Hydroxypropyl methyl cellulose HPMC ndi mtundu wa non-ionic cellulose wosakaniza ether, womwe ndi wosiyana ndi ionic methyl carboxymethyl cellulose ether wosakanikirana, ndipo sichichita ndi zitsulo zolemera.Chifukwa cha kusiyanasiyana kwa methoxyl ndi hydroxypropyl zomwe zili mu hydroxypropyl methylcellulose ndi ma viscosities osiyanasiyana, zakhala mitundu yosiyanasiyana yokhala ndi zinthu zosiyanasiyana, mwachitsanzo, kuchuluka kwa methoxyl komanso kutsika kwa hydroxypropyl Kuchita kwake kuli pafupi ndi cellulose ya methyl, ndi mitundu yokhala ndi methoxyl yotsika komanso kuchuluka kwa hydroxypropyl, magwiridwe ake ndi oyandikira a hydroxypropyl methylcellulose.Komabe, mumitundu yosiyanasiyana, ngakhale kuti pali gulu laling'ono la hydroxypropyl kapena gulu laling'ono la methoxy, kusungunuka kwa zosungunulira za organic kapena kutentha kwa flocculation mu njira yamadzimadzi ndizosiyana kwambiri.
1. Kusungunuka kwa hydroxypropyl methylcellulose
①Kusungunuka kwa hydroxypropyl methyl cellulose m'madzi Hydroxypropyl methyl cellulose kwenikweni ndi methyl cellulose yosinthidwa ndi propylene oxide (methyl oxypropylene), kotero imakhalabe ndi zinthu zomwezo ngati methyl cellulose.Ma cellulose amafanana ndi kusungunuka kwamadzi ozizira komanso kusasungunuka kwamadzi otentha.Komabe, chifukwa cha gulu losinthidwa la hydroxypropyl, kutentha kwake kwa gelation m'madzi otentha ndikokwera kwambiri kuposa methyl cellulose.Mwachitsanzo, kukhuthala kwa njira yamadzi ya hydroxypropyl methylcellulose yokhala ndi 2% methoxyl content DS=0.73 ndi hydroxypropyl content MS=0.46 ndi 500 mpa?s pa 20°C.Kutentha kwake kwa gel Imatha kufika pafupifupi 100 ° C, pomwe methylcellulose pa kutentha komweko ndi pafupifupi 55 ° C.Ponena za kusungunuka kwake m'madzi, zasinthidwanso kwambiri.Mwachitsanzo, pulverized hydroxypropyl methylcellulose (granular mawonekedwe a 0.2 ~ 0.5mm pa 20°C ndi mamasukidwe akayendedwe a 4% amadzimadzi njira mpaka 2pa?s?
②Kusungunuka kwa hydroxypropyl methyl cellulose mu zosungunulira za organic Kusungunuka kwa hydroxypropyl methyl cellulose mu zosungunulira za organic kulinso kwabwino kuposa kwa methyl cellulose, ndipo methyl cellulose imayenera kukhala ndi digiri ya methoxyl m'malo mwa Zogulitsa pamwamba pa 2.1, ndi ma high-viscosity okhala ndi methylcellulose hydroxypropyl MS = 1.5 ~ 1.8 ndi methoxy DS=0.2 ~ 1.0, ndipo okwana digiri m'malo pamwamba 1.8 amasungunuka mu anhydrous methanol ndi Mowa njira sing'anga, thermoplastic ndi madzi sungunuka.Amasungunukanso mu ma chlorinated hydrocarbons monga dichloromethane ndi chloroform, komanso muzosungunulira organic monga acetone, isopropanol ndi diacetone mowa.Kusungunuka kwake mu zosungunulira za organic ndikwabwino kuposa kusungunuka m'madzi.
2. Zinthu zomwe zimakhudza kukhuthala kwa hydroxypropyl methylcellulose
Zomwe zimakhudzidwa ndi hydroxypropyl methyl cellulose viscosity Kutsimikiza kwa kukhuthala kwa hydroxypropyl methyl cellulose, monga ma cellulose ethers, kumatengera njira yamadzi 2% pa 20°C.Kukhuthala kwa mankhwala omwewo kumawonjezeka ndi kuwonjezeka kwa ndende.Pazinthu zokhala ndi mamolekyu osiyanasiyana pamlingo womwewo, zinthu zomwe zimakhala ndi zolemera zazikulu zama cell zimakhala ndi kukhuthala kwakukulu.Ubale wake ndi kutentha ndi wofanana ndi wa methyl cellulose.Kutentha kumawonjezeka, kukhuthala kumayamba kuchepa, koma ikafika kutentha kwina, kukhuthala kumawonjezeka mwadzidzidzi ndipo gelation imachitika.Kutentha kwa gel otsika-kukhuthala kwakanthawi ndikokwera kwambiri.ndi mkulu.Mfundo yake ya gel sikuti imangogwirizana ndi kukhuthala kwa ether, komanso kusakanikirana kwa methoxy ndi hydroxypropyl mu ether ndi chiwerengero chonse cha m'malo.Tiyenera kuzindikira kuti hydroxypropyl methylcellulose imakhalanso pseudoplastic ndipo yankho lake ndi lokhazikika pa kutentha kwa firiji popanda kuwonongeka kwa viscosity kupatula kuthekera kwa kuwonongeka kwa enzymatic.
