Iyini iHydroxypropyl methyl cellulose HPMC?

I-Hydroxypropyl methyl cellulose HPMC iyi-cellulose engeyona i-ionic exutshwe i-ether ehlukahlukene kanye ne-ionic methyl carboxymethyl cellulose exubile ether, ayisebenzi ngezinsimbi ezisindayo. I-oxygen radicals eyodwa ngenxa yokuqukethwe kwe-hydroxypropyl methyl cellulose kanye nengxenye ehlukene yokuqukethwe kwe-hydroxypropyl kanye ne-viscosity, yaba izinhlobo ezihlukile ekusebenzeni, isibonelo, okuqukethwe okuphezulu kwe-methoxyl nokuqukethwe okuphansi kwezinhlobo ze-hydroxypropyl, ukusebenza kwayo kuseduze ne-methyl cellulose ne-methoxyl ephansi. okuqukethwe kanye nokuqukethwe okuphezulu kwezinhlobo ze-hydroxypropyl, futhi ukusebenza kwayo kuseduze ne-hydroxypropyl methyl i-cellulose ikhiqizwa. Kodwa ezinhlobonhlobo ngayinye, nakuba iqukethe kuphela inani elincane le-hydroxypropyl noma inani elincane le-methoxy, ukuncibilika ku-solvents eziphilayo noma izinga lokushisa le-flocculation kusixazululo samanzi, kunomehluko omkhulu.
 
1, ukunyibilika kwe-hydroxypropyl methyl cellulose
IHydroxypropyl methyl cellulose ekuncibilikeni kwamanzi kwe-hydroxypropyl methyl cellulose empeleni iwuhlobo lwe-propylene oxide (i-methyl oxypropyl ring) eguquliwe i-methyl cellulose, ngakho-ke isenayo okufanayo nezici ze-methyl cellulose ezincibilika emanzini abandayo kanye nezici zamanzi ashisayo ezingancibiliki. Nokho, izinga lokushisa le-gelation le-modified hydroxy propyl liphakeme kakhulu kunalelo le-methyl cellulose emanzini ashisayo. Isibonelo, i-viscosity ye-hydroxypropyl methylcellulose isixazululo samanzi esinokuqukethwe kwe-methoxy okungu-2% DS=0.73 nokuqukethwe kwe-hydroxypropyl MS=0.46 ngu-500 mpa ku-20℃. Izinga lokushisa lejeli lomkhiqizo we-S lisondele ku-100℃, kanti lelo le-methyl cellulose lezinga lokushisa elifanayo licishe libe ngu-55℃. Ngokuqondene ne-solubility yayo emanzini, nayo ithuthukisiwe kakhulu, isibonelo, ngemva kokuchotshozwa kwe-hydroxypropyl methylcellulose (isimo sokusanhlamvu 0.2 ~ 0.5mm ku-20 ℃ 4% viscosity enamanzi ye-2pA? Imikhiqizo ye-S ingancibilika kalula emanzini ngaphandle kokupholisa ekamelweni lokushisa. .
 
(2) I-Hydroxypropyl methyl cellulose ku-organic solvents solubility ye-hydroxypropyl methyl cellulose ku-organic solvents solubility, futhi ingcono kune-methyl cellulose, i-methyl cellulose idinga ku-methoxy substitution degree yemikhiqizo engu-2.1 noma ngaphezulu, futhi iqukethe i-hydroxypropyl MS=1.5~1.8 kanye ne-methoxy DS=0.2~1.0, I-viscosity ephezulu I-hydroxypropyl methyl cellulose enedigri ephelele yokushintsha ngaphezu kwe-1.8 iyancibilika ku-anhydrous methanol nezixazululo ze-ethanol, futhi ine-thermoplastic ne-solubility yamanzi. Iphinde inyibilike kuma-hydrocarbon ane-chlorine afana ne-dichloromethane ne-trichloromethane, nezinyibilikisi eziphilayo njenge-acetone, i-isopropyl alcohol, ne-diacetone alcohol. Ukuncibilika kwawo kuzincibilikisi zemvelo kudlula ukuncibilika kwamanzi.
 
