I-Methylcellulose (MC) uhlobo lwe-cellulose ether. Ama-compound e-cellulose ether ayizinto ezitholakala ngokuguqulwa kwamakhemikhali kwe-cellulose yemvelo, kanti i-methylcellulose iyi-cellulose derivative ebalulekile eyakhiwe yi-methylating (methyl substitution) ingxenye ye-hydroxyl ye-cellulose. Ngakho-ke, i-methylcellulose akuyona nje i-cellulose derivative, kodwa futhi i-cellulose ether ejwayelekile.
1. Ukulungiswa kwe-methylcellulose
I-Methylcellulose ilungiswa ngokuphendula i-cellulose nge-ejenti ye-methylating (njenge-methyl chloride noma i-dimethyl sulfate) ngaphansi kwezimo ze-alkaline ukuze i-methylate ingxenye ye-hydroxyl ye-cellulose. Lokhu kusabela kwenzeka kakhulu emaqenjini e-hydroxyl ezindaweni ze-C2, C3 kanye ne-C6 ze-cellulose ukuze kwakhiwe i-methylcellulose enamazinga ahlukene okufaka esikhundleni. Inqubo yokusabela imi kanje:
I-Cellulose (i-polysaccharide eyakhiwe ngamayunithi e-glucose) iqala ukusebenza ngaphansi kwezimo ze-alkaline;
Ngemuva kwalokho i-ejenti ye-methylating ifakwa ukuze ibhekane nokusabela kwe-etherification ukuze kutholakale i-methylcellulose.
Le ndlela ingakhiqiza imikhiqizo ye-methylcellulose ene-viscosities ehlukene kanye nezakhiwo zokuncibilika ngokulawula izimo zokusabela kanye nezinga le-methylation.
2. Izakhiwo ze-methylcellulose
I-Methylcellulose inezakhiwo ezilandelayo eziyinhloko:
Ukuncibilika: Ngokungafani ne-cellulose yemvelo, i-methylcellulose ingancibilika emanzini abandayo kodwa hhayi emanzini ashisayo. Lokhu kungenxa yokuthi ukungeniswa kwezinto ezithatha indawo ye-methyl kubhubhisa izibopho ze-hydrogen phakathi kwama-molecule e-cellulose, ngaleyo ndlela kunciphisa ukwakheka kwayo kwekristalu. I-Methylcellulose yakha isisombululo esibonakalayo emanzini futhi ikhombisa izici ze-gelation emazingeni okushisa aphezulu, okungukuthi, isixazululo siyaqina lapho sishiswa futhi siphinde sithole uketshezi ngemva kokupholisa.
Akunabo ubuthi: I-Methylcellulose ayinabo ubuthi futhi ayimuncwa uhlelo lokugaya ukudla lomuntu. Ngakho-ke, ivame ukusetshenziswa ekudleni nasezithasiselweni zemithi njengesithako esiqinisayo, esihlanganisa i-emulsifier kanye nesiqinisi.
Ukulawulwa kwe-Viscosity: I-Methylcellulose inezakhiwo ezinhle zokulawulwa kwe-viscosity, futhi i-viscosity yayo yesisombululo ihlobene nokuhlushwa kwesisombululo kanye nesisindo sama-molecule. Ngokulawula izinga lokufakwa esikhundleni kwe-etherification reaction, imikhiqizo ye-methylcellulose enezinhlobo ezahlukene ze-viscosity ingatholakala.
3. Ukusetshenziswa kwe-methylcellulose
Ngenxa yezakhiwo zayo eziyingqayizivele zomzimba nezamakhemikhali, i-methylcellulose isetshenziswe kabanzi ezimbonini eziningi.
3.1 Imboni yokudla
I-Methylcellulose iyisithako sokudla esivamile esisetshenziswa ekucubungulweni kokudla okuhlukahlukene, ikakhulukazi njengesithako sokujiya, i-emulsifier kanye ne-stabilizer. Njengoba i-methylcellulose ingagcoba ijeli uma ifudunyezwa futhi ibuyisele uketshezi ngemva kokupholisa, ivame ukusetshenziswa ekudleni okuqandisiwe, izinto ezibhakiwe kanye nesobho. Ngaphezu kwalokho, uhlobo lwe-methylcellulose olunama-calorie aphansi luyenza ibe yisithako esibalulekile kwezinye izinhlobo zokudla ezinama-calorie aphansi.
