I-ether ye-cellulose iya kulibazisa i-hydration ye-cement kwii-degrees ezihlukeneyo, ezibonakaliswa ngokulibazisa ukubunjwa kwe-ettringite, i-gel ye-CSH kunye ne-calcium hydroxide. Okwangoku, indlela ye-cellulose ether yokulibazisa i-cement hydration ikakhulu ibandakanya ukucinga kwentshukumo ye-ion ethintelweyo, ukuthotywa kwe-alkali kunye ne-adsorption.
1. I-hypothesis yentshukumo ye-ion ethintelweyo
Kucingelwa ukuba i-cellulose ethers yandisa i-viscosity yesisombululo se-pore, ithintela isantya sokuhamba kwe-ion, ngaloo ndlela ilibazisa i-cement hydration. Nangona kunjalo, kolu vavanyo, i-ether ye-cellulose ene-viscosity ephantsi inamandla amakhulu okulibazisa i-cement hydration, ngoko ke le ngcamango ayibambeli. Enyanisweni, ixesha lokuhamba kwe-ion okanye ukufuduka lifutshane kakhulu, elingenakuqhathaniswa nexesha lokulibaziseka kwe-cement hydration.
2. Ukuthotywa kwealkaline
Iipolysaccharides zidla ngokuthotywa ngokulula phantsi kweemeko zealkaline ukuze zenze i-hydroxycarboxylic acids ezilibazisa ukuhanjiswa kwesamente. Ngoko ke, isizathu sokuba i-cellulose ether ilibazise ukuchithwa kwe-samente inokuba ithoba kwi-alkaline sement slurry ukwenza i-hydroxycarboxylic acids, kodwa uphando lufumene ukuba i-ether ye-Cellulose izinzile kakhulu phantsi kweemeko ze-alkaline, iyancipha nje kancinci, kunye neemveliso ezithotyiweyo azinampembelelo. ekulibazisekeni kwesamente hydration.
3. I-Adsorption
I-Adsorption inokuba sesona sizathu sokuba kutheni i-cellulose ether ilibazisa ukuhanjiswa kwesamente. Izongezo ezininzi zezinto eziphilayo ziya kubhengezwa kwiincinci ze-samente kunye neemveliso ze-hydration, ukukhusela ukuchithwa kweengqungquthela ze-samente kunye ne-crystallization yeemveliso ze-hydration, ngaloo ndlela ukulibazisa ukuhanjiswa kunye nokusekwa kwe-samente. Kwafunyaniswa ukuba i-cellulose ether ibhengezwa ngokulula kwi-calcium hydroxide, C. S. Umphezulu weemveliso ze-hydration ezifana ne-H gel kunye ne-calcium aluminate hydrate, kodwa akukho lula ukubhengezwa ngesigaba se-ettringite kunye ne-unhydrated. Ngaphezu koko, ngokumalunga ne-cellulose ether, umthamo we-adsorption we-HEC womelele kune-MC, kwaye ungaphantsi komxholo we-hydroxyethyl kwi-HEC okanye i-hydroxypropyl kwi-HPMC, ukuqina komthamo we-adsorption: ngokubhekiselele kwimveliso ye-hydration, i-hydrogen. Umthamo we-adsorption we-calcium oxide C. S. Umthamo we-adsorption we-H womelele. Uhlalutyo olongezelelweyo lukwabonisa ukuba umthamo we-adsorption yeemveliso ze-hydration kunye ne-ether cellulose inobudlelwane obuhambelanayo kunye nokulibaziseka kwe-samente hydration: i-adsorption yomelele, i-adsorption icacile, kodwa i-adsorption ye-ettringite kwi-ether cellulose ibuthathaka, kodwa ukwakheka kwayo. yalibaziseka kakhulu. Uphononongo luye lwabonisa ukuba i-cellulose ether ine-adsorption enamandla kwi-tricalcium silicate kunye neemveliso zayo ze-hydration, ngaloo ndlela ilibazisa kakhulu i-hydration yesigaba se-silicate, kwaye ine-adsorption ephantsi kwi-ettringite, kodwa ukubunjwa kwe-ettringite kuthintelwe. Ngokucacileyo ukulibaziseka, oku kungenxa yokuba ukulibaziseka ukubunjwa kwe-ettringite kuchaphazeleka kwibhalansi ye-Ca2 + kwisisombululo, esikukuqhubekeka kokulibaziseka kwe-silicate hydration ye-cellulose ether.
Kwiziphumo zovavanyo, ukukwazi ukubuyiswa kwe-HEC kunamandla kunoko kwe-MC, kwaye ukukwazi kwe-cellulose ether ukulibazisa ukubunjwa kwe-calcium hydroxide yomelele kune-C. S. Ikhono le-H gel kunye ne-ettringite linamandla, elinobudlelwane obuhambelanayo kunye nomthamo we-adsorption we-cellulose ether kunye neemveliso ze-cement hydration. Kwakhona kuqinisekiswa ukuba i-adsorption ingaba sesona sizathu sokuba kutheni i-cellulose ether ilibazise i-cement hydration, kunye ne-cellulose ether kunye neemveliso ze-cement hydration zinobudlelwane obuhambelanayo. Okukhona ukomelela komthamo we-adsorption yeemveliso zesamente zokugalela amanzi, kokukhona kucaca ngakumbi ukwakheka kweemveliso ezilibazisekayo zokugalela amanzi. Iziphumo zovavanyo zangaphambili zibonisa ukuba i-cellulose ethers ezahlukeneyo zineempembelelo ezahlukeneyo kwi-Portland cement hydration ukulibaziseka, kunye ne-ether ye-cellulose efanayo ineempembelelo zokulibaziseka ezahlukeneyo kwiimveliso ezahlukeneyo ze-hydration, ebonisa ukuba iimveliso ze-samente ze-Portland zineempembelelo ezahlukeneyo kwifiber. I-adsorption ye-cellulose ether iyakhetha, kwaye i-adsorption ye-cellulose ether kwimveliso ye-cement hydration nayo iyakhetha.
Ixesha lokuposa: Feb-27-2023