Methylcellulose (MC) ndi mtundu wa cellulose ether. Ma cellulose ether compounds ndi zotumphukira zomwe zimapezedwa ndi kusintha kwa mankhwala a cellulose yachilengedwe, ndipo methylcellulose ndi gawo lofunikira la cellulose lomwe limapangidwa ndi methylating (methyl substitution) gawo la hydroxyl la cellulose. Chifukwa chake, methylcellulose sikuti imangochokera ku cellulose, komanso ndi ether wapa cellulose.
1. Kukonzekera kwa methylcellulose
Methylcellulose amakonzedwa pochita mapadi ndi methylating agent (monga methyl chloride kapena dimethyl sulfate) pansi pamikhalidwe yamchere kuti methylate gawo la hydroxyl la cellulose. Izi zimachitika makamaka pamagulu a hydroxyl pa C2, C3 ndi C6 malo a cellulose kupanga methylcellulose ndi magawo osiyanasiyana olowa m'malo. The reaction process ndi motere:
Cellulose (polysaccharide yopangidwa ndi mayunitsi a shuga) imayamba kuyendetsedwa pansi pamikhalidwe yamchere;
Kenako methylating agent imayambitsidwa kuti ipange etherification reaction kuti ipeze methylcellulose.
Njirayi imatha kupanga mankhwala a methylcellulose okhala ndi ma viscosities osiyanasiyana ndi zinthu zosungunuka powongolera momwe zinthu zimachitikira komanso kuchuluka kwa methylation.
2. Katundu wa methylcellulose
Methylcellulose ili ndi zinthu zotsatirazi:
Kusungunuka: Mosiyana ndi cellulose yachilengedwe, methylcellulose imatha kusungunuka m'madzi ozizira koma osati m'madzi otentha. Izi ndichifukwa choti kuyambika kwa zolowa m'malo mwa methyl kumawononga zomangira za haidrojeni pakati pa mamolekyu a cellulose, motero kumachepetsa kukongola kwake. Methylcellulose imapanga njira yowonekera m'madzi ndipo imawonetsa mawonekedwe a gelation pa kutentha kwakukulu, ndiko kuti, yankho limakhuthala likatenthedwa ndikubwezeretsanso madzi pambuyo kuzirala.
Non-toxicity: Methylcellulose sipoizoni ndipo sichimatengedwa ndi m'mimba ya munthu. Choncho, nthawi zambiri amagwiritsidwa ntchito muzakudya ndi zowonjezera mankhwala monga thickener, emulsifier ndi stabilizer.
Kuwongolera mamasukidwe akayendedwe: Methylcellulose ali ndi kayendedwe kabwino ka mamasukidwe akayendedwe, ndipo kukhuthala kwake kumagwirizana ndi ndende ya yankho ndi kulemera kwa maselo. Poyang'anira kuchuluka kwa kulowetsedwa m'malo mwa etherification, mankhwala a methylcellulose okhala ndi ma viscosity osiyanasiyana amatha kupezeka.
3. Kugwiritsa ntchito methylcellulose
Chifukwa cha mawonekedwe ake apadera akuthupi ndi mankhwala, methylcellulose yakhala ikugwiritsidwa ntchito kwambiri m'mafakitale ambiri.
3.1 Makampani azakudya
Methylcellulose ndi chowonjezera chazakudya chomwe chimagwiritsidwa ntchito popanga zakudya zosiyanasiyana, makamaka ngati thickener, emulsifier ndi stabilizer. Popeza methylcellulose imatha kupaka mafuta ikatenthedwa ndikubwezeretsa madzi pambuyo kuzirala, imagwiritsidwa ntchito muzakudya zozizira, zophika ndi supu. Kuonjezera apo, chikhalidwe chochepa cha calorie cha methylcellulose chimapangitsa kuti chikhale chofunika kwambiri pazakudya zamagulu ochepa.
3.2 Makampani opanga mankhwala ndi zamankhwala
Methylcellulose amagwiritsidwa ntchito kwambiri m'makampani opanga mankhwala, makamaka pakupanga mapiritsi, monga chothandizira komanso chomangira. Chifukwa chake chabwino mamasukidwe akayendedwe kusintha luso, akhoza bwino kusintha mawotchi mphamvu ndi azingokhala katundu mapiritsi. Kuphatikiza apo, methylcellulose imagwiritsidwanso ntchito ngati gawo lopangira misozi mu ophthalmology pochiza maso owuma.
