Kodi pali kusiyana kotani pakati pa HPMC ndi MC?

MC ndi methyl cellulose, yomwe imapezeka pochiza thonje loyengedwa ndi alkali, pogwiritsa ntchito methyl chloride ngati chothandizira kutenthetsa, ndikupanga cellulose ether kudzera muzochita zingapo. Kawirikawiri, mlingo wa kusintha ndi 1.6 ~ 2.0, ndipo kusungunuka kumasiyananso ndi madigiri osiyanasiyana a kusintha. Ndi ya non-ionic cellulose ether.

(1) Kusunga madzi kwamethyl celluloseZimadalira kuchuluka kwake kowonjezera, kukhuthala, kusalala kwa tinthu tating'onoting'ono ndi kuchuluka kwa kusungunuka. Kawirikawiri, ngati kuchuluka kwa kuwonjezera kuli kwakukulu, kusalala ndi kochepa, ndipo kukhuthala ndi kwakukulu, kuchuluka kwa kusungidwa kwa madzi kumakhala kwakukulu. Pakati pawo, kuchuluka kwa kuwonjezera kumakhudza kwambiri kuchuluka kwa kusungidwa kwa madzi, ndipo kuchuluka kwa kukhuthala sikufanana ndi kuchuluka kwa kusungunuka kwa madzi. Kusungunuka kumadalira makamaka kuchuluka kwa kusintha kwa pamwamba pa tinthu ta cellulose ndi kusalala kwa tinthu tating'onoting'ono. Pakati pa ma cellulose ethers omwe ali pamwambapa, methyl cellulose ndi hydroxypropyl methyl cellulose zimakhala ndi kuchuluka kwa kusungunuka kwa madzi.

(2) Methylcellulose imasungunuka m'madzi ozizira, koma imakhala yovuta kusungunuka m'madzi otentha, ndipo madzi ake amakhala okhazikika kwambiri pa pH = 3 ~ 12. Imagwirizana bwino ndi starch, guar gum, ndi zina zotero. Kutentha kukafika pa kutentha kwa gelation, kumachitika chinthu chotchedwa gelation.

(3) Kusintha kwa kutentha kudzakhudza kwambiri kuchuluka kwa madzi omwe amasungidwa mu methyl cellulose. Nthawi zambiri, kutentha kukakhala kwakukulu, madzi omwe amasungidwa amakhala oipa kwambiri. Ngati kutentha kwa matope kupitirira 40 °C, methyl cellulose yomwe imasungidwa mu matope idzakhala yoipa kwambiri, zomwe zidzakhudza kwambiri kugwira ntchito kwa matope.

(4) Methyl cellulose imakhudza kwambiri kugwira ntchito ndi kumatirira kwa matope. "Kumatirira" apa kumatanthauza kumatira komwe kumakhala pakati pa chida chogwiritsira ntchito cha wantchito ndi khoma, ndiko kuti, kukana kukatira kwa matope. Kumatirirako ndi kwakukulu, kukana kukatira kwa matope ndi kwakukulu, ndipo mphamvu yomwe ogwira ntchito amafunikira pakugwiritsa ntchito matope ndi yayikulu, ndipo kapangidwe ka matope ndi koipa. Kumatirira kwa methylcellulose kuli pamlingo wocheperako muzinthu za cellulose ether.

HPMC ndi hydroxypropyl methyl cellulose, yomwe ndi ether yosakanikirana ya cellulose yosakhala ionic yopangidwa kuchokera ku thonje loyengedwa pambuyo pa mankhwala a alkali, pogwiritsa ntchito propylene oxide ndi methyl chloride ngati zinthu zotenthetsera, komanso kudzera muzochita zingapo. Mlingo wa kusintha nthawi zambiri umakhala 1.2 mpaka 2.0. Katundu wake amasiyana malinga ndi kuchuluka kwa methoxyl ndi kuchuluka kwa hydroxypropyl.

(1) Hydroxypropyl methylcellulose imasungunuka mosavuta m'madzi ozizira, koma imakumana ndi zovuta kusungunuka m'madzi otentha. Koma kutentha kwake kwa gelation m'madzi otentha ndi kwakukulu kwambiri kuposa kwa methyl cellulose. Kusungunuka m'madzi ozizira kumawonjezekanso kwambiri poyerekeza ndi methyl cellulose.

(2) Kukhuthala kwa hydroxypropyl methylcellulose kumagwirizana ndi kukula kwa kulemera kwake kwa mamolekyulu, ndipo kulemera kwa mamolekyulu kukakhala kwakukulu, kukhuthala kumakwera. Kutentha kumakhudzanso kukhuthala kwake, pamene kutentha kukukwera, kukhuthala kumachepa. Koma kukhuthala kwake sikukhudzidwa kwambiri ndi kutentha kwakukulu kuposa methyl cellulose. Yankho lake ndi lokhazikika likasungidwa kutentha kwa chipinda.

(3) Hydroxypropyl methylcellulose ndi yokhazikika ku asidi ndi alkali, ndipo yankho lake lamadzi ndi lokhazikika kwambiri pa pH = 2 ~ 12. Caustic soda ndi madzi a laimu sizikhudza kwambiri magwiridwe ake, koma alkali imatha kufulumizitsa kusungunuka kwake ndikuwonjezera kukhuthala. Hydroxypropyl methylcellulose ndi yokhazikika ku mchere wamba, koma pamene kuchuluka kwa mchere kuli kwakukulu, kukhuthala kwa yankho la hydroxypropyl methylcellulose kumawonjezeka.

(4) Kusunga madzi kwahydroxypropyl methylcelluloseKutengera kuchuluka kwake kowonjezera, kukhuthala, ndi zina zotero. Kuchuluka kwa madzi omwe amasungidwa pansi pa kuchuluka komweko kowonjezera kumakhala kwakukulu kuposa kwa methyl cellulose.

(5) Hydroxypropyl methylcellulose ikhoza kusakanizidwa ndi mankhwala a polymer osungunuka m'madzi kuti apange yankho lofanana komanso lokhuthala kwambiri. Monga polyvinyl alcohol, starch ether, vegetable gum, ndi zina zotero.

(6) Kugwirizana kwa hydroxypropyl methylcellulose ku matope opangidwa ndi matope n'kokwera kuposa kwa methylcellulose.

(7) Hydroxypropyl methylcellulose ili ndi kukana bwino kwa ma enzyme kuposa methylcellulose, ndipo kuthekera kwake kwa enzyme degradation ndi kochepa kuposa kwa methylcellulose.