Ukuchithwa kwe-cellulose ethers kunokuba yinkqubo enzima ngenxa yesakhiwo sabo sekhemikhali esiyingqayizivele kunye neempawu. I-cellulose ethers ziipolima ezinyibilikayo emanzini ziphuma kwi-cellulose, i-polysaccharide eyenzeka ngokwemvelo efumaneka kwiindonga zeeseli zesityalo. Zisetyenziswa kakhulu kumashishini ahlukeneyo afana namayeza, ukutya, amalaphu, kunye nokwakha ngenxa yendlela egqwesileyo yokwenza ifilimu, ukutyeba, ukubopha, kunye nokuzinzisa iipropathi.
1. Ukuqonda iCellulose Ethers:
I-cellulose ethers ziphuma kwi-cellulose, apho amaqela e-hydroxyl athi ngokuyinxenye okanye afakwe ngokupheleleyo endaweni yamaqela e-ether. Iintlobo eziqhelekileyo ziquka i-methyl cellulose (MC), i-hydroxypropyl cellulose (HPC), i-hydroxyethyl cellulose (HEC), kunye ne-carboxymethyl cellulose (CMC). Uhlobo ngalunye luneempawu ezizodwa ngokuxhomekeke kwiqondo kunye nohlobo lokutshintshwa.
2. Imiba echaphazela ukunyibilika:
Izinto ezininzi zinefuthe ekunyibilikeni kwe-cellulose ethers:
I-Degree of Substitution (DS): I-DS ephezulu iphucula ngokubanzi ukunyibilika njengoko inyusa i-hydrophilicity ye-polymer.
Ubunzima beMolekyuli: I-ethers ephezulu ye-molecular weight cellulose inokufuna ixesha elingakumbi okanye amandla okutshatyalaliswa.
Iipropati zokunyibilikisa: Izinyibilikisi ezinepolarity ephezulu kunye nesakhono sokudibanisa i-hydrogen, njengamanzi kunye nezinyibilikisi zendalo eziphuma kwincam yomhlaba, zisebenza ngokubanzi ekunyibilikiseni i-cellulose ethers.
Ubushushu: Ukunyusa amaqondo obushushu kunokonyusa ukunyibilika ngokunyusa amandla e-kinetic yeemolekyuli.
Ukuphazamiseka: Ukuphazamiseka komatshini kunokuncedisa ukunyibilika ngokwandisa unxibelelwano phakathi kwe-solvent kunye ne-polymer.
pH: Kwezinye ii-ether ze-cellulose ezifana ne-CMC, i-pH inokuchaphazela kakhulu ukunyibilika ngenxa yamaqela ayo e-carboxymethyl.
3. Izinyibilikisi zoNyibiliko:
Amanzi: Ii-ethers ezininzi ze-cellulose zinyibilika ngokulula emanzini, nto leyo eyenza ibe yeyona nto iphambili yokunyibilikisa kwizicelo ezininzi.
Utywala: I-Ethanol, i-methanol, kunye ne-isopropanol zisetyenziswa ngokuqhelekileyo i-co-solvents ukuphucula ukunyibilika kwe-cellulose ethers, ngakumbi abo banokunyibilika okuncinci kwamanzi.
I-Organic Solvents: I-Dimethyl sulfoxide (i-DMSO), i-dimethylformamide (i-DMF), kunye ne-N-methylpyrrolidone (NMP) zihlala zisetyenziselwa izicelo ezizodwa apho ukunyibilika okuphezulu kuyadingeka.
4. IiNdlela zokuSebenza:
Ukuvuselela Okulula: Kwiinkqubo ezininzi, ukuvuselela nje ii-ether zeselulosi kwisinyibilikisi esifanelekileyo kwiqondo lobushushu elisezantsi kwanele ukunyibilika. Nangona kunjalo, amaqondo obushushu aphezulu kunye namaxesha amade okushukuma anokuba yimfuneko ukupheliswa ngokupheleleyo.
Ukufudumeza: Ukufudumeza i-solvent okanye umxube we-solvent-polymer unokukhawulezisa ukuchithwa, ngakumbi kwi-ethers ephezulu ye-molecular weight cellulose okanye ezo zine-solubility ephantsi.