2, i-hydroxypropyl methyl cellulose viscosity yezinto ezinomthelela
I-Hydroxypropyl methylcellulose viscosity factor hydroxypropyl methylcellulose standard viscosity determination, kanye nenye i-cellulose ether iyafana, iku-20℃ nesisombululo samanzi esingu-2% njengokunqunywa okujwayelekile. I-viscosity yomkhiqizo ofanayo, ngokukhula kokugxila nokwanda, ukuhlushwa okufanayo kwemikhiqizo ehlukene yamangqamuzana, isisindo samangqamuzana omkhiqizo yi-viscosity ephezulu. Ubudlelwano bayo nezinga lokushisa bufana nobe-methyl cellulose. Lapho izinga lokushisa likhuphuka, i-viscosity iqala ukwehla, kodwa lapho ifinyelela izinga lokushisa elithile, i-viscosity iphakama ngokuzumayo futhi i-gelation ivela. Izinga lokushisa le-gelation lemikhiqizo ene-viscosity ephansi liphakeme kunelemikhiqizo ene-viscosity ephezulu. Izinga lephoyinti layo lejeli, ngaphezu kwe-viscosity ephezulu nephansi ye-ether, kodwa futhi ne-ether methoxy ne-hydroxypropyl group composition ratio kanye nenani eliphelele lokushintsha kuhlobene. Kumele kuqashelwe ukuthi i-hydroxypropyl methylcellulose nayo iyi-pseudoplastic; isisombululo saso sizinzile uma sigcinwe ekamelweni lokushisa futhi asibonisi noma yikuphi ukuwohloka kwe-viscosity ngaphandle kokuthi kungenzeka ukuwohloka kwe-enzymatic.
 
3, i-hydroxypropyl methyl cellulose acid kanye nokumelana ne-alkali
I-Hydroxypropyl methylcellulose acid i-alkali hydroxypropyl methylcellulose acid ne-alkali, ngokuvamile izinzile, kuhla lwe-ph PH2~12 ayithinteki, ingamelana nenani elithile le-asidi ekhanyayo, njenge-formic acid, i-acetic acid, i-citric acid, i-succinic acid, i-phosphoric i-asidi, i-boric acid, njll Kodwa i-asidi egxilile inomphumela wokunciphisa i-viscosity. I-alkali efana ne-caustic soda, i-caustic potassium kanye namanzi e-lime ayinamthelela kuwo, kodwa umphumela wokwandisa kancane i-viscosity yesisombululo uzokwehla kancane kancane esikhathini esizayo.
 
4, i-hydroxypropyl methyl cellulose ingaxutshwa
Isixazululo se-Hydroxypropyl methyl cellulose singaxutshwa nezinhlanganisela ze-polymer ezincibilika emanzini, futhi sibe isixazululo esisobala esifanayo esine-viscosity ephezulu. Lezi zinhlanganisela zamangqamuzana aphezulu i-polyethylene glycol, i-polyvinyl acetate, i-polysilicone, i-polymethyl vinyl siloxane ne-hydroxyethyl cellulose ne-methyl cellulose, njll. Izinhlanganisela ze-polymer zemvelo ezifana ne-gum Arabic, i-locust bean gum, i-thorn tree gum nokunye isisombululo. IHydroxypropyl methyl cellulose ingabuye ixutshwe ne-stearic acid noma i-palmitic acid mannitol ester noma i-sorbitol ester, kodwa futhi ne-glycerol, i-sorbitol ne-mannitol, lezi zinhlanganisela zingasetshenziswa njenge-hydroxypropyl methyl cellulose plasticizer.
 
5, i-hydroxypropyl methyl cellulose engancibiliki emanzini
IHydroxypropyl methyl cellulose i-insoluble water-soluble cellulose ether, ingaba phezulu exhumanisa ama-aldehyde, futhi yenze le ether encibilika emanzini iwa esixazululo, ingancibiliki emanzini. Futhi wenze i-hydroxypropyl methylcellulose i-aldehyde engaselubiliki, i-formaldehyde, i-glyoxal, i-succinaldehyde, i-dialdehyde, njll., ukusetshenziswa kwe-formaldehyde kufanele kunake ngokukhethekile ukubaluleka kwe-PH yesisombululo, lapho ukusabela kwe-glyoxal ngokushesha, ngakho-ke ekukhiqizeni izimboni ngokuvamile kusetshenziswa i-glyoxal njengesiphambano. - i-ejenti yokuxhumana. Umthamo walolu hlobo lwe-agent exhumanisayo esixazululweni ngu-0.2% ~ 10% wesisindo se-ether, engcono kakhulu ngu-7% ~ 10%, njengokusetshenziswa kwe-glyoxal no-3.3% ~ 6% iyona efanele kakhulu. Izinga lokushisa elijwayelekile lokwelapha ngu-0~30℃, isikhathi singu-1~120min. Ukusabela kwe-cross-linking kufanele kwenziwe ngaphansi kwezimo ze-acidic. Ngokuvamile, i-asidi eqinile ye-inorganic noma i-organic carboxylic acid yengezwa esixazululo ukulungisa i-PH yesisombululo ibe cishe ku-2~6, okungcono kakhulu phakathi kuka-4~6, bese kwengezwa ama-aldehyde ukuze kuhlanganiswe ukuhlangana. Ama-acids asetshenziswa i-hydrochloric acid, i-sulfuric acid, i-phosphoric acid, i-fomic acid, i-acetic acid, i-hydroxy acetic acid, i-succinic acid noma i-citric acid, phakathi kwayo i-formic acid noma i-acetic acid ihamba phambili, kuyilapho i-formic acid ihamba phambili. Ama-Acid nama-aldehyde nawo angase angezwe ngesikhathi esifanayo ukuze kuvunyelwe ikhambi ukuthi lixhunywe kububanzi obufunwayo be-PH. Lokhu kusabela kuvame ukusetshenziswa kunqubo yokugcina yenqubo yokulungiselela i-cellulose ether, ukuze i-cellulose ether ingancibiliki, kulula ukuyisebenzisa 20~25℃ amanzi ukuwasha nokuhlanza. Uma umkhiqizo usetshenziswa, izinto ze-alkaline zingangezwa kwisixazululo somkhiqizo ukuze kulungiswe i-PH yesisombululo ukuze ibe yi-alkaline, futhi umkhiqizo uhlakazeka ngokushesha esixazululweni. Le ndlela ingasetshenziswa futhi lapho isisombululo se-cellulose ether sisetshenziselwa ukwenza ifilimu bese ifilimu iphathwa ukwenza ifilimu engancibiliki.
 
