Hydroxypropyl methylcelluloseke mofuta oa ether e tsoakiloeng ea cellulose e seng ea ionic. Ho fapana le ether e tsoakiloeng ea ionic methyl carboxymethyl cellulose, ha e arabele le litšepe tse boima. Ka lebaka la likarohano tse fapaneng tsa methoxyl le hydroxypropyl ka har'a hydroxypropyl methylcellulose le viscosities tse fapaneng, ho na le mefuta e mengata e nang le thepa e fapaneng, mohlala, dikahare tse phahameng tsa methoxyl le dikahare tse tlase tsa hydroxypropyl Tshebetso ea eona e haufi le ea methyl cellulose, ha ts'ebetso ea dikahare tse tlase tsa methoxyl le dikahare tse phahameng tsa hydroxypropyl e haufi le ea hydroxypropyl methyl cellulose. Leha ho le joalo, mofuteng o mong le o mong, leha ho na le karolo e nyane feela ea sehlopha sa hydroxypropyl kapa sehlopha se senyenyane sa methoxyl, ho na le liphapang tse kholo ho qhibiliheng ha lintho tse phelang kapa mocheso oa flocculation litharollong tsa metsi.
(1) Thepa ea ho qhibiliha ha hydroxypropyl methylcellulose
① Ho qhibiliha ha hydroxypropyl methylcellulose ka metsingHydroxypropyl methylcelluloseHa e le hantle ke mofuta oa methylcellulose e fetotsoeng ke propylene oxide (methoxy-propylene), kahoo e ntse e na le thepa e tšoanang le ea methyl cellulose e na le litšobotsi tse tšoanang tsa ho qhibiliha ha metsi a batang le ho se qhibilihe ha metsi a chesang. Leha ho le joalo, ka lebaka la sehlopha sa hydroxypropyl se fetotsoeng, mocheso oa eona oa gelation metsing a chesang o phahame haholo ho feta oa methyl cellulose. Mohlala, viscosity ea tharollo ea metsi ea hydroxypropyl methylcellulose e nang le tekanyo ea 2% ea methoxy content substitution DS=0.73 le hydroxypropyl content MS=0.46 ke 500 mpa·s ho 20°C, 'me mocheso oa eona oa gel E ka fihla haufi le 100°C, ha methyl cellulose mochesong o tšoanang e le hoo e ka bang 55°C feela. Ha e le ho qhibiliha ha eona metsing, e boetse e ntlafalitsoe haholo. Mohlala, hydroxypropyl methylcellulose e silafalitsoeng (sebopeho sa granular 0.2 ~ 0.5mm ho 20°C ka viscosity ea tharollo ea metsi ea 4% ea 2pa•s e ka rekoa mochesong oa kamore, e qhibiliha habonolo metsing ntle le ho pholisa.
② Ho qhibiliha ha hydroxypropyl methylcellulose ka har'a metsoako ea lintho tse phelang ho qhibiliha ha hydroxypropyl methylcellulose ka har'a metsoako ea lintho tse phelang ho molemo ho feta ha methylcellulose. Methylcellulose e hloka ho ba le tekanyo ea phetolo ea methoxyl ea 2.1 Lihlahisoa tse boletsoeng ka holimo, empa li na le hydroxypropyl MS=1.5~1.8 le methoxy DS=0.2~1.0, hydroxypropyl methylcellulose e nang le viscosity e phahameng e nang le tekanyo e felletseng ea phetolo e kaholimo ho 1.8 e qhibiliha ka har'a litharollo tsa methanol le ethanol tse sa keneleng metsi, 'me e na le thermos-plasticity le ho qhibiliha ha metsi. E boetse e qhibiliha ka har'a li-hydrocarbon tse nang le chlorine tse kang methylene chloride le chloroform, le metsoako ea lintho tse phelang e kang acetone, isopropanol le diacetone alcohol. Ho qhibiliha ha eona ka har'a metsoako ea lintho tse phelang ho molemo ho feta ho qhibiliha ha metsi.
