Ama-cellulose ethers, ikakhulukazi i-hydroxypropylmethylcellulose (HPMC) kanye ne-methylhydroxyethylcellulose (MHEC), asetshenziswe kabanzi njengezithasiselo ze-cementitious material ekufakweni kwezicelo zokwakha.Ezaziwa ngezinto ezigcina amanzi, lezi zinto zingathuthukisa ukusebenza, i-rheology namandla esibopho sezinto zikasimende.Kodwa-ke, ithonya labo ku-cement hydration alicaci ngaso sonke isikhathi.
I-Cement hydration ibhekisela ekuphenduleni kwamakhemikhali phakathi kwamanzi nezinto zikasimende ukukhiqiza imikhiqizo ye-hydration efana ne-calcium silicate hydrate (CSH) ne-calcium hydroxide (Ca(OH)2).Le nqubo ibalulekile ekuthuthukisweni kwamandla kakhonkolo nokuqina.
Ukwengezwa kwama-cellulose ether ezintweni zikasimende kungaba nemiphumela emihle nemibi enqubweni ye-hydration.Ngakolunye uhlangothi, ukusebenza kokugcinwa kwamanzi kwe-cellulose ether kungakhuthaza usimende ukuthi uqhubeke nokuthola amanzi okusabela, ngaleyo ndlela kwandise isivinini kanye nezinga lokugeleza kwamanzi.Lokhu kunciphisa isikhathi sokusetha, kusheshisa ukuthuthukiswa kwamandla futhi kuthuthukise izakhiwo eziphelele zekhonkrithi.
I-Cellulose ether ingasebenza njenge-colloid evikelayo ukuvimbela ukuhlanganisa kanye nokuxazululwa kwezinhlayiya zikasimende.Lokhu kubangela i-microstructure efanayo futhi ezinzile, eqhubeka ithuthukisa izakhiwo zemishini neziqinile zikakhonkolo.
Ngakolunye uhlangothi, ukusetshenziswa ngokweqile kwama-cellulose ethers kungaba nomthelela omubi ukugeleza kukasimende.Ngenxa yokuthi i-cellulose ether ine-hydrophobic ngokwengxenye, ivimbela ukungena kwamanzi ku-gelling material, okuholela ekubambezelekeni noma ekungapheleleni kwe-hydration.Lokhu kubangela ukuncipha kwamandla nokuqina kukakhonkolo.
Uma ukugxila kwe-cellulose ether kuphezulu kakhulu, kuzothatha isikhala ku-slurry kasimende okufanele igcwaliswe izinhlayiya zikasimende.Ngenxa yalokho, inani eliphelele lezinto eziqinile ze-slurry lizokwehla, okuholela ekunciphiseni kwezakhiwo zemishini.Ama-ether e-cellulose engeziwe angasebenza futhi njengesithiyo, avimbele ukusebenzisana phakathi kwezinhlayiya zikasimende namanzi, kuqhubeke kubambezela inqubo yokukhipha amanzi.
Kubalulekile ukunquma inani eliphelele le-cellulose ether ezosetshenziswa ukuthuthukisa izici ze-gelled material ngenkathi ugwema noma yimuphi umthelela ongemuhle ku-hydration.Inani lincike ezintweni eziningi, njengohlobo lwe-cellulose ether, ukwakheka kukasimende, isilinganiso sikasimende wamanzi nezimo zokuphulukisa.
Ama-cellulose ethers, ikakhulukazi i-HPMC ne-MHEC, angaba nomthelela omuhle ku-hydration kasimende, kuye ngokugxila kwawo kanye nokwakheka okuqondile kwezinto zikasimende.Inani le-cellulose ether elisetshenzisiwe kufanele licatshangelwe ngokucophelela ukuze kuzuzwe izakhiwo ezifunwayo ngaphandle kokuphazamisa izakhiwo zekhonkrithi.Ngokusetshenziswa okufanele kanye nokwenza kahle, ama-cellulose ether angaba nomthelela ekuthuthukisweni kwezinto zokwakha ezihlala isikhathi eside, ezihlala isikhathi eside futhi ezisimeme.
Isikhathi sokuthumela: Aug-23-2023