6, i-hydroxypropyl methyl cellulose anti-enzyme
I-Hydroxypropyl methyl cellulose enzyme ukumelana kokuphuma kwe-cellulose ngokombono, njengamaqembu e-anhydroglucose ngayinye njengokuthi kunenhlanganisela eqinile yokuthatha indawo yamaqembu, ukuguguleka kwama-microorganisms akulula ukungenwa ukutheleleka, kodwa empeleni umkhiqizo oqediwe wokubuyisela inani elingaphezu kwe-1, futhi ngokuwohloka kwe-enzyme, lena incazelo yeqembu ngalinye ku-cellulose chain substitution degree ayifani, ama-Microorganisms angakwazi guguleka eduze kwamaqembu eglucose ephelelwe amanzi engashintshiwe ukuze akhe ushukela, ongamuncwa amagciwane njengokudla. Ngakho-ke, uma izinga lokushintshwa kwe-etherification le-cellulose likhuphuka, ukumelana kwe-cellulose ether nokuguguleka kwe-enzymatic kuzothuthukiswa. Kubikwa ukuthi ngaphansi kwezimo ezilawulwayo, i-viscosity eyinsalela ye-hydroxypropyl methyl cellulose (DS=1.9), i-methyl cellulose (DS=1.83), i-methyl cellulose (DS=1.66), kanye ne-hydroxyethyl cellulose (1.7%) yayingu-13.2%, 7.3% , 3.8%, no-1.7%, ngokulandelana. I-Hydroxypropyl methyl cellulose inekhono eliqinile lokulwa nama-enzyme. Ngakho-ke i-hydroxypropyl methylcellulose i-anti-enzyme enhle kakhulu, ehlangene nokuhlakazeka kwayo okuhle, ukuqina kanye nokwakheka kwefilimu, esetshenziswe emigqonyeni ye-emulsion, njll, ngokuvamile ayidingi ukwengeza ama-preservatives. Kodwa-ke, ukuze kuvinjwe ukugcinwa kwesixazululo isikhathi eside noma ukungcola okungenzeka okuvela emhlabeni wangaphandle, izilondolozi zingangezwa, okukhethwa kwazo kunganqunywa ngokuvumelana nezidingo zokugcina zesisombululo. I-Phenylmercuric acetate kanye ne-manganese fluosilicate yizilondolozi ezisebenzayo, kodwa zinobuthi futhi kufanele zisetshenziswe ngokucophelela. Ngokuvamile, i-1 ~ 5mg i-phenylmercuric acetate ingafakwa ilitha ngalinye lesisombululo.
 
7, ukusebenza kwe-hydroxypropyl methyl cellulose membrane
Ukusebenza kwefilimu ye-Hydroxypropyl methyl cellulose ye-hydroxypropyl methyl cellulose inefilimu enhle kakhulu, isixazululo sayo esinamanzi noma isixazululo se-organic solvent, embozwe epuleti lengilazi, ngemva kokoma iba ifilimu engenambala, esobala futhi eqinile. Inokumelana okuhle nomswakama futhi ihlala iqinile emazingeni okushisa aphezulu. Njengokwengezwa kwe-plasticizer ye-hygroscopic, kungathuthukisa ubude bayo nokuguquguquka, ukuthuthukisa ukuguquguquka, i-glycerol ne-sorbitol nezinye i-plasticizer ezifanele kakhulu. Isixazululo esijwayelekile singu-2% ~ 3%, umthamo we-plasticizer ngu-10% ~ 20% we-cellulose ether. Uma okuqukethwe kwe-plasticizer kutholakala, ukwenzeka kokuncipha kwe-colloid dehydration kungenzeka kumswakama ophezulu. Amandla aqinile wefilimu afakwe i-plasticizer makhulu kakhulu kunalawo angangeziwe, futhi ayanda ngokunyuka kwenani elingeziwe, njengoba i-hygroscopicity yefilimu nayo iyanda ngokunyuka kwenani le-plasticizer.


Isikhathi sokuthumela: Sep-08-2022