HPMC ke hydroxypropyl methylcellulose, e leng selulose e seng ionic e tsoakiloeng ka k'hothone e hloekisitsoeng ka mor'a alkalization, e sebelisa propylene oxide le methyl chloride e le li-etherification agents, le ka letoto la liketso. Tekanyo ea ho nka sebaka ka kakaretso ke 1.2 ~ 2.0. Thepa ea eona e fapane ka lebaka la likarohano tse fapaneng tsa litaba tsa methoxyl le litaba tsa hydroxypropyl.
MC ke methyl cellulose, e entsoeng kacellulose etherka ho phekola k'hothone e hloekisitsoeng ka alkali, ho sebelisa methane chloride e le etherification agent, le ho latela letoto la liketso. Ka kakaretso, tekanyo ea ho fetola ke 1.6 ~ 2.0, 'me solubility e boetse e fapane le likhato tse fapaneng tsa ho fetola. Ke ea non-ionic cellulose ether.
Papiso ea ts'ebetso lipakeng tsa tse peli:
(1) Hydroxypropyl methylcellulose e qhibiliha habonolo metsing a batang, 'me e tla kopana le mathata a ho qhibiliha metsing a chesang. Empa mocheso oa eona oa gelation metsing a chesang o phahame haholo ho feta oa methyl cellulose. Ho qhibiliha ha metsi a batang ho boetse ho ntlafala haholo ha ho bapisoa le methyl cellulose. Hydroxypropyl methylcellulose e tsitsitse ho acid le alkali, 'me tharollo ea eona ea metsi e tsitsitse haholo ka pH = 2 ~ 12. Caustic soda le metsi a lime ha li na phello e fokolang ts'ebetsong ea eona, empa alkali e ka potlakisa ho qhibiliha ha eona le ho eketsa viscosity ea eona. Hydroxypropyl methylcellulose e tsitsitse ho matsoai a tloaelehileng, empa ha motsoako oa motsoako oa letsoai o phahame, viscosity ea hydroxypropyl methylcellulose tharollo e atisa ho eketseha.
Methylcellulose e boetse e qhibiliha ka metsing a batang, 'me ho tla ba thata ho qhibiliha ka metsing a chesang. Tharollo ea eona ea metsi e tsitsitse haholo maemong a pH = 3 ~ 12. E na le tumellano e ntle le starch, guar gum, joalo-joalo le li-surfactants tse ngata. Ha mocheso o fihla mocheso oa gelation, gelation e etsahala.
(2) Viscosity ea hydroxypropyl methylcellulose e amana le boima ba eona ba molek'hule, 'me ha boima ba molek'hule bo le boholo, ho ba le viscosity e phahameng. Mocheso o boetse o ama viscosity ea eona, ha mocheso o ntse o eketseha, viscosity e fokotseha. Leha ho le joalo, viscosity ea eona e phahameng e na le phello e tlase ea mocheso ho feta methyl cellulose. Tharollo ea eona e tsitsitse ha e bolokiloe mocheso oa kamore.
Methylcellulose e na le phello e kholo ho sebetsa le ho khomarela seretse. "Ho khomarela" mona ho bolela matla a sekhomaretsi a utloahalang pakeng tsa sesebelisoa sa mosebetsi le karoloana ea lebota, ke hore, ho hanyetsa ha seretse. Sekhomaretsi se phahame, khanyetso ea ho kuta ea seretse e kholo, 'me matla a hlokoang ke basebetsi ha a ntse a sebelisoa le ona a maholo,' me ts'ebetso ea kaho ea seretse e futsanehile. Methyl cellulose adhesion e boemong bo itekanetseng lihlahisoa tsa cellulose ether.
(3) Ho bolokoa ha metsi a hydroxypropyl methylcellulose ho itšetlehile ka palo ea eona ea tlatsetso, viscosity, joalo-joalo, 'me sekhahla sa eona sa ho boloka metsi tlas'a chelete e tšoanang ea tlatsetso e phahame ho feta ea methyl cellulose.
Ho boloka metsi a methylcellulose ho ipapisitse le palo ea eona ea tlatsetso, viscosity, botle ba likaroloana le sekhahla sa ho qhibiliha. Ka kakaretso, haeba palo ea tlatsetso e le kholo, botle bo nyane, 'me viscosity e kholo, sekhahla sa ho boloka metsi se phahame. Har'a bona, palo ea ho eketsoa e na le tšusumetso e kholo ka ho fetisisa ho tekanyo ea ho boloka metsi, 'me boemo ba viscosity ha bo lekane ka ho toba le tekanyo ea 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 litekanyetso tse phahameng tsa ho boloka metsi.
(4) Hydroxypropyl methylcellulose e ka kopanngoa le metsoako ea polymer e qhibilihang ka metsing ho etsa tharollo e tšoanang le e phahameng ea viscosity. Tse kang joala ba polyvinyl, starch ether, gum ea meroho, joalo-joalo Ho khomarela ha hydroxypropyl methylcellulose mohahong oa seretse ho phahame ho feta methylcellulose.
Hydroxypropyl methylcellulose e na le khanyetso e ntle ea enzyme ho feta methylcellulose, 'me tharollo ea eona ha e na monyetla oa ho senngoa ke li-enzyme ho feta methylcellulose.
Liphetoho tsa mocheso li ka ama haholo ho boloka metsi a methyl cellulose. Ka kakaretso, ha thempereichara e 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. Ha mocheso o batla o phahame, leka ho khetha hydroxypropyl methylcellulose.
Nako ea poso: Dec-20-2022