Ukuvelisa i-hydroxyethyl cellulose (HEC) ibandakanya uchungechunge lwee-chemical reactions ukuguqula i-cellulose, i-polymer yendalo evela kwizityalo. I-HEC isetyenziswa kakhulu kumashishini ahlukeneyo, kubandakanywa amayeza, izithambiso, ukutya, kunye nokwakhiwa, ngenxa yokuqina kwayo, ukuzinzisa, kunye neempawu zokugcina amanzi.
Intshayelelo ngeHydroxyethyl Cellulose (HEC)
I-Hydroxyethyl cellulose (HEC) i-non-ionic, i-polymer e-soluble yamanzi ephuma kwi-cellulose ngokuguqulwa kweekhemikhali. Isetyenziswa ngokubanzi njenge-thickening, gelling, kunye ne-ejenti yokuzinzisa kumashishini ahlukeneyo.
Iimpahla ezingekasilwa
I-Cellulose: Eyona nto iphambili kwimveliso ye-HEC. I-Cellulose inokufunyanwa kwizinto ezahlukeneyo ezisekwe kwizityalo ezifana ne-pulp yomthi, umqhaphu, okanye iintsalela zezolimo.
I-Ethylene Oxide (EO): Ikhemikhali engundoqo esetyenziselwa ukwazisa amaqela e-hydroxyethyl kwi-cellulose backbone.
I-Alkali: Ngokuqhelekileyo i-sodium hydroxide (NaOH) okanye i-potassium hydroxide (KOH) isetyenziswe njenge-catalyst kwi-reaction.
Inkqubo yokuVelisa
Ukuveliswa kwe-HEC kubandakanya i-etherification ye-cellulose kunye ne-ethylene oxide phantsi kweemeko ze-alkaline.
La manyathelo alandelayo achaza inkqubo:
1. Unyango lwangaphambili lweCellulose
I-cellulose ihlanjululwa kuqala ukuze isuse ukungcola njenge-lignin, i-hemicellulose, kunye nezinye izinto ezixutywayo. I-cellulose ehlambulukileyo yomiswa kumxholo othile wokufuma.
2. Etherification Reaction
Ukulungiswa kwesisombululo se-Alkaline: Isisombululo samanzi se-sodium hydroxide (NaOH) okanye i-potassium hydroxide (KOH) ilungiselelwe. Ukugxininiswa kwesisombululo sealkali kubalulekile kwaye kufuneka kuphuculwe ngokusekelwe kwiqondo elifunwayo lokutshintshwa (DS) kwemveliso yokugqibela.
Ukuseta iRection: Iselulosi ecociweyo isasazwe kwisisombululo sealkali. Umxube ufudunyezwe kwiqondo lokushisa elithile, ngokuqhelekileyo malunga ne-50-70 ° C, ukuqinisekisa ukuba i-cellulose idumbile ngokupheleleyo kwaye ifikeleleke kwi-reaction.
Ukongezwa kwe-Ethylene Oxide (EO): I-Ethylene oxide (EO) yongezwa ngokukhawuleza kwisitya sokusabela ngelixa igcina ubushushu kwaye ivuselela ngokuqhubekayo. Indlela abasabela ngayo iyingozi kakhulu, ngoko ke ukulawula ubushushu kubalulekile ukunqanda ukufudumeza ngokugqithiseleyo.
Ukujongwa kweRection: Inkqubela phambili yempendulo ijongwa ngokuhlalutya iisampulu ngamaxesha aqhelekileyo. Ubuchwephesha obufana neFourier-transform infrared spectroscopy (FTIR) bunokusetyenziswa ukumisela iqondo lokutshintshwa (DS) kwamaqela e-hydroxyethyl kumqolo wecellulose.
I-Neutralization kunye nokuhlamba: Emva kokuba i-DS efunwayo ifezekisiwe, ukusabela kucinywa ngokunciphisa isisombululo se-alkaline nge-asidi, ngokuqhelekileyo i-acetic acid. I-HEC enesiphumo iye ihlanjwe ngocoselelo ngamanzi ukuze kususwe naziphi na ii-reagents ezingachatshazelwanga kunye nokungcola.