I-Ultrasonication: Ukuxhatshazwa kwe-Ultrasonic kunokuphucula ukuchithwa ngokudala iibhubhu ze-cavitation ezikhuthaza ukuhlukana kwee-polymer aggregates kunye nokuphucula ukungena kwe-solvent.
Ukusetyenziswa kwe-Co-solvents: Ukudibanisa amanzi kunye notywala okanye ezinye izinyibilikisi ze-polar organic zingaphucula ukunyibilika, ngakumbi kwi-cellulose ethers kunye ne-solubility encinci yamanzi.
5. Iingqwalasela eziSebenzayo:
Ubungakanani beNcam: I-ethers ye-cellulose engumgubo ocolekileyo inyibilika ngokulula ngakumbi kunamasuntswana amakhulu ngenxa yokwanda kwendawo.
Ukulungiswa kwezisombululo: Ukulungiselela izisombululo ze-cellulose ether ngendlela ehamba phambili, njengokusasaza i-polymer kwinxalenye ye-solvent ngaphambi kokuba ungeze enye, inokunceda ukukhusela i-clumping kunye nokuqinisekisa ukuchithwa okufanayo.
Ukulungiswa kwe-pH: Kwi-cellulose ethers enovelwano kwi-pH, ukulungelelanisa i-pH ye-solvent kunokuphucula ukunyibilika nokuzinza.
Ukhuseleko: Ezinye izinyibilikisi ezisetyenziselwa ukunyibilikisa i-cellulose ethers zinokubeka umngcipheko kwimpilo nakukhuseleko. Kufuneka kusetyenziswe umoya ofanelekileyo kunye nezixhobo zokuzikhusela xa uphethe ezi zinyibilikisi.
6. Iingqwalasela ezingqamene nesicelo:
Amachiza: I-ethers ye-cellulose isetyenziswa ngokubanzi kwimixube yamachiza ukuze kukhululwe okulawulwayo, ukubopha, kunye nokuqina. Ukukhethwa kwe-solvent kunye nendlela yokuchithwa kuxhomekeke kwiimfuno ezithile zokuqulunqa.
Ukutya: Kwizinto ezisetyenziswa ekutyeni, i-cellulose ethers isetyenziswa njengezinto ezityebisayo, zizinzisi, kunye nezithatha indawo yamafutha. Izinyibilikisi ezihambelana nemimiselo yokutya kufuneka zisetyenziswe, kwaye iimeko zokuchithwa kufuneka ziphuculwe ukugcina umgangatho wemveliso.
Ulwakhiwo: I-cellulose ethers isetyenziswa kwizinto zokwakha ezifana nodaka, iigrouts, kunye nezinto zokuncamathelisa. Ukhetho lwe-solvent kunye neemeko zokuchithwa zibalulekile ekufezekiseni i-viscosity efunwayo kunye neempawu zokusebenza.
7. Izalathiso zexesha elizayo:
Uphando kwi-solvents ezinoveli kunye nobuchule bokutshatyalaliswa buyaqhubeka nokuqhubela phambili intsimi ye-cellulose ether chemistry. Izinyibilikisi eziluhlaza, ezifana ne-CO2 ephezulu kunye nolwelo lwe-ionic, zibonelela ngeendlela ezinokuthi zibe kho ezinempembelelo encitshisiweyo yokusingqongileyo. Ukongeza, ukuqhubela phambili kubunjineli bepolymer kunye ne-nanotechnology kunokukhokelela kuphuhliso lwe-cellulose ethers kunye ne-solubility ephuculweyo kunye neempawu zokusebenza.
ukuchithwa kwe-cellulose ethers yinkqubo eneenkalo ezininzi eziphenjelelwa zizinto ezahlukeneyo ezifana nesakhiwo se-polymer, iipropati ze-solvent, kunye nobuchule bokuchithwa. Ukuqonda ezi zinto kunye nokukhetha izinyibilikisi ezifanelekileyo kunye neendlela zibalulekile ekufezekiseni ukunyibilika okusebenzayo kunye nokuphucula ukusebenza kwe-cellulose ethers kwizicelo ezahlukeneyo.
Ixesha lokuposa: Apr-10-2024