3. Hydroxypropyl methylcellulose acid ndi kukana kwa alkali
Hydroxypropyl methylcellulose acid ndi alkali resistance Hydroxypropyl methylcellulose nthawi zambiri imakhala yokhazikika ku asidi ndi alkali, ndipo sichikhudzidwa ndi pH 2 ~ 12.Imatha kupirira kuchuluka kwa asidi wopepuka.Monga asidi formic, asidi asidi, citric asidi, succinic asidi, asidi phosphoric, asidi boric, etc. Komabe, ndende asidi ali ndi zotsatira za kuchepetsa mamasukidwe akayendedwe.Alkali monga caustic soda, caustic potashi ndi laimu madzi alibe mphamvu pa izo, koma pang'ono kuonjezera mamasukidwe akayendedwe a yankho, ndiyeno padzakhala chodabwitsa kuchepa pang'onopang'ono m'tsogolo.
4. Kusakanikirana kwa hydroxypropyl methylcellulose
Miscibility wa Hydroxypropyl Methyl Cellulose Hydroxypropyl methyl cellulose njira akhoza kusakaniza ndi madzi sungunuka polima pawiri kukhala yunifolomu ndi mandala njira ndi apamwamba mamasukidwe akayendedwe.Ma polima awa akuphatikizapo polyethylene glycol, polyvinyl acetate, polysiloxane, polymethyl vinyl siloxane, hydroxyethyl cellulose ndi methyl cellulose.Zosakaniza zachilengedwe za polima monga chingamu arabic, dzombe chingamu, karaya chingamu, ndi zina zotero zimakhalanso ndi kusakaniza bwino ndi yankho lake.Hydroxypropyl methylcellulose imathanso kusakanizidwa ndi mannitol kapena sorbitol esters ya stearic acid kapena palmitic acid, komanso imatha kusakanizidwa ndi glycerin, sorbitol ndi mannitol.Mankhwalawa amatha kugwiritsidwa ntchito ngati hydroxypropyl methylcellulose.Plasticizer yopangidwa ndi cellulose.
5. Kusasungunuka ndi kusungunuka kwa madzi kwa hydroxypropyl methylcellulose
Ma insolubilized cellulose cellulose ethers a hydroxypropyl methylcellulose amatha kuphatikizika ndi aldehydes, ndipo ma ether osungunuka m'madziwa amalowetsedwa munjirayo ndikukhala osasungunuka m'madzi.Ma aldehydes omwe amapanga hydroxypropyl methylcellulose osasungunuka amaphatikizapo formaldehyde, glyoxal, succinaldehyde, adipaldehyde, ndi zina. Mukamagwiritsa ntchito formaldehyde, chidwi chapadera chiyenera kuperekedwa ku pH ya yankho, yomwe glyoxal imachita mofulumira.Chifukwa chake, glyoxal imagwiritsidwa ntchito ngati njira yolumikizirana popanga mafakitale.Mlingo wa mtundu uwu wa crosslinking wothandizira mu yankho ndi 0,2% ~ 10% ya misa etere, makamaka 7% ~ 10%, ndi 3.3% ~ 6% ndi oyenera kwambiri glyoxal.Kutentha kwamankhwala ambiri ndi 0 ~ 30 ℃, ndipo nthawi ndi 1 ~ 120min.Kuphatikizika kolumikizana kuyenera kuchitika pansi pa acidic.Nthawi zambiri, asidi amphamvu kapena organic carboxylic acid amawonjezedwa ku yankho kuti asinthe pH ya yankho kukhala pafupifupi 2 ~ 6, makamaka pakati pa 4 ~ 6, kenako ma aldehydes amawonjezedwa kuti achite zomwe zimagwirizanitsa..Ma acid omwe amagwiritsidwa ntchito ndi monga hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, hydroxyacetic acid, succinic acid kapena citric acid, yomwe imakhala yoyenera, ndipo formic acid ndi yabwino kwambiri.Asidi ndi aldehyde amathanso kuwonjezeredwa nthawi imodzi kuti alole yankho kuti lidutse mumtundu womwe mukufuna.Izi nthawi zambiri amagwiritsidwa ntchito pomaliza chithandizo pokonzekera ma cellulose ethers.Pambuyo pa ether cellulose insolubilized, ndi bwino kutsuka ndi kuyeretsa ndi madzi pa 20 ~ 25 ° C.Pamene mankhwalawa akugwiritsidwa ntchito, mankhwala a alkaline amatha kuwonjezeredwa ku yankho la mankhwala kuti asinthe pH ya yankho kuti ikhale yamchere, ndipo mankhwalawo amatha kusungunuka mwamsanga.Njirayi imagwiranso ntchito pazitsulo za cellulose ether zomwe zimapangidwira filimu ndiyeno filimuyo imakonzedwa kuti ikhale filimu yosasungunuka.