3. Ukuhlanjululwa kunye nokomisa
I-HEC ehlanjiweyo ihlanjululwa ngakumbi ngokucoca okanye i-centrifugation ukususa nakuphi na ukungcola okuseleyo. I-HEC ecociweyo iye yomiswa kumxholo othile wokufuma ukufumana imveliso yokugqibela.
Ulawulo lwemeko
Ukulawulwa komgangatho kubalulekile kuyo yonke inkqubo ye-HEC yokuvelisa ukuqinisekisa ukuhambelana kunye nokucoceka kwemveliso yokugqibela. Iiparamitha eziphambili zokubeka iliso ziquka:
Isidanga sokutshintshwa (DS)
Viscosity
Umxholo wokufuma
pH
Ubunyulu (ukungabikho kokungcola)
Iindlela zokuhlalutya ezifana ne-FTIR, imilinganiselo ye-viscosity, kunye nohlalutyo olusisiseko ziqhele ukusetyenziswa kulawulo lomgangatho.
Ukusetyenziswa kwe-Hydroxyethyl Cellulose (HEC)
I-HEC ifumana izicelo kumashishini ahlukeneyo ngenxa yeempawu zayo eziguquguqukayo:
I-Pharmaceuticals: Isetyenziswa njenge-ejenti ejiyileyo ekumisweni ngomlomo, kwimixube yezihloko, kunye neenkqubo zokuhanjiswa kweziyobisi ezilawulwayo.
Izithambiso: Idla ngokusetyenziswa kwiikhrimu, izinto zokuthambisa, kunye neshampu njengento etyebisayo nezinzisa.
Ukutya: Yongezwa kwiimveliso zokutya njenge-ejenti yokuqina kunye ne-gelling, i-emulsifier, kunye ne-stabilizer.
Ulwakhiwo: Isetyenziselwa udaka olusekwe kwisamente kunye neegrouts ukuphucula ukusebenza kunye nokugcinwa kwamanzi.
Iingqwalasela zokusiNgqongileyo noKhuseleko
Impembelelo yokusingqongileyo: Ukuveliswa kwe-HEC kubandakanya ukusetyenziswa kweekhemikhali ezifana ne-ethylene oxide kunye ne-alkalis, enokuthi ibe nefuthe lendalo. Ulawulo olululo lwenkunkuma kunye nokuthotyelwa kwemimiselo kubalulekile ukunciphisa impembelelo yokusingqongileyo.
Ukhuseleko: I-ethylene oxide yigesi esebenza kakhulu kwaye enokutsha, ebeka imingcipheko yokhuseleko ngexesha lokuphatha kunye nokugcinwa. Ukungena komoya okwaneleyo, izixhobo zokuzikhusela (i-PPE), kunye nemigaqo yokhuseleko iyafuneka ukuze kuqinisekiswe ukhuseleko lwabasebenzi.
I-Hydroxyethyl cellulose (HEC) yipolymer exabisekileyo enezicelo ezahlukeneyo kumashishini ukusuka kumayeza ukuya kulwakhiwo. Ukuveliswa kwayo kubandakanya i-etherification ye-cellulose kunye ne-ethylene oxide phantsi kweemeko ze-alkaline. Amanyathelo olawulo lomgangatho abalulekile ukuqinisekisa ukuhambelana kunye nokucoceka kwemveliso yokugqibela. Iingqwalasela zokusingqongileyo kunye nokhuseleko kufuneka nazo ziqwalaselwe kuyo yonke inkqubo yemveliso. Ngokulandela iinkqubo ezifanelekileyo kunye neeprothokholi, i-HEC inokuveliswa ngokufanelekileyo ngelixa inciphisa impembelelo yokusingqongileyo kunye nokuqinisekisa ukhuseleko lwabasebenzi.
Esi sikhokelo esibanzi sibandakanya inkqubo yokuvelisa i-hydroxyethyl cellulose (HEC) ngokweenkcukacha, ukusuka kwizinto eziluhlaza ukuya kulawulo lomgangatho kunye nokusetyenziswa, ukubonelela ngokuqonda ngokucokisekileyo inkqubo yokuvelisa i-polymer ebalulekileyo.
Ixesha lokuposa: Apr-10-2024