Kodi Hydroxypropyl methyl cellulose HPMC ndi chiyani?

Hydroxypropyl methyl cellulose HPMC ndi ether yosakanikirana ya cellulose yosakhala ionic mu mitundu yosiyanasiyana ndipo ionic methyl carboxymethyl cellulose yosakanikirana ether, sichitapo kanthu ndi zitsulo zolemera. Chimodzi mwa zinthu zomwe zimapangitsa kuti mpweya ukhale woipa chifukwa cha kuchuluka kwa hydroxypropyl methyl cellulose ndi kuchuluka kosiyana kwa kuchuluka kwa hydroxypropyl ndi kukhuthala, chinakhala mitundu yosiyana pakuchita bwino, mwachitsanzo, kuchuluka kwa methoxyl ndi kuchuluka kochepa kwa mitundu ya hydroxypropyl, magwiridwe ake ali pafupi ndi methyl cellulose ndi kuchuluka kochepa kwa methoxyl ndi kuchuluka kwakukulu kwa mitundu ya hydroxypropyl, ndipo magwiridwe ake ali pafupi ndi hydroxypropyl methyl cellulose yomwe imapangidwa. Koma mu mtundu uliwonse, ngakhale muli hydroxypropyl yochepa kapena kuchuluka kochepa kwa methoxy, kusungunuka mu organic solvents kapena kutentha kwa flocculation mu yankho lamadzi, pali kusiyana kwakukulu.
 
1, kusungunuka kwa hydroxypropyl methyl cellulose
Hydroxypropyl methyl cellulose mu madzi osungunuka a hydroxypropyl methyl cellulose kwenikweni ndi mtundu wa propylene oxide (methyl oxypropyl ring) modified methyl cellulose, kotero imakhalabe ndi mawonekedwe ofanana ndi methyl cellulose ozizira omwe amasungunuka komanso osasungunuka m'madzi otentha. Komabe, kutentha kwa gelation kwa modified hydroxy propyl ndi kwakukulu kwambiri kuposa kwa methyl cellulose m'madzi otentha. Mwachitsanzo, kukhuthala kwa hydroxypropyl methylcellulose aqueous solution yokhala ndi 2% methoxy content DS=0.73 ndi hydroxypropyl content MS=0.46 ndi 500 mpa pa 20℃. Kutentha kwa gel kwa S's product kuli pafupi ndi 100℃, pomwe kwa methyl cellulose ya kutentha komweko ndi pafupifupi 55℃ yokha. Ponena za kusungunuka kwake m'madzi, kunakhalanso bwino kwambiri, mwachitsanzo, pambuyo poti hydroxypropyl methylcellulose yaphwanyidwa (mawonekedwe a tirigu 0.2 ~ 0.5mm pa 20℃ 4% aqueous viscosity ya 2pA? S products zimatha kusungunuka mosavuta m'madzi popanda kuzizira kutentha kwa chipinda.
 
(2) Hydroxypropyl methyl cellulose mu organic solvents kusungunuka kwa hydroxypropyl methyl cellulose mu organic solvents kusungunuka, komanso ndi bwino kuposa methyl cellulose, methyl cellulose imafunika mu methoxy substitution degree ya 2.1 kapena kuposerapo, ndipo ili ndi hydroxypropyl MS=1.5~1.8 ndi methoxy DS=0.2~1.0, Hydroxypropyl methyl cellulose yokhala ndi ma viscosity apamwamba kwambiri yokhala ndi ma total substitution degree opitilira 1.8 imasungunuka mu anhydrous methanol ndi ethanol solutions, ndipo ili ndi thermoplastic ndi water solubility. Imasungunukanso mu chlorinated hydrocarbons monga dichloromethane ndi trichloromethane, ndi organic solvents monga acetone, isopropyl alcohol, ndi diacetone alcohol. Kusungunuka kwake mu organic solvents ndikwabwino kuposa madzi solvents.
 
2, kukhuthala kwa hydroxypropyl methyl cellulose kwa zinthu zomwe zimakhudza
Hydroxypropyl methylcellulose viscosity factors hydroxypropyl methylcellulose standard viscosity determination, ndi cellulose ether ina ndi yofanana, ili pa 20℃ ndi 2% aqueous solution monga standard determination. Viscosity ya chinthu chomwecho, ndi kuwonjezeka kwa concentration ndi kuwonjezeka, concentration yofanana ya zinthu zosiyanasiyana molecular weight, molecular weight ya chinthucho ndi high viscosity. Ubale wake ndi kutentha ndi wofanana ndi wa methyl cellulose. Pamene kutentha kukukwera, viscosity imayamba kuchepa, koma ikafika kutentha kwina, viscosity imakwera mwadzidzidzi ndipo gelation imachitika. Gelation kutentha kwa zinthu zomwe zili ndi viscosity yotsika ndi yayikulu kuposa ya zinthu zomwe zili ndi viscosity yokwera. Mlingo wa gel point yake, kuwonjezera pa viscosity yokwera ndi yotsika ya ether, komanso ndi ether methoxy ndi hydroxypropyl group composition ratio ndi total degree of substitution zimagwirizana. Tiyenera kudziwa kuti hydroxypropyl methylcellulose ndi pseudoplastic; yankho lake ndi lokhazikika likasungidwa kutentha kwa chipinda ndipo siliwonetsa kuwonongeka kulikonse kwa viscosity kupatula kuthekera kwa enzymatic degeneration.
 
