1. Hydroxypropyl methyl cellulose
Hydroxypropyl methylcelluloseke mofuta oa cellulose oo tlhahiso le tšebeliso ea oona li ntseng li eketseha ka potlako. Ke ether e tsoakiloeng ea cellulose e seng ea ionic e entsoeng ka k'hothone e hloekisitsoeng ka mor'a alkalization, e sebelisang propylene oxide le methyl chloride e le moemeli oa etherification, ka letoto la liketso. Tekanyo ea ho nkeloa sebaka ka kakaretso ke 1.2 ~ 2.0. Thepa ea eona e fapana ho latela karolelano ea litaba tsa methoxyl ho litaba tsa hydroxypropyl.
(1) Hydroxypropyl methylcellulose e qhibiliha habonolo metsing a batang, 'me e tla tobana le mathata ha e qhibiliha ka metsing a chesang. Empa mocheso oa eona oa gelation metsing a chesang o phahame haholo ho feta oa methyl cellulose. Ho qhibiliha ha eona metsing a batang le hona ho ntlafetse haholo ha ho bapisoa le methyl cellulose.
(2) (2) Ho teteana ha hydroxypropyl methylcellulose ho amana le boima ba eona ba limolek'hule, 'me ha boima ba limolek'hule bo le boholo, ho teteana ho ba holimo. Mocheso le oona o ama ho teteana ha eona, ha mocheso o ntse o eketseha, ho teteana hoa fokotseha. Leha ho le joalo, tšusumetso ea ho teteana ha eona ho phahameng le mocheso e tlase ho feta ea methyl cellulose. Tharollo ea eona e tsitsitse ha e bolokoa mochesong oa kamore.
(3) Ho boloka metsi ha hydroxypropyl methylcellulose ho itshetlehile ka bongata ba yona ba ho eketsa, viscosity, jj., mme sekgahla sa yona sa ho boloka metsi tlasa bongata bo lekanang ba ho eketsa se hodimo ho feta sa methyl cellulose.
(4) Hydroxypropyl methylcellulose e tsitsitse ho ea ho asiti le alkali, 'me tharollo ea eona ea metsi e tsitsitse haholo ho ea ho pH=2~12. Caustic soda le metsi a lime ha li na tšusumetso e kholo ts'ebetsong ea eona, empa alkali e ka potlakisa sekhahla sa ho qhibiliha ha eona le ho eketsa viscosity ea eona hanyane. Hydroxypropyl methylcellulose e tsitsitse ho ea ho letsoai le tloaelehileng, empa ha mahloriso a tharollo ea letsoai a le holimo, viscosity ea tharollo ea hydroxypropyl methylcellulose e atisa ho eketseha.
(5) Hydroxypropyl methylcellulose e ka kopanngoa le li-polymer tse qhibilihang ka metsing ho etsa tharollo e ts'oanang, e nang le viscosity e phahameng. Tse kang polyvinyl alcohol, starch ether, vegetable gum, jj.
(6) Hydroxypropyl methylcellulose e na le khanyetso e betere ea lienzyme ho feta methylcellulose, 'me tharollo ea eona ha e na monyetla oa ho senyeha ke lienzyme ho feta methylcellulose.
(7) Ho khomarela ha hydroxypropyl methylcellulose kahong ea seretse ho phahame ho feta ha methylcellulose.
2. Hydroxyethyl cellulose
E entsoe ka k'hothone e hloekisitsoeng e phekotsoeng ka alkali, 'me e arajoa ka ethylene oxide e le moemeli oa etherification ha ho na le isopropanol. Tekanyo ea eona ea ho nkeloa sebaka hangata ke 1.5 ~ 2.0. E na le philicity e matla ea hydrophilicity 'me e bonolo ho monya mongobo.
(1) Hydroxyethyl cellulose e qhibiliha metsing a batang, empa ho thata ho e qhibilihisa metsing a chesang. Tharollo ea eona e tsitsitse mochesong o phahameng ntle le ho e kenya ka gelling. E ka sebelisoa nako e telele tlas'a mocheso o phahameng ka har'a seretse, empa ho boloka metsi ha eona ho tlase ho feta ha methyl cellulose.
(2)Hydroxyethyl cellulosee tsitsitse ho acid le alkali ka kakaretso, 'me alkali e ka potlakisa ho qhibiliha ha eona le ho eketsa viscosity ea eona hanyane. Ho qhalana ha eona metsing ho mpe hanyane ho feta ha methyl cellulose le hydroxypropyl methyl cellulose.
(3) Hydroxyethyl cellulose e na le ts'ebetso e ntle ea ho thibela ho oa ha seretse, empa e na le nako e telele ea ho lieha bakeng sa samente.
(4) Tshebetso ya hydroxyethyl cellulose e hlahiswang ke dikgwebo tse ding tsa malapeng e totobetse hore e tlase ho feta ya methyl cellulose ka lebaka la metsi a mangata le molora o mongata.
(5) Mongobo wa tharollo ya metsi ya hydroxyethyl cellulose o kotsi haholo. Mochesong wa hoo e ka bang 40°C, mongobo o ka hlaha matsatsing a 3 ho isa ho a 5, e leng se tla ama tshebetso ya wona.
Nako ea poso: Mmesa-28-2024