I-Cellulose ethers izinhlobonhlobo zama-polymers ancibilika emanzini atholakala ku-cellulose, i-polymer yemvelo etholakala ezindongeni zamaseli ezitshalo. Lawa ma-ether anezinto eziyingqayizivele ezifana nokujiya, ukuqiniswa, ukwenza ifilimu, nokugcinwa kwamanzi, futhi asetshenziswa kakhulu ezimbonini ezihlukahlukene ezifana nemithi, ukudla, izimonyo, nezokwakha. Phakathi kwama-cellulose ethers, i-hydroxyethyl cellulose (HEC) ne-hydroxypropyl methylcellulose (HPMC) yizinto ezimbili ezibalulekile eziphuma kuzo, ngayinye enezakhiwo ezihlukene kanye nezicelo.
1. Isingeniso se-cellulose ethers
A. Isakhiwo SeCellulose Nokunye Okususelwe
Ukubuka konke kwe-cellulose:
I-Cellulose iyi-polymer eqondile eyakhiwe amayunithi e-glucose axhunywe ngamabhondi e-β-1,4-glycosidic.
Icebile ezindongeni zamaseli ezitshalo futhi inikeza ukwesekwa kwesakhiwo kanye nokuqina ezicubu zezitshalo.
Okuphuma kokuphuma kwe-cellulose ether:
Ama-cellulose ethers atholakala ku-cellulose ngokuguqulwa kwamakhemikhali.
I-Ethers yethulwa ukuze kwandiswe ukunyibilika futhi iguqule izakhiwo zokusebenza.
2. I-Hydroxyethylcellulose (HEC)
A. Isakhiwo kanye nokuhlanganisa
Isakhiwo samakhemikhali:
I-HEC itholakala ngokufakwa kwe-cellulose nge-ethylene oxide.
Amaqembu e-Hydroxyethyl athatha indawo yamaqembu e-hydroxyl esakhiweni se-cellulose.
I-Degree of substitution (DS):
I-DS ibhekisela enanini eliyisilinganiso lamaqembu e-hydroxyethyl ngeyunithi ngayinye ye-anhydroglucose.
Ithinta i-solubility, viscosity nezinye izakhiwo ze-HEC.
B. Imvelo
Ukunyibilika:
I-HEC iyancibilika emanzini abandayo nashisayo, ihlinzeka ngokuguquguquka kwesicelo.
I-Viscosity:
Njengesilungisi se-rheology, sithinta ukushuba nokugeleza kwesixazululo.
Iyahlukahluka nge-DS, ukugxila kanye nezinga lokushisa.
Ukwakhiwa kwefilimu:
Yakha ifilimu esobala ngokunamathela okuhle kakhulu.
C. Isicelo
umuthi:
Isetshenziswa njenge-thickener kumafomu omthamo we-liquid.
Thuthukisa i-viscosity nokuzinza kwamaconsi iso.
Amapende nama-Coatings:
Ithuthukisa i-viscosity futhi inikeza izakhiwo ezinhle kakhulu zokuqina.
Thuthukisa ukunamathela kopende nokuzinza.
Imikhiqizo yokunakekelwa komuntu siqu:
Kutholakala kuma-shampoos, okhilimu kanye nezigcobo njengesithako esiqinisayo nesiqinisayo.
Inikeza ukuthungwa okubushelelezi kuzimonyo.
3. I-Hydroxypropylmethylcellulose (HPMC)
A. Isakhiwo kanye nokuhlanganisa
Isakhiwo samakhemikhali:
I-HPMC ihlanganiswa ngokushintsha amaqembu e-hydroxyl ngamaqembu e-methoxy nawe-hydroxypropyl.
I-Etherification kwenzeka ngokusabela nge-propylene oxide ne-methyl chloride.
I-Methoxy ne-hydroxypropyl esikhundleni:
Iqembu le-methoxy lifaka isandla ekuncibilikeni, kuyilapho iqembu le-hydroxypropyl lithinta i-viscosity.