3, hydroxypropyl methyl cellulose acid ndi kukana kwa alkaline
Hydroxypropyl methylcellulose acid alkali hydroxypropyl methylcellulose acid ndi alkali, nthawi zambiri zimakhala zokhazikika, mu PH PH2 ~ 12 sizimakhudzidwa, zimatha kupirira kuchuluka kwa asidi wopepuka, monga formic acid, acetic acid, citric acid, succinic acid, phosphoric acid, boric acid, ndi zina zotero. Koma asidi wokhuthala amakhala ndi mphamvu yochepetsera kukhuthala. Alkali monga caustic soda, caustic potaziyamu ndi madzi a mandimu sizimakhudza, koma zotsatira za kuchulukitsa pang'ono kukhuthala kwa yankho zidzachepa pang'onopang'ono mtsogolo.
 
4, hydroxypropyl methyl cellulose ikhoza kusakanikirana
Mankhwala a Hydroxypropyl methyl cellulose amatha kusakanizidwa ndi mankhwala a polymer osungunuka m'madzi, ndipo amakhala yankho lowonekera bwino lomwe lili ndi kukhuthala kwakukulu. Mankhwalawa apamwamba kwambiri ndi polyethylene glycol, polyvinyl acetate, polysilicone, polymethyl vinyl siloxane ndi hydroxyethyl cellulose ndi methyl cellulose, ndi zina zotero. Mankhwala achilengedwe a polymer monga gum Arabic, locustbean gum, thorn tree gum ndi zina zotero alinso ndi chisakanizo chabwino ndi yankho lake. Hydroxypropyl methyl cellulose imatha kusakanizidwanso ndi stearic acid kapena palmitic acid mannitol ester kapena sorbitol ester, komanso ndi glycerol, sorbitol ndi mannitol, mankhwala awa angagwiritsidwe ntchito ngati hydroxypropyl methyl cellulose plasticizer.
 
5, hydroxypropyl methyl cellulose yosasungunuka m'madzi
Hydroxypropyl methyl cellulose ether yosasungunuka m'madzi yosungunuka m'madzi, ikhoza kulumikizidwa ndi aldehydes pamwamba, ndipo imapangitsa kuti ether iyi yosungunuka m'madzi ikhale yosasungunuka m'madzi. Ndipo imapangitsa kuti hydroxypropyl methylcellulose isasungunuke aldehyde, formaldehyde, glyoxal, succinaldehyde, dialdehyde, ndi zina zotero, kugwiritsa ntchito formaldehyde kuyenera kusamala kwambiri ndi PH ya yankho, momwe glyoxal imachitira mofulumira, kotero kupanga mafakitale kumagwiritsidwa ntchito kwambiri glyoxal ngati wothandizira wolumikizirana. Mlingo wa mankhwalawa ndi 0.2% ~ 10% ya kulemera kwa ether, yabwino kwambiri ndi 7% ~ 10%, monga kugwiritsa ntchito glyoxal ndi 3.3% ~ 6% ndiyo yoyenera kwambiri. Kutentha kwa mankhwala ambiri ndi 0 ~ 30℃, nthawi ndi 1 ~ 120min. Kuyanjana kwa crosslinking kuyenera kuchitika pansi pa acidic. Kawirikawiri, asidi wamphamvu wosapangidwa ndi zinthu zina kapena organic carboxylic acid amawonjezeredwa ku yankho kuti asinthe PH ya yankho kukhala pafupifupi 2 ~ 6, makamaka pakati pa 4 ~ 6, kenako ma aldehydes amawonjezeredwa kuti agwirizane. Ma acid omwe amagwiritsidwa ntchito ndi hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, hydroxy acetic acid, succinic acid kapena citric acid, pakati pawo formic acid kapena acetic acid ndiye abwino kwambiri, pomwe formic acid ndiye yabwino kwambiri. Ma acid ndi ma aldehydes amathanso kuwonjezeredwa nthawi yomweyo kuti yankho ligwirizane ndi PH yomwe mukufuna. Izi nthawi zambiri zimagwiritsidwa ntchito pomaliza njira yokonzekera cellulose ether, kuti cellulose ether isasungunuke, yosavuta kugwiritsa ntchito madzi 20 ~ 25℃ kuti isambitsidwe ndikutsukidwa. Mankhwala akagwiritsidwa ntchito, zinthu za alkaline zitha kuwonjezeredwa ku yankho la mankhwala kuti asinthe PH ya yankho kukhala ya alkaline, ndipo mankhwalawa amasungunuka mwachangu mu yankho. Njirayi ingagwiritsidwenso ntchito pamene njira ya ether ya cellulose ikugwiritsidwa ntchito popanga filimu kenako filimuyo imakonzedwa kuti ipange filimu yosasungunuka.
 