(2) Mabaka a Susumetsang Viscosity ea Hydroxypropyl Methyl Cellulose Tekanyetso e tloaelehileng ea viscosity ea hydroxypropyl methyl cellulose e tšoana le ea li-ether tse ling tsa cellulose. E lekanngoa ho 20°C ka tharollo ea metsi ea 2% joalo ka tekanyetso. Viscosity ea sehlahisoa se le seng e eketseha ka keketseho ea mahloriso. Bakeng sa lihlahisoa tse nang le boima bo fapaneng ba limolek'hule ka mahloriso a tšoanang, sehlahisoa se nang le boima bo boholo ba limolek'hule se na le viscosity e phahameng. Kamano ea sona le mocheso e tšoana le ea methyl cellulose. Ha mocheso o phahama, viscosity e qala ho theoha, empa ha e fihla mochesong o itseng, viscosity e phahama ka tšohanyetso 'me gelation ea etsahala. Mocheso oa gel oa lihlahisoa tse nang le viscosity e tlase o phahame. Ntlha ea eona ea gel ha e amane feela le viscosity ea ether, empa hape e amana le karolelano ea sebopeho sa sehlopha sa methoxyl le sehlopha sa hydroxypropyl ho ether le boholo ba tekanyo eohle ea phetolo. Ho lokela ho hlokomeloa hore hydroxypropyl methylcellulose le eona ke pseudoplastic, 'me tharollo ea eona e tsitsitse mochesong oa kamore ntle le ho senyeha ha viscosity ntle le monyetla oa ho senyeha ha enzymatic.
(3) Mamello ea letsoai ea hydroxypropyl methylcellulose Kaha hydroxypropyl methylcellulose ke ether e seng ea ionic, ha e ionized metsing a metsi, ho fapana le li-ether tse ling tsa ionic cellulose, tse kang carboxymethyl Base cellulose, tharollong ea ho arabela ka li-ion tsa tšepe e boima le precipitate. Matsoai a akaretsang a kang chloride, bromide, phosphate, nitrate, jj. a ke ke a potlaka ha a eketsoa tharollong ea eona ea metsi. Leha ho le joalo, ho eketsoa ha letsoai ho na le tšusumetso e itseng mochesong oa flocculation oa tharollo ea eona ea metsi. Ha khatello ea letsoai e eketseha, mocheso oa gel oa fokotseha. Ha khatello ea letsoai e le ka tlase ho ntlha ea flocculation, viscosity ea tharollo e atisa ho eketseha. Ka hona, tekanyo e itseng ea letsoai ea eketsoa, ha e sebelisoa, e ka fihlela phello ea ho teteana ka mokhoa o itekanetseng. Ka hona, lits'ebetsong tse ling, ho molemo ho sebelisa motsoako oa ether ea cellulose le letsoai ho feta khatello e phahameng ea tharollo ea ether ho fihlela phello ea ho teteana.
(4) Hydroxypropyl methylcellulose acid le khanyetso ea alkali Hydroxypropyl methylcellulose ka kakaretso e tsitsitse ho li-acid le li-alkali, 'me ha e amehe ka har'a pH 2 ~ 12. E ka mamella bongata bo itseng ba asiti e bobebe, joalo ka formic acid, acetic acid, citric acid, succinic acid, phosphoric acid, boric acid, jj. Empa asiti e kopaneng e na le phello ea ho fokotsa viscosity. Li-alkali tse kang caustic soda, caustic potash le metsi a lime ha li na phello ho eona, empa li ka eketsa viscosity ea tharollo hanyane, ebe lia e fokotsa butle-butle.