B. Imvelo
I-Thermal Gelation:
Ibonisa i-gelation ye-thermal ehlehliswayo, yakha ama-gel emazingeni okushisa aphezulu.
Ingasetshenziselwa ukukhishwa okulawulwayo amalungiselelo emithi.
Ukugcinwa kwamanzi:
Umthamo omuhle kakhulu wokugcina amanzi, okwenza afaneleke izicelo zokwakha.
Umsebenzi ongaphezulu:
Ibonisa izici ezifana ne-surfactant ukusiza ukuzinzisa ama-emulsion.
C. Isicelo
Imboni yezokwakha:
Isetshenziswa njenge-ejenti yokugcina amanzi odakeni olusekelwe kusimende.
Ithuthukisa ukusebenza kanye nokunamathela kwezinamathiselo zamathayela.
umuthi:
Okuvame ukusetshenziswa ekulungiseleleni imithi yomlomo kanye ne-topical.
Kwenza kube lula ukukhululwa kwezidakamizwa okulawulwayo ngenxa yekhono layo lokwenza ijeli.
imboni yokudla:
Isebenza njenge-thickener kanye ne-stabilizer ekudleni.
Inikeza ukuthungwa okuthuthukisiwe nokuzwakala komlomo ezinhlelweni ezithile.
4. Ukuhlaziya okuqhathanisayo
A. Umehluko ekuhlanganiseni
I-HEC ne-HPMC synthesis:
I-HEC ikhiqizwa ngokusabela kwe-cellulose nge-ethylene oxide.
Ukuhlanganiswa kwe-HPMC kufaka ukufaka esikhundleni okuphindwe kabili kwamaqembu e-methoxy ne-hydroxypropyl.
B. Umehluko wokusebenza
I-Solubility kanye ne-Viscosity:
I-HEC iyancibilika emanzini abandayo nashisayo, kuyilapho ukunyibilika kwe-HPMC kuthintwa okuqukethwe kweqembu le-methoxy.
I-HEC ngokuvamile ibonisa i-viscosity ephansi uma iqhathaniswa ne-HPMC.
Ukuziphatha kwe-gel:
Ngokungafani ne-HPMC, eyakha ama-gel aguquguqukayo, i-HEC ayitholi i-gelation eshisayo.
C. Umehluko ekusetshenzisweni
Ukugcinwa kwamanzi:
I-HPMC ikhethwa ezinhlelweni zokwakha ngenxa yezindawo zayo ezinhle kakhulu zokugcina amanzi.
Amandla okwenza ifilimu:
I-HEC yenza amafilimu acacile anokunamathela okuhle, okwenza afaneleke izinhlelo zokusebenza ezithile lapho ukwakheka kwefilimu kubalulekile.
5 Isiphetho
Kafushane, i-hydroxyethyl cellulose (HEC) ne-hydroxypropyl methylcellulose (HPMC) ama-cellulose ether abalulekile anezakhiwo eziyingqayizivele kanye nezicelo. Izakhiwo zabo zamakhemikhali eziyingqayizivele, izindlela zokuhlanganisa, kanye nezakhiwo ezisebenzayo zibenza basebenzise izinto ezihlukahlukene ezimbonini ezihlukahlukene. Ukuqonda umehluko phakathi kwe-HEC ne-HPMC kungakusiza wenze isinqumo unolwazi lapho ukhetha i-cellulose ether efanele yohlelo lokusebenza oluthile, kungakhathaliseki ukuthi kwezemithi, ukwakhiwa, upende noma imikhiqizo yokunakekelwa komuntu siqu. Njengoba ubuchwepheshe buthuthuka ngesayensi, ucwaningo olwengeziwe lungase lwembule ukusetshenziswa nokulungiswa okwengeziwe, ngaleyo ndlela kuthuthukise ukusetshenziswa kwalawa ma-cellulose ether emikhakheni ehlukene.
Isikhathi sokuthumela: Dec-11-2023