6, hydroxypropyl methyl cellulose anti-enzyme
Hydroxypropyl methyl cellulose enzyme resistance of cellulose derivatives in theory, monga magulu onse a anhydroglucose monga pali kuphatikiza kolimba kwa magulu olowa m'malo, kuwonongeka kwa tizilombo toyambitsa matenda sikukhudzidwa kwambiri ndi matenda, koma kwenikweni chinthu chomalizidwa kuti chilowe m'malo mwa mtengo woposa 1, komanso ndi kuwonongeka kwa enzyme, uku ndi kufotokoza kwa gulu lililonse mu digiri ya cellulose chain substitution sikofanana, Tizilombo toyambitsa matenda tingawonongeke pafupi ndi magulu a shuga osasinthidwa kuti apange shuga, omwe amatha kuyamwa ndi tizilombo ngati chakudya. Chifukwa chake, ngati digiri ya etherification substitution ya cellulose ikuwonjezeka, kukana kwa cellulose ether ku enzymatic erosion kudzawonjezeka. Zanenedwa kuti pansi pa mikhalidwe yolamulidwa, kukhuthala kotsalira kwa hydroxypropyl methyl cellulose (DS=1.9), methyl cellulose (DS=1.83), methyl cellulose (DS=1.66), ndi hydroxyethyl cellulose (1.7%) kunali 13.2%, 7.3%, 3.8%, ndi 1.7%, motsatana. Hydroxypropyl methyl cellulose ili ndi mphamvu yolimbana ndi ma enzyme amphamvu. Chifukwa chake hydroxypropyl methylcellulose ndi anti-enzyme yabwino kwambiri, kuphatikiza ndi kufalikira kwake bwino, kukhuthala ndi mapangidwe a filimu, yogwiritsidwa ntchito mu emulsion coatings, ndi zina zotero, nthawi zambiri sikufunika kuwonjezera zosungira. Komabe, kuti tipewe kusungidwa kwa yankho kwa nthawi yayitali kapena kuipitsidwa komwe kungachitike kuchokera kudziko lakunja, zosungira zitha kuwonjezeredwa, zomwe kusankha kwake kungadziwike malinga ndi zofunikira zomaliza za yankho. Phenylmercuric acetate ndi manganese fluosilicate ndi zosungira zothandiza, koma ndi zakupha ndipo ziyenera kugwiritsidwa ntchito mosamala. Kawirikawiri, 1~5mg phenylmercuric acetate ikhoza kuwonjezeredwa pa lita iliyonse ya yankho.
 
7, magwiridwe antchito a nembanemba ya hydroxypropyl methyl cellulose
Kapangidwe ka filimu ya hydroxypropyl methyl cellulose ya hydroxypropyl methyl cellulose kamakhala ndi filimu yabwino kwambiri, yankho lake lamadzimadzi kapena yankho la organic solvent, lopakidwa pa mbale yagalasi, litauma limakhala lopanda utoto, lowonekera bwino komanso lolimba. Lili ndi kukana kwabwino kwa chinyezi ndipo limakhala lolimba kutentha kwambiri. Monga kuwonjezera pulasitiki ya hygroscopic, kumatha kuwonjezera kutalika kwake ndi kusinthasintha, kuti kusinthasintha kukhale bwino, glycerol ndi sorbitol ndi pulasitiki ina ndiyo yoyenera kwambiri. Kuchuluka kwa yankho lonse ndi 2% ~ 3%, mlingo wa pulasitiki ndi 10% ~ 20% ya ether ya cellulose. Ngati kuchuluka kwa pulasitiki kuli kofunikira, kuchepa kwa madzi m'thupi la colloid kumatha kuchitika mu chinyezi chambiri. Mphamvu yolimba ya pulasitiki yowonjezera filimuyo ndi yayikulu kwambiri kuposa yomwe sinawonjezedwe, ndipo imawonjezeka ndi kuchuluka kwa zowonjezera, komanso kuchuluka kwa hygroscopicity ya filimuyo kumawonjezeka ndi kuchuluka kwa pulasitiki.