(5) Ho kopana ha hydroxypropyl methylcellulose Tharollo ea hydroxypropyl methylcellulose e ka kopanngoa le metsoako ea polymer e qhibilihang ka metsing hore e be tharollo e tšoanang le e bonaletsang e nang le viscosity e phahameng. Metsoako ena ea polymer e kenyelletsa polyethylene glycol, polyvinyl acetate, polysilicone, polymethylvinyl siloxane, hydroxyethyl cellulose, le methyl cellulose. Metsoako ea tlhaho e nang le limolek'hule tse ngata joalo ka gum arabic, locust bean gum, karaya gum, jj. le eona e na le tšebelisano e ntle le tharollo ea eona. Hydroxypropyl methylcellulose e ka boela ea kopanngoa le mannitol ester kapa sorbitol ester ea stearic acid kapa palmitic acid, 'me e ka boela ea kopanngoa le glycerin, sorbitol le mannitol, 'me metsoako ena e ka sebelisoa e le hydroxypropyl methylcellulose Plasticizer bakeng sa cellulose.
(6) E sa qhibiliheng ka metsingli-ether tsa seluloseea hydroxypropyl methylcellulose e ka etsa ho hokahanya holim'a metsi le aldehydes, e le hore li-ether tsena tse qhibilihang ka metsing li kenngoe ka har'a tharollo 'me li se ke tsa qhibiliha ka metsing. Li-aldehyde tse etsang hore hydroxypropyl methylcellulose e se ke ea qhibiliha li kenyelletsa formaldehyde, glyoxal, succinic aldehyde, adipaldehyde, jj. Ha ho sebelisoa formaldehyde, tlhokomelo e khethehileng e lokela ho lefshoa boleng ba pH ba tharollo, eo har'a eona glyoxal e arabelang ka potlako, kahoo glyoxal e sebelisoa hangata e le moemeli oa ho hokahanya tlhahiso ea indasteri. Tekanyo ea mofuta ona oa moemeli oa ho hokahanya ka har'a tharollo ke 0.2% ~ 10% ea boima ba ether, haholo-holo 7% ~ 10%, mohlala, 3.3% ~ 6% ea glyoxal ke eona e loketseng ka ho fetisisa. Ka kakaretso, mocheso oa phekolo ke 0 ~ 30℃, 'me nako ke 1 ~ 120min. Karabelo ea ho hokahanya e hloka ho etsoa tlas'a maemo a asiti. Ka kakaretso, pH ea tharollo e fetoloa ho ba hoo e ka bang 2~6 ka ho eketsa asiti e matla e sa tloaelehang kapa asiti ea carboxylic ea organic tharollong, haholo-holo pakeng tsa 4~6, ebe ho eketsoa li-aldehydes ho etsa karabelo ea ho kopanya. Asiti e sebelisitsoeng e na le asiti ea hydrochloric, asiti ea sulfuric, asiti ea phosphoric, asiti ea formic, asiti ea acetic, asiti ea hydroxy-acetic, asiti ea succinic kapa asiti ea citric jj., moo ho eletsoang hore ho sebelisoe asiti ea formic kapa asiti ea acetic, 'me asiti ea formic e loketse hantle. Asiti le aldehyde le tsona li ka eketsoa ka nako e le 'ngoe ho lumella tharollo ho feta karabelong ea ho kopanya ka har'a pH e lakatsehang. Karabelo ena hangata e sebelisoa ts'ebetsong ea ho qetela ea kalafo ts'ebetsong ea ho lokisa li-ether tsa cellulose. Kamora hore ether ea cellulose e se ke ea qhibiliha, ho bonolo ho e sebelisa.
Metsi a 20~25℃ bakeng sa ho hlatsoa le ho hloekisa. Ha sehlahisoa se sebelisoa, lintho tse nang le alkaline li ka eketsoa tharollong ea sehlahisoa ho lokisa pH ea tharollo hore e be alkaline, 'me sehlahisoa se tla qhibiliha ka potlako tharollong. Mokhoa ona o boetse oa sebetsa kalafong ea filimi ka mor'a hore tharollo ea ether ea cellulose e etsoe filimi ho e etsa filimi e sa qhibiliheng.
