e na chefo: Methylcellulose ha e na chefo 'me ha e monyehe ke tsamaiso ea tšilo ea lijo ea motho. Ka hona, hangata e sebelisoa lijong le meriana e le sethibela-mafu, se kopanyang le se tiisang.
Taolo ea ho teteana: Methylcellulose e na le litšobotsi tse ntle tsa taolo ea ho teteana, 'me ho teteana ha tharollo ea eona ho amana le mahloriso a tharollo le boima ba limolek'hule. Ka ho laola tekanyo ea ho nkeloa sebaka karabelong ea etherification, lihlahisoa tsa methylcellulose tse nang le mefuta e fapaneng ea ho teteana li ka fumanoa.
3. Tšebeliso ea methylcellulose
Ka lebaka la thepa ea eona e ikhethang ea 'mele le ea lik'hemik'hale, methylcellulose e sebelisitsoe haholo liindastering tse ngata.
3.1 Indasteri ea lijo
Methylcellulose ke sejo se tloaelehileng se sebelisoang lijong tse fapaneng tse sebelisoang ho lokisa lijo, haholo-holo e le sethibela-khatello, emulsifier le stabilizer. Kaha methylcellulose e ka hlapolla ha e futhumatsoa le ho khutlisa mokelikeli ka mor'a ho pholile, hangata e sebelisoa lijong tse hoamisitsoeng, lijong tse besitsoeng le sophong. Ho phaella moo, tlhaho ea methylcellulose ea lik'hilojule tse tlase e etsa hore e be motsoako oa bohlokoa mefuteng e meng ea lijo tse nang le lik'hilojule tse tlase.
3.2 Liindasteri tsa meriana le tsa bongaka
Methylcellulose e sebelisoa haholo indastering ea meriana, haholo-holo tlhahisong ea matlapa, e le sesebelisoa sa ho thusa le ho kopanya. Ka lebaka la bokhoni ba eona bo botle ba ho lokisa viscosity, e ka ntlafatsa matla a mechini le thepa ea ho qhibiliha ha matlapa ka katleho. Ho phaella moo, methylcellulose e boetse e sebelisoa e le karolo ea ho taboha ha maiketsetso ho tsa mahlo ho phekola mahlo a omileng.
3.3 Indasteri ea kaho le thepa
Har'a thepa ea kaho, methylcellulose e sebelisoa haholo ka samente, gypsum, liphahlo le likhomaretsi e le setenya, se bolokang metsi le se etsang filimi. Ka lebaka la ho boloka metsi hantle, methylcellulose e ka ntlafatsa ho phalla le ho sebetsa ha thepa ea kaho le ho qoba ho hlaha ha mapetso le likheo.
3.4 Indasteri ea litlolo
Methylcellulose e boetse e sebelisoa haholo indastering ea litlolo e le setei le se tiisang ho thusa ho theha li-emulsion le li-gel tse tšoarellang nako e telele. E ka ntlafatsa maikutlo a sehlahisoa le ho ntlafatsa phello ea mongobo. Ha e bake allergy ebile e bonolo, 'me e loketse letlalo le bonolo.
4. Papiso ea methylcellulose le li-ether tse ling tsa cellulose
Li-ether tsa cellulose ke lelapa le leholo. Ntle le methylcellulose, ho boetse ho na le ethyl cellulose (EC), hydroxypropyl methylcellulose (HPMC), hydroxyethyl cellulose (HEC) le mefuta e meng. Phapang ea tsona e kholo e ho mofuta le tekanyo ea ho nkeloa sebaka ha lintho tse nkeloang sebaka molek'huleng ea cellulose, e leng se etsang qeto ea ho qhibiliha ha tsona, ho teteana ha tsona le libaka tsa ts'ebeliso.
Methylcellulose vs Hydroxypropyl Methylcellulose (HPMC): HPMC ke mofuta o ntlafetseng wa methylcellulose. Ntle le methyl substituent, hydroxypropyl le yona e a hlahiswa, e leng se etsang hore ho qhibiliha ha HPMC ho fapane haholo. HPMC e ka qhibilihisoa ka mocheso o pharaletseng, mme mocheso wa yona wa gelation o phahame ho feta wa methylcellulose. Ka hona, diindastering tsa thepa ya kaho le meriana, HPMC e na le mefuta e mengata ya ditshebediso.
Methylcellulose khahlanong le Ethyl Cellulose (EC): Ethyl cellulose ha e qhibilihe ka metsing, empa e qhibiliha ka har'a metsoako ea lintho tse phelang. Hangata e sebelisoa ka har'a thepa ea lera e lokollang nako e telele bakeng sa ho koahela le lithethefatsi. Methyl cellulose e qhibiliha ka har'a metsi a batang 'me e sebelisoa haholo-holo e le ntho e tenya le e bolokang metsi. Libaka tsa ts'ebeliso ea eona li fapane le tsa ethyl cellulose.
5. Mokhoa oa nts'etsopele ea li-ether tsa cellulose
Ka tlhoko e ntseng e eketseha ea thepa e tsitsitseng le lik'hemik'hale tse tala, metsoako ea ether ea cellulose, ho kenyeletsoa le methyl cellulose, butle-butle e fetoha karolo ea bohlokoa ea thepa e sireletsang tikoloho. E nkiloe likhoeleng tsa limela tsa tlhaho, e ka nchafatsoa, 'me e ka senyeha ka tlhaho tikolohong. Nakong e tlang, libaka tsa ts'ebeliso ea li-ether tsa cellulose li ka atolosoa haholoanyane, joalo ka matla a macha, mehahong e tala le biomedicine.
Jwalo ka mofuta wa ether ya cellulose, methyl cellulose e sebediswa haholo diindastering tse ngata ka lebaka la thepa ya yona e ikgethang ya mmele le ya dikhemikhale. Ha e na feela bokgoni bo botle ba ho qhibiliha, ho se be le chefo, le ho fetola viscosity hantle, empa hape e bapala karolo ya bohlokwa dijong, merianeng, kahong le ditlolong. Nakong e tlang, ka lebaka la tlhoko e ntseng e eketseha ya thepa e sireletsang tikoloho, menyetla ya tshebediso ya methyl cellulose e tla ba kgolo.
Nako ea poso: Mphalane-23-2024