3.3 Makampani omanga ndi zida
Pakati pa zida zomangira, methylcellulose imagwiritsidwa ntchito kwambiri mu simenti, gypsum, zokutira ndi zomatira ngati thickener, chosungira madzi komanso filimu yakale. Chifukwa cha kusungirako bwino kwa madzi, methylcellulose imatha kupititsa patsogolo kutulutsa madzi komanso kugwira ntchito kwa zida zomangira ndikupewa kutulutsa ming'alu ndi voids.
3.4 Makampani opanga zodzikongoletsera
Methylcellulose amagwiritsidwanso ntchito popanga zodzikongoletsera ngati thickener ndi stabilizer kuthandiza kupanga emulsion yaitali ndi gel osakaniza. Ikhoza kusintha kumverera kwa mankhwala ndi kupititsa patsogolo moisturizing kwenikweni. Ndi hypoallergenic komanso yofatsa, ndipo ndi yoyenera khungu lovuta.
4. Kuyerekeza methylcellulose ndi ma cellulose ethers ena
Ma cellulose ethers ndi banja lalikulu. Kuphatikiza pa methylcellulose, palinso ethyl cellulose (EC), hydroxypropyl methylcellulose (HPMC), hydroxyethyl cellulose (HEC) ndi mitundu ina. Kusiyana kwawo kwakukulu kwagona mu mtundu ndi digiri ya m'malo m'malo pa cellulose molekyulu, amene amatsimikiza awo solubility, mamasukidwe akayendedwe ndi ntchito madera.
Methylcellulose vs Hydroxypropyl Methylcellulose (HPMC): HPMC ndi mtundu wabwino wa methylcellulose. Kuphatikiza pa methyl substituent, hydroxypropyl imayambitsidwanso, zomwe zimapangitsa kusungunuka kwa HPMC kukhala kosiyanasiyana. HPMC ikhoza kusungunuka mu kutentha kwakukulu, ndipo kutentha kwake kwa gelation kumakhala kopambana kuposa methylcellulose. Chifukwa chake, muzomangamanga ndi mafakitale opanga mankhwala, HPMC ili ndi ntchito zambiri.
Methylcellulose vs Ethyl Cellulose (EC): Ethyl cellulose ndi osasungunuka m'madzi, koma sungunuka mu organic solvents. Nthawi zambiri amagwiritsidwa ntchito popanga zida zomangira zomangira ndi mankhwala. Methyl cellulose amasungunuka m'madzi ozizira ndipo amagwiritsidwa ntchito makamaka ngati thickener ndi kusunga madzi. Madera omwe amagwiritsidwa ntchito ndi osiyana ndi a ethyl cellulose.
5. Kukula kwa ma cellulose ethers
Pakuchulukirachulukira kwa zida zokhazikika ndi mankhwala obiriwira, ma cellulose ether, kuphatikiza methyl cellulose, pang'onopang'ono akukhala gawo lofunikira pazachilengedwe. Zimachokera ku ulusi wachilengedwe wa zomera, zimangowonjezedwanso, ndipo zimatha kuwonongeka mwachilengedwe m'chilengedwe. M'tsogolomu, madera ogwiritsira ntchito ma cellulose ethers akhoza kukulitsidwanso, monga mphamvu zatsopano, nyumba zobiriwira ndi biomedicine.
Monga mtundu wa cellulose ether, methyl cellulose imagwiritsidwa ntchito kwambiri m'mafakitale ambiri chifukwa cha mawonekedwe ake apadera akuthupi ndi mankhwala. Sizingokhala ndi kusungunuka kwabwino, kusakhala ndi kawopsedwe, komanso luso losintha ma viscosity, komanso limagwira ntchito yofunika kwambiri pazakudya, mankhwala, zomangamanga ndi zodzoladzola. M'tsogolomu, ndi kuchuluka kwa kufunikira kwa zida zokomera chilengedwe, chiyembekezo chogwiritsa ntchito methyl cellulose chidzakhala chokulirapo.
Nthawi yotumiza: Oct-23-2024