Yiyiphi impembelelo enayo i-cellulose ether kwizinto ezisekwe kwisamente?

1. Ubushushu be-hydration

Ngokwe-curve yokukhululwa kobushushu be-hydration ngokuhamba kwexesha, inkqubo ye-hydration ye-samente idla ngokuhlukana ibe ngamanqanaba amahlanu, oko kukuthi, ixesha lokuqala lokuhamba (0 ~ 15min), ixesha lokungeniswa (15min ~ 4h), ixesha lokukhawuleza kunye nokumisela (4h ~ 8h), ukuhla kunye nokuqina kwexesha (8h ~ 24h), kunye ne-curing 24h (1 ~ 24h)

Iziphumo zovavanyo zibonisa ukuba kwisigaba sokuqala sokungeniswa (oko kukuthi, ixesha lokuqala le-hydration), xa inani le-HEMC liyi-0.1% xa kuthelekiswa ne-cement slurry engenanto, i-peak exothermic ye-slurry iqhubekile kwaye i-peak inyuke kakhulu. Xa isixa seHEMCukwanda ukuya Xa kungaphezulu kwe-0.3%, i-peak yokuqala ye-exothermic ye-slurry ilibazisekile, kwaye ixabiso eliphakamileyo liyancipha ngokuthe ngcembe ngokunyuka komxholo we-HEMC; I-HEMC ngokuqinisekileyo iya kulibazisa ixesha lokungeniswa kunye nexesha lokukhawuleza kwe-cement slurry, kwaye umxholo omkhulu , ixesha elide lokungeniswa, umva emva kwexesha lokukhawuleza, kunye nencinci i-exothermic peak; Ukuguqulwa komxholo we-cellulose ether ayinayo impembelelo ecacileyo kubude bexesha lokunciphisa kunye nexesha lokuzinza kwe-slurry ye-samente, njengoko kubonisiwe kwi-Figure 3 (a) Kuboniswa ukuba i-cellulose ether inokunciphisa ubushushu be-hydration ye-cement paste kwiiyure ze-72, kodwa xa ubushushu be-hydration bude kuneeyure ze-36 ze-ether ze-ether ze-ether ze-ether ze-ether ze-heat content zinefuthe elincinci le-cