Kutentha kwa gelation ya cellulose ether HPMC

dziwitsani

Ma cellulose ethers ndi ma polima osungunuka m'madzi anionic opangidwa kuchokera ku cellulose. Ma polima awa ali ndi ntchito zambiri m'mafakitale osiyanasiyana monga chakudya, mankhwala, zodzoladzola, ndi zomangamanga chifukwa cha katundu wawo monga makulidwe, ma gelling, kupanga mafilimu, ndi emulsifying. Chimodzi mwazinthu zofunika kwambiri zama cellulose ethers ndi kutentha kwa gelation (Tg), kutentha komwe polima imadutsa kusintha kwa sol kupita ku gel. Katunduyu ndi wofunikira pakuzindikira momwe ma cellulose ether amagwirira ntchito zosiyanasiyana. M'nkhaniyi, tikambirana za kutentha kwa gelation kwa hydroxypropyl methylcellulose (HPMC), imodzi mwa ma cellulose ether omwe amagwiritsidwa ntchito kwambiri pamakampani.

Thermal gelation kutentha kwa HPMC

HPMC ndi semi-synthetic cellulose ether yomwe imagwiritsidwa ntchito kwambiri pazinthu zosiyanasiyana chifukwa cha mawonekedwe ake apadera. HPMC kwambiri sungunuka m'madzi, kupanga zomveka viscous zothetsera pa otsika ndende. Pamalo okwera kwambiri, HPMC imapanga ma gels omwe amatha kusintha akatenthedwa ndi kuziziritsa. Kutentha kwa kutentha kwa HPMC ndi njira ziwiri zomwe zimapangidwira kupanga micelles yotsatiridwa ndi kuphatikiza kwa micelles kupanga gel network (Chithunzi 1).

Kutentha kwa kutentha kwa gelation kwa HPMC kumadalira zinthu zingapo monga digiri ya m'malo (DS), kulemera kwa maselo, ndende, ndi pH ya yankho. Nthawi zambiri, kukweza kwa DS ndi kulemera kwa mamolekyulu a HPMC, kumapangitsa kuti kutentha kwa matenthedwe kukhale kokwera. Kuchuluka kwa HPMC mu yankho kumakhudzanso Tg, kukwezeka kwa ndende, kukwezeka kwa Tg. PH ya yankho imakhudzanso Tg, ndi njira za acidic zomwe zimapangitsa kuti Tg ikhale yotsika.

Thermal gelation ya HPMC ndi yosinthika ndipo imatha kukhudzidwa ndi zinthu zosiyanasiyana zakunja monga kukameta ubweya, kutentha, ndi ndende ya mchere. Kumeta ubweya kumaphwanya kapangidwe ka gel ndikutsitsa Tg, pomwe kutentha kumapangitsa kuti gel asungunuke ndikutsitsa Tg. Kuonjezera mchere ku yankho kumakhudzanso Tg, ndipo kukhalapo kwa cations monga calcium ndi magnesium kumawonjezera Tg.

Kugwiritsa ntchito Tg HPMC zosiyanasiyana

Thermogelling khalidwe la HPMC akhoza ogwirizana ntchito zosiyanasiyana. Low Tg HPMCs amagwiritsidwa ntchito pofuna kuchedwetsa mwachangu, monga mchere waposachedwa, msuzi ndi supu. HPMC yokhala ndi Tg yokwera imagwiritsidwa ntchito pofuna kuchedwetsa kapena kuchedwetsa nthawi yayitali, monga kupanga makina operekera mankhwala, mapiritsi otulutsa osasunthika, komanso mavalidwe a bala.

M'makampani azakudya, HPMC imagwiritsidwa ntchito ngati thickener, stabilizer ndi gelling agent. Low Tg HPMC imagwiritsidwa ntchito muzakudya pompopompo zomwe zimafuna kuchedwetsa mwachangu kuti zipereke mawonekedwe omwe mukufuna komanso kumva mkamwa. HPMC ndi mkulu Tg ntchito otsika mafuta kufalitsa formulations kumene kuchedwa kapena yaitali gelation amafuna kupewa syneresis ndi kusunga kufalikira dongosolo.

M'makampani opanga mankhwala, HPMC imagwiritsidwa ntchito ngati binder, disintegrant komanso kutulutsa kosalekeza. HPMC yokhala ndi Tg yayikulu imagwiritsidwa ntchito popanga mapiritsi otulutsa nthawi yayitali, pomwe kuchedwetsa kapena kutulutsa nthawi yayitali kumafunika kutulutsa mankhwalawa kwa nthawi yayitali. Low Tg HPMC imagwiritsidwa ntchito popanga mapiritsi osweka pakamwa, pomwe kupasuka mwachangu ndi kutsekemera kumafunika kupereka mkamwa womwe mukufuna komanso kumeza mosavuta.

Pomaliza

Kutentha kwa kutentha kwa gelation kwa HPMC ndi chinthu chofunikira kwambiri chomwe chimatsimikizira machitidwe ake pazinthu zosiyanasiyana. HPMC imatha kusintha Tg yake kudzera mukusintha, kulemera kwa maselo, ndende ndi pH ya yankho kuti igwirizane ndi ntchito zosiyanasiyana. HPMC yokhala ndi Tg yotsika imagwiritsidwa ntchito popanga zinthu zomwe zimafuna kuchedwetsa mwachangu, pomwe HPMC yokhala ndi Tg yayikulu imagwiritsidwa ntchito pofuna kuchedwetsa kapena kuchedwetsa nthawi yayitali. HPMC ndi etha yosunthika komanso yosunthika ya cellulose yomwe ingagwiritsidwe ntchito m'mafakitale osiyanasiyana.