3.2 Izimboni zemithi nezokwelapha
I-Methylcellulose isetshenziswa kabanzi embonini yezemithi, ikakhulukazi ekukhiqizweni kwamaphilisi, njengesithako kanye nesihlanganisi. Ngenxa yekhono layo elihle lokulungisa i-viscosity, ingathuthukisa ngempumelelo amandla okusebenza kanye nezakhiwo zokuqhekeka kwamaphilisi. Ngaphezu kwalokho, i-methylcellulose isetshenziswa futhi njengengxenye yokudabuka kokwenziwa kwezokwelapha amehlo ukwelapha amehlo omile.
3.3 Imboni yokwakha nezinto zokwakha
Phakathi kwezinto zokwakha, i-methylcellulose isetshenziswa kabanzi kusimende, i-gypsum, izimbozo kanye nezinamathiseli njengesithambisi, isibambi samanzi kanye nesithambisi sefilimu. Ngenxa yokugcinwa kwayo kahle kwamanzi, i-methylcellulose ingathuthukisa ukugeleza nokusebenza kwezinto zokwakha futhi igweme ukuvela kwemifantu kanye nezikhala.
3.4 Imboni yezimonyo
I-Methylcellulose isetshenziswa kakhulu embonini yezimonyo njengesithambisi-ndlela kanye nesiqinisi ukusiza ekwakheni ama-emulsion nama-gel ahlala isikhathi eside. Ingathuthukisa umuzwa womkhiqizo futhi ithuthukise umphumela wokuthambisa. Ayinawo umkhuhlane futhi imnene, futhi ifanele isikhumba esibucayi.
4. Ukuqhathaniswa kwe-methylcellulose namanye ama-ether e-cellulose
Ama-cellulose ethers awumndeni omkhulu. Ngaphezu kwe-methylcellulose, kukhona ne-ethyl cellulose (EC), i-hydroxypropyl methylcellulose (HPMC), i-hydroxyethyl cellulose (HEC) nezinye izinhlobo. Umehluko wawo omkhulu usehlobo kanye nezinga lokushintshana kwezinto ezithatha indawo ku-molecule ye-cellulose, okunquma ukuncibilika kwazo, i-viscosity kanye nezindawo zokusetshenziswa.
I-Methylcellulose vs Hydroxypropyl Methylcellulose (HPMC): I-HPMC iyinguqulo ethuthukisiwe ye-methylcellulose. Ngaphezu kwe-methyl substituent, i-hydroxypropyl nayo iyethulwa, okwenza ukuncibilika kwe-HPMC kuhluke kakhulu. I-HPMC ingancibilika ebangeni lokushisa elibanzi, futhi izinga lokushisa layo lokushisa liphakeme kunele-methylcellulose. Ngakho-ke, ezimbonini zezinto zokwakha kanye nezokwelapha, i-HPMC inezinhlobo eziningi zezicelo.
I-Methylcellulose vs Ethyl Cellulose (EC): I-Ethyl cellulose ayincibiliki emanzini, kodwa incibilika ezinyibilikisini eziphilayo. Ivame ukusetshenziswa ezintweni ze-membrane ezikhishwa njalo ukuze kufakwe izinto zokumboza nemithi. I-Methyl cellulose iyancibilika emanzini abandayo futhi isetshenziswa kakhulu njenge-thickener kanye ne-ejenti yokugcina amanzi. Izindawo zayo zokusetshenziswa zihlukile kuneze-ethyl cellulose.
5. Umkhuba wokuthuthukiswa kwama-cellulose ethers
Njengoba isidingo sezinto ezihlala isikhathi eside kanye namakhemikhali aluhlaza sikhula, ama-compound e-cellulose ether, okuhlanganisa ne-methyl cellulose, kancane kancane aba yingxenye ebalulekile yezinto ezinobungani nemvelo. Itholakala emicu yezitshalo zemvelo, ivuseleleka, futhi ingonakaliswa ngokwemvelo emvelweni. Esikhathini esizayo, izindawo zokusetshenziswa kwama-cellulose ethers zingandiswa kakhulu, njengasemandleni amasha, ezakhiweni eziluhlaza kanye ne-biomedicine.
Njengohlobo lwe-cellulose ether, i-methyl cellulose isetshenziswa kabanzi ezimbonini eziningi ngenxa yezakhiwo zayo ezihlukile zomzimba nezamakhemikhali. Ayigcini nje ngokuba nekhono elihle lokuncibilika, ukungabi nobuthi, kanye nekhono elihle lokulungisa i-viscosity, kodwa futhi idlala indima ebalulekile ekudleni, emithini, ekwakheni nasezimonyweni. Esikhathini esizayo, njengoba isidingo sezinto ezinobungani nemvelo sikhula, amathuba okusetshenziswa kwe-methyl cellulose azoba maningi.
Isikhathi sokuthunyelwe: Okthoba-23-2024