Mphamvu yokhuthala yaether ya celluloseZimadalira: kuchuluka kwa polymerization ya cellulose ether, kuchuluka kwa yankho, kuchuluka kwa shear, kutentha ndi zina. Kapangidwe ka gelling ka yankho ndi kapadera kwa alkyl cellulose ndi zotumphukira zake zosinthidwa. Kapangidwe ka gelation kamagwirizana ndi kuchuluka kwa kusintha, kuchuluka kwa yankho ndi zowonjezera. Pa zotumphukira zosinthidwa za hydroxyalkyl, kapangidwe ka gel kamagwirizananso ndi kuchuluka kwa kusintha kwa hydroxyalkyl. Pa kukhuthala kochepa kwa MC ndi HPMC, yankho la 10%-15% likhoza kukonzedwa, kukhuthala kwapakati kwa MC ndi HPMC kumatha kukonzedwa yankho la 5%-10%, ndipo kukhuthala kwakukulu kwa MC ndi HPMC kumatha kukonzekeretsa yankho la 2%-3%, ndipo nthawi zambiri gulu la kukhuthala kwa cellulose ether limayikidwanso ndi yankho la 1%-2%.
Cellulose ether yokhala ndi mamolekyulu ambiri imakhala ndi mphamvu yokhuthala kwambiri, ndipo ma polima okhala ndi mamolekyulu osiyanasiyana amakhala ndi kukhuthala kosiyana mu yankho lomwelo. Kukhuthala komwe kumayang'aniridwa kumatha kupezeka kokha powonjezera kuchuluka kwa cellulose ether yolemera pang'ono. Kukhuthala kwake sikudalira kwambiri kuchuluka kwa kudulidwa, ndipo kukhuthala kwakukulu kumafika pa kukhuthala komwe kumayang'aniridwa, kumafuna kuwonjezera pang'ono, ndipo kukhuthala kumadalira mphamvu yokhuthala. Chifukwa chake, kuti pakhale kusinthasintha kwina, kuchuluka kwa cellulose ether (kuchuluka kwa yankho) ndi kukhuthala kwa yankho kuyenera kutsimikizika. Kutentha kwa gel ya yankho kumachepanso motsatizana ndi kuwonjezeka kwa kuchuluka kwa yankho, ndi ma gels pa kutentha kwa chipinda atafika pa kuchuluka kwina. Kuchuluka kwa gelling kwa HPMC kumakhala kwakukulu pa kutentha kwa chipinda.
Kugwirizana kungasinthidwenso posankha kukula kwa tinthu tating'onoting'ono ndikusankha ma ether a cellulose okhala ndi madigiri osiyanasiyana osinthira. Chomwe chimatchedwa kusintha ndikuyambitsa kuchuluka kwina kwa magulu a hydroxyalkyl pa kapangidwe ka mafupa a MC. Mwa kusintha ma values osinthira ofanana a ma substituent awiri, ndiko kuti, ma values osinthira ofanana a DS ndi MS a magulu a methoxy ndi hydroxyalkyl omwe nthawi zambiri timanena. Zofunikira zosiyanasiyana za magwiridwe antchito a ether ya cellulose zitha kupezeka posintha ma values osinthira ofanana a ma substituent awiriwa.
Madzi a cellulose ether okhala ndi kukhuthala kwakukulu ali ndi thixotropy yapamwamba, yomwe ndi khalidwe lalikulu la cellulose ether. Madzi a MC polymers nthawi zambiri amakhala ndi pseudoplastic ndi non-thixotropic fluidity pansi pa kutentha kwawo kwa gel, koma Newtonian flow properties pamlingo wotsika wa shear. Pseudoplasticity imawonjezeka ndi kulemera kwa molekyulu kapena kuchuluka kwa cellulose ether, mosasamala kanthu za mtundu wa cholowa m'malo ndi mlingo wa cholowa m'malo. Chifukwa chake, cellulose ethers a kalasi yofanana ya kukhuthala, mosasamala kanthu za MC, HPMC, HEMC, nthawi zonse amawonetsa makhalidwe ofanana a rheological bola ngati kuchuluka ndi kutentha zikusungidwa nthawi zonse. Ma gels omangidwa amapangidwa kutentha kukakwera, ndipo kuyenda kwa thixotropic kwambiri kumachitika. Ma ethers a cellulose okhala ndi kukhuthala kwakukulu komanso kukhuthala kochepa amawonetsa thixotropy ngakhale pansi pa kutentha kwa gel. Katunduyu ndi wothandiza kwambiri pakusintha kwa kulinganiza ndi kutsika pomanga matope omangira.
Apa pakufunika kufotokoza kuti kukhuthala kwaether ya cellulose, kusungidwa kwa madzi kumakhala bwino, koma kukhuthala kwa mamolekyulu a cellulose ether kumakhala kwakukulu, komanso kuchepa kofanana kwa kusungunuka kwake, komwe kumakhudza kwambiri kuchuluka kwa matope ndi magwiridwe antchito omanga. Kukhuthala kwa mamasukidwe kukakhala kwakukulu, kukhuthala kwa matope kumaonekera bwino, koma sikufanana kwenikweni. Kukhuthala kwapakati ndi kotsika, koma ether yosinthidwa ya cellulose ether imakhala ndi magwiridwe antchito abwino pakukweza mphamvu ya kapangidwe ka matope onyowa. Ndi kuwonjezeka kwa kukhuthala, kusungunuka kwa madzi kwa ether ya cellulose kumakula.
Nthawi yotumizira: Epulo-28-2024