(7) Khanyetso ea enzyme ea hydroxypropyl methylcellulose ke lintho tse tsoang ho cellulose ka khopolo-taba, joalo ka sehlopha se seng le se seng sa anhydroglucose, haeba ho na le sehlopha se tlamahaneng ka thata, ha ho bonolo ho tšoaetsoa ke likokoana-hloko, empa ha e le hantle sehlahisoa se felileng Ha boleng ba phetisetso bo feta 1, bo tla boela bo senyehe ke lienzyme, ho bolelang hore tekanyo ea phetisetso ea sehlopha se seng le se seng ketane ea cellulose ha e tšoane ka ho lekana, 'me likokoana-hloko li ka senyeha sehlopheng sa anhydroglucose se sa nkeloang sebaka ho etsa tsoekere, e le limatlafatsi bakeng sa likokoana-hloko ho monya. Ka hona, haeba tekanyo ea phetisetso ea etherification ea cellulose e eketseha, khanyetso ea ho senyeha ha enzymatic ea ether ea cellulose le eona e tla eketseha. Ho ea ka litlaleho, tlas'a maemo a laoloang, liphello tsa hydrolysis tsa li-enzyme tse entsoeng, viscosity e setseng ea hydroxypropyl methylcellulose (DS=1.9) ke 13.2%, methylcellulose (DS=1.83) ke 7.3%, methylcellulose (DS=1.66) ke 3.8%, 'me hydroxyethyl cellulose ke 1.7%. Ho ka bonoa hore hydroxypropyl methylcellulose e na le bokhoni bo matla ba ho loantša li-enzyme. Ka hona, khanyetso e ntle ea enzyme ea hydroxypropyl methylcellulose, hammoho le thepa ea eona e ntle ea ho qhalana, ho teteana le ho etsa filimi, e sebelisoa liphahlong tsa metsi-emulsion, jj., 'me ka kakaretso ha ho hlokahale hore ho eketsoe li-preservative. Leha ho le joalo, bakeng sa polokelo ea nako e telele ea tharollo kapa tšilafalo e ka bang teng e tsoang kantle, li-preservative li ka eketsoa e le thibelo, 'me khetho e ka khethoa ho latela litlhoko tsa ho qetela tsa tharollo. Phenylmercuric acetate le manganese fluorosilicate ke li-preservative tse sebetsang, empa kaofela li na le Chefo, tlhokomelo e tlameha ho lefshoa ts'ebetsong. Ka kakaretso, 1-5mg ea phenylmercury acetate e ka eketsoa tharollong ka litara e le 'ngoe ea tekanyo.
(8) Tshebetso yahydroxypropyl methylcelluloseFilimi Hydroxypropyl methylcellulose e na le thepa e ntle ea ho etsa filimi. Tharollo ea eona ea metsi kapa tharollo ea organic solvent e koahetsoe poleiting ea khalase, 'me e fetoha e se nang 'mala le e bonaletsang ka mor'a ho oma. 'Me e thata filimi. E na le khanyetso e ntle ea mongobo 'me e lula e tiile mochesong o phahameng. Haeba hygroscopic plasticizer e eketsoa, ho lelefala le ho tenyetseha ha eona ho ka ntlafatsoa. Mabapi le ho ntlafatsa ho tenyetseha, li-plasticizer tse kang glycerin le sorbitol ke tsona tse loketseng ka ho fetisisa. Ka kakaretso, mahloriso a tharollo ke 2% ~ 3%, 'me bongata ba plasticizer ke 10% ~ 20% ea cellulose ether. Haeba litaba tsa plasticizer li le holimo haholo, ho fokotseha ha metsi ka colloidal ho tla etsahala mongobong o phahameng. Matla a ho tsikinyeha a filimi e nang le plasticizer a ekelitsoeng a maholo haholo ho feta a se nang plasticizer, 'me aa eketseha ha bongata bo ekelitsoeng. Ha e le hygroscopicity ea filimi, e boetse e eketseha ha bongata ba plasticizer bo eketseha.
Nako ea poso: Mmesa-25-2024