6. Hydroxypropyl methylcellulose imagonjetsedwa ndi michere
Hydroxypropyl methylcellulose imagonjetsedwa ndi michere.Mwachidziwitso, zotumphukira za cellulose, monga gulu lililonse la anhydroglucose, zimakhala ndi gulu lokhazikika lokhazikika, lomwe silosavuta kutenga kachilomboka ndi tizilombo tating'onoting'ono, koma kwenikweni mankhwala omalizidwa Pamene mtengo wolowa m'malo upitilira 1, nawonso udzasokonezedwa ndi michere, kutanthauza kuti mlingo wa m'malo gulu lililonse pa unyolo mapadi si yunifolomu mokwanira, ndi tizilombo akhoza kukokoloka pafupi unsubstituted anhydroglucose magulu kupanga shuga., zomwe zimatengedwa ngati chakudya cha tizilombo toyambitsa matenda.Choncho, ngati etherification m'malo digiri ya mapadi ukuwonjezeka, kukana kwa enzymatic kukokoloka kwa mapadi ether kumathekanso.Zimanenedwa kuti kukhuthala kotsalira kwa hydroxypropyl methylcellulose (DS = 1.9) ndi 13.2%, methylcellulose (DS = 1.83) ndi 7.3%, ndi methylcellulose (DS = 1.66) ndi 3.8%, ndi hydroxyethyl cellulose ndi 1.7%.Zitha kuwoneka kuti mphamvu ya anti-enzyme ya hydroxypropyl methylcellulose ndi yamphamvu.Choncho, kukana bwino kwa enzyme ya hydroxypropyl methylcellulose, kuphatikizapo dispersibility yake yabwino, thickening ndi kupanga mafilimu, nthawi zambiri amagwiritsidwa ntchito mu zokutira za emulsion zamadzi, ndi zina zotero, ndipo kawirikawiri sizifuna kuwonjezera zotetezera.Komabe, pofuna kusungirako kwa nthawi yaitali yankho kapena kuipitsidwa kwa dziko lakunja, zotetezera zimatha kuwonjezeredwa ngati njira yodzitetezera, ndipo chisankho chikhoza kutsimikiziridwa molingana ndi zofunikira zomaliza za yankho.Phenylmercuric acetate ndi manganese fluorosilicate ndi zotetezera zogwira mtima, koma zonse zili ndi Toxicity, chidwi chiyenera kuperekedwa ku opaleshoni, ndipo mlingo nthawi zambiri ndi 1 ~ 5mg wa phenylmercuric acetate pa lita imodzi ya yankho.
7. Katundu wa filimu ya hydroxypropyl methylcellulose
Ntchito ya filimu ya hydroxypropyl methylcellulose Hydroxypropyl methylcellulose imakhala ndi zinthu zabwino kwambiri zopangira filimu, ndipo njira yake yamadzimadzi kapena organic solvent solution imakutidwa pa mbale yagalasi, ndipo imakhala yopanda mtundu komanso yowonekera pambuyo poyanika.Ndipo filimu yovuta.Ili ndi kukana kwabwino kwa chinyezi ndipo imakhalabe yolimba pa kutentha kwakukulu.Mwachitsanzo, kuwonjezera pulasitiki wa hygroscopic kumatha kukulitsa kutalika kwake komanso kusinthasintha.Pofuna kusinthasintha, mapulasitiki opangira zinthu monga glycerin ndi sorbitol ndi abwino kwambiri.Ambiri yankho ndende ndi 2% ~ 3%, ndipo kuchuluka kwa plasticizer ndi 10% ~ 20% ya mapadi ether.Ngati zomwe zili mu plasticizer ndizokwera kwambiri, vuto la kuchepa kwa madzi m'thupi la colloid limachitika pansi pa chinyezi chambiri.Mphamvu yolimba ya filimuyo yokhala ndi pulasitiki yowonjezeredwa ndi yayikulu kwambiri kuposa yopanda pulasitiki, ndipo imawonjezeka ndi kuchuluka kwa ndalama zowonjezera.Ponena za hygroscopicity ya filimuyi, imawonjezekanso ndi kuchuluka kwa plasticizer.
Nthawi yotumiza: Oct-13-2022