Thepa ea hydroxypropyl methylcellulose

Hydroxypropyl methylcellulose HPMC ke mofuta oa ether e tsoakiloeng ea cellulose e seng 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 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 qhibilihisitsoeng kapa mocheso oa flocculation litharollong tsa metsi.

(1) Thepa ea ho qhibiliha ha hydroxypropyl methylcellulose

①Ho qhibiliha ha hydroxypropyl methylcellulose ka metsing Hydroxypropyl methylcellulose ha e le hantle ke mofuta oa methylcellulose e fetotsoeng ke propylene oxide (methoxypropylene), kahoo e ntse e na le thepa e tšoanang le ea methyl cellulose 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 ka 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 ka mocheso o tšoanang e le hoo e ka bang 55°C feela. Ha e le ho qhibiliha ha eona ka 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 ka mocheso oa kamore, e qhibiliha habonolo metsing ntle le ho pholisa.

②Ho qhibiliha ha hydroxypropyl methylcellulose ka har'a metsoako ea tlhaho Ho qhibiliha ha hydroxypropyl methylcellulose ka har'a metsoako ea tlhaho le hona ho molemo ho feta ha methylcellulose. Bakeng sa lihlahisoa tse kaholimo ho 2.1, hydroxypropyl methylcellulose e nang le viscosity e phahameng e nang le hydroxypropyl MS=1.5~1.8 le methoxy DS=0.2~1.0, ka tekanyo e felletseng ea sebaka se kaholimo ho 1.8, e qhibiliha ka har'a litharollo tsa methanol le ethanol tse sa keneleng metsi. E boetse e qhibiliha ka har'a li-hydrocarbon tse nang le chlorine tse kang methylene chloride le chloroform, le metsoako ea tlhaho e kang acetone, isopropanol le diacetone alcohol. Ho qhibiliha ha eona ka har'a metsoako ea tlhaho ho molemo ho feta ho qhibiliha ha metsi.

(2) Mabaka a amang ho teteana ha hydroxypropyl methylcellulose Tekanyetso e tloaelehileng ea ho teteana ha hydroxypropyl methylcellulose e tšoana le li-ether tse ling tsa cellulose, 'me e lekanngoa ho 20°C ka tharollo ea metsi ea 2% joalo ka tekanyetso. Ho teteana ha sehlahisoa se tšoanang hoa eketseha ka keketseho ea ho teteana. Bakeng sa lihlahisoa tse nang le boima bo fapaneng ba limolek'hule ka ho teteana ho tšoanang, sehlahisoa se nang le boima bo boholo ba limolek'hule se na le ho teteana ho hoholo. Kamano ea sona le mocheso e tšoana le ea methyl cellulose. Ha mocheso o phahama, ho teteana ho qala ho fokotseha, empa ha o fihla mochesong o itseng,

viscosity e phahama ka tshohanyetso mme ho hlaha gelation. Mocheso wa gel wa dihlahiswa tse nang le viscosity e tlase o phahame. o hodimo. Ntlha ya yona ya gel ha e amane feela le viscosity ya ether, empa hape e amana le karolelano ya sebopeho sa sehlopha sa methoxyl le sehlopha sa hydroxypropyl ho ether le boholo ba tekanyo yohle ya phetolo. Ho lokela ho hlokomelwa hore hydroxypropyl methylcellulose le yona ke pseudoplastic, mme tharollo ya yona e tsitsitse mochesong wa kamore ntle le ho senyeha ha viscosity ntle le monyetla wa ho senyeha ha enzymatic.

(3) Mamello ea letsoai ea hydroxypropyl methylcellulose Kaha hydroxypropyl methylcellulose ke ether e seng ea ionic, ha e ionise metsing, ho fapana le li-ether tse ling tsa ionic cellulose, Mohlala, carboxymethyl cellulose e arabela le li-ion tsa tšepe e boima 'me e putlama ka har'a tharollo. Matsoai a akaretsang a kang chloride, bromide, phosphate, nitrate, jj. a ke ke a putlama 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 mahloriso a letsoai a eketseha, mocheso oa gel oa fokotseha. Ha mahloriso a letsoai a le ka tlase ho ntlha ea flocculation, viscosity ea tharollo e atisa ho eketseha. Ka hona, letsoai le itseng lea eketsoa. ​​, ha e sebelisoa, e ka fihlela phello ea ho teteana ka mokhoa o sireletsehileng haholoanyane. Ka hona, lits'ebetsong tse ling, ho molemo ho sebelisa motsoako oa ether ea cellulose le letsoai ho feta mahloriso a phahameng a 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 li-acid tse 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, polymethylvinylsiloxane, 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) Li-ether tsa cellulose tse sa qhibiliheng metsing tsa hydroxypropyl methylcellulose li ka hokahanngoa le li-aldehydes tse holim'a metsi, e le hore li-ether tsena tse qhibilihang metsing li kenelle ka har'a tharollo 'me li se ke tsa qhibiliha ka har'a metsi. Li-aldehydes 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 kopanya lihlahisoa tsa indasteri. Bongata ba mofuta ona oa moemeli oa ho kopanya 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, kalafo

mocheso ke 0~30℃, 'me nako ke 1~120min. Karabelo ea ho kopanya e hloka ho etsoa tlas'a maemo a asiti. Ka kakaretso, tharollo e eketsoa pele ka asiti e matla e sa tloaelehang kapa asiti ea carboxylic ea organic ho fetola pH ea tharollo ho isa ho 2~6, haholo-holo pakeng tsa 4~6, ebe e eketsa 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 hydroxyacetic, 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 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, se tla boela se 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 ea li-enzyme, 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 ya filimi ya hydroxypropyl methylcellulose Hydroxypropyl methylcellulose e na le thepa e ntle ya ho etsa filimi. Tharollo ya yona ya metsi kapa tharollo ya organic solvent e kwahetswe poleiting ya khalase, mme e fetoha e se nang mmala le e bonaletsang kamora ho oma. Mme e thata filimi. E na le kganyetso e ntle ya mongobo mme e dula e tiile mochesong o phahameng. Haeba hygroscopic plasticizer e eketswa, ho lelefala le ho tenyetseha ha yona ho ka ntlafatswa. Mabapi le ho ntlafatsa ho tenyetseha, di-plasticizer tse kang glycerin le sorbitol ke tsona tse loketseng ka ho fetisisa. Ka kakaretso, mahloriso a tharollo ke 2% ~ 3%, mme bongata ba plasticizer ke 10% ~ 20% ya cellulose ether. Haeba dikahare tsa plasticizer di le hodimo haholo, ho fokotseha ha metsi ka colloidal ho tla etsahala mongobong o phahameng. Matla a ho tsikinyeha a filimi ka

Setlolo se eketsang plasticizer se seholo haholo ho feta se se nang plasticizer, 'me sea eketseha ha bongata bo eketsoa. ​​Ha e le hygroscopicity ea filimi, e boetse e eketseha ha bongata ba plasticizer bo eketseha.