Methyl Cellulose (MC) Foromo ea molek'hule \[C6H7O2(OH)3-h(OCH3)n1] x K'hothone e hloekisitsoeng e tšoaroa ka alkali,' me methyl chloride e sebelisoa e le etherification agent. Ka mor'a letoto la liketso, phekolo ea cellulose ether e etsoa. Ka kakaretso, tekanyo ea ho nka sebaka ke 1.6 ~ 2.0, 'me tekanyo ea ho fetola e fapane. Ke ea non-ionic cellulose ether.
1. Methylcellulose e qhibiliha ka metsing a batang, metsi a chesang a tla kopana le mathata, 'me sebaka sa pH sa tharollo ea metsi se tsitsitse haholo pakeng tsa 3/12. Starch, guar gum le li-surfactants tse ling tse ngata li lumellana haholoanyane. Gelation e etsahala ha mocheso o fihla mocheso oa gelation.
Ho boloka metsi a methylcellulose ho itšetlehile ka palo ea eona e eketsehileng, viscosity, fineness ea likaroloana le sekhahla sa ho qhibiliha. Ka kakaretso e atolosoa, e nyenyane, viscosity e phahameng, ho boloka metsi a mangata. Har'a bona, ho boloka metsi ho na le tšusumetso e kholo ka ho fetisisa, 'me boemo ba viscosity ha bo lekane ka ho toba le ho boloka metsi. Sekhahla sa ho qhibiliha haholo-holo se itšetlehile ka tekanyo ea phetoho ea bokaholimo ba likaroloana tsa cellulose le botle ba likaroloana. Har'a li-ether tsa cellulose tse ka holimo, methyl cellulose le hydroxypropyl methyl cellulose li na le ho boloka metsi a mangata.
Liphetoho tsa mocheso li ka ama haholo ho bolokoa ha metsi a methyl cellulose. - Ha mocheso o phahame, ho mpefala ha metsi ho boloka metsi. Haeba mocheso oa seretse o feta 40 ° C, ho boloka metsi a methyl cellulose ho tla fokotseha haholo, ho ama ka ho teba ho hahoa ha seretse.
Methylcellulose e na le phello e kholo ho sebetsa le ho khomarela seretse. "Ho khomarela" mona ho bolela ho khomarela pakeng tsa sesebelisoa sa mosebetsi le karoloana ea lebota, ke hore, ho hanyetsa ha seretse sa seretse. Viscosity, matla a ho kuta seretse, le matla a hlokoang ke basebetsi ba sebelisoang le tsona li kholo haholo, 'me kaho ea seretse ha e ntle. Methylcellulose e khomaretse maemo a itekanetseng lihlahisoa tsa cellulose ether.
2. Hydroxypropyl methylcellulose (HPMC) [C 6 H 7 O 2 (OH) 3-mn (OCH 3 ) m, OCH 2 CH (OH) CH 3 ] n] hydroxypropyl methyl cellulose Lilemong tsa morao tjena, mefuta ea cellulose e na le e ile ea eketseha ka potlako. Ke cellulose e se nang ionic e tsoakiloeng e lokisitsoeng ke letoto la liketso ka mor'a alkalization ea k'hothone e hloekisitsoeng alkali, moo propylene oxide le methyl chloride li sebelisoang e le li-etherification agents. Tekanyo ea ho fetola hangata ke 1.2/2.0. Thepa ea eona e fapana ho ea ka karo-karolelano ea methoxyl content le hydroxypropyl content.
1. Hydroxypropyl methylcellulose e arotsoe ka mofuta oa hot-melt le mofuta oa hang-hang. Mocheso oa eona oa gelation metsing a chesang o phahame haholo ho feta oa methylcellulose. E boetse e bontša ntlafatso e kholo ho feta methylcellulose ha e qhibiliha metsing a batang.
The viscosity ea hydroxypropyl methylcellulose e amana le boima ba molek'hule, 'me boima ba molek'hule bo phahame. Mocheso o boetse o ama viscosity ea eona, ha mocheso o ntse o eketseha, viscosity e fokotseha. Leha ho le joalo, tšusumetso ea mocheso ho viscosity e tlase ho feta ea methyl cellulose. Tharollo ke mokhoa o tsitsitseng oa ho boloka mocheso oa kamore.
3. Ho boloka metsi a hydroxypropyl methylcellulose ho itšetlehile ka palo ea eona ea ho eketsa, viscosity, joalo-joalo, 'me tekanyo ea ho boloka metsi e lekanang le eona e phahametse ea methyl cellulose.
4. Hydroxypropyl methylcellulose e tsitsitse ho acid le alkali, 'me tharollo ea eona ea metsi e tsitsitse haholo ka pH ea 2/12. Ts'ebetso ea caustic soda le metsi a lime ha e na tšusumetso e ngata, empa alkali e ka potlakisa sekhahla sa ho qhibiliha, 'me viscosity ea eketseha. Hydroxypropyl methylcellulose e tsitsitse ho matsoai a tloaelehileng, empa ha motsoako oa motsoako oa letsoai o phahame, viscosity ea tharollo ea hydroxypropyl methylcellulose e atisa ho eketseha.
Hydroxypropyl methylcellulose e ka tsoakoa le li-polymers tse qhibilihang ka metsing ho etsa tharollo e tšoanang, e nang le viscosity e phahameng. Joalo ka joala ba polyvinyl, starch ether, boka ba meroho, joalo-joalo.
Hydroxypropyl methylcellulose e na le khanyetso e ntle ea enzyme ho feta methylcellulose, monyetla oa ho senyeha ha enzymatic ea tharollo ea eona e tlase ho feta ea methylcellulose, 'me ho khomarela ha hydroxypropylmethylcellulose mohahong oa seretse ho phahame ho feta methylcellulose. cellulose ea motheo.
Tse tharo, hydroxyethyl cellulose (HEC) e entsoe ka k'hothone e hloekisitsoeng e phekotsoeng ka alkali, boteng ba acetone, le ethylene oxide e le etherification agent. Tekanyo ea eona ea ho fetola hangata ke 1.5 / 2.0. E na le hydrophilicity e matla 'me e bonolo ho monya mongobo.
1. Hydroxyethyl cellulose e qhibiliha ka metsing a batang, empa ho thata ho qhibiliha metsing a chesang. Tharollo e tsitsitse mocheso o phahameng mme ha e na thepa ea gel. E ka sebelisoa nako e telele seretseng sa mocheso o phahameng, empa ho boloka metsi ho tlase ho feta methyl cellulose.
2. Hydroxyethyl cellulose e tsitsitse ho acid e akaretsang le alkali. Alkali e potlakisa ho qhibiliha ha eona, 'me viscosity ea eona e eketseha hanyenyane. Phatlalatso ea eona metsing e mpe hanyane ho feta ea methyl cellulose le hydroxypropyl methyl cellulose.
3. Hydroxyethyl cellulose e na le ts'ebetso e ntle ea ho thibela ho fanyeha holim'a seretse, empa ka nako e telele, hydroxyethyl cellulose e hlahisoang malapeng e na le ts'ebetso e tlaase haholo ho feta methyl cellulose ka lebaka la metsi a mangata a metsi le molora o phahameng.
4. Carboxymethyl cellulose (CMC) \ [C6H7O2 (OH) 2och2COONa] (cotton, joalo-joalo) ea fiber ea tlhaho e tšoaroa ka alkali, 'me sodium chloroacetate e sebelisoa e le etherification agent, ka mor'a letoto la phekolo ea karabelo, e etsoa ionic. cellulose ether. Tekanyo ea ho nka sebaka ka kakaretso ke 0.4/1.4, 'me tekanyo ea phetoho e na le tšusumetso e kholo mosebetsing.
Carboxymethyl cellulose e na le hygroscopicity e phahameng, 'me maemo a polokelo ka kakaretso a na le metsi a mangata.
2. Carboxymethyl cellulose aqueous solution ha e hlahise gel, viscosity e fokotseha ha mocheso o phahama, 'me viscosity e ke ke ea fetoloa ha mocheso o feta 50 ° C.
Ho tsitsa ha eona ho angoa haholo ke pH. Ka kakaretso e sebelisoa bakeng sa seretse sa gypsum, eseng bakeng sa seretse sa samente. Tabeng ea alkalinity e phahameng, e tla lahleheloa ke viscosity ea eona.
Palo ea eona ea metsi e tlase haholo ho feta ea methyl cellulose. Seretse sa Gypsum se na le phello e nyenyefatsang, e fokotsang matla. Empa theko ea carboxymethyl cellulose e tlase haholo ho feta ea methyl cellulose.
Nako ea poso: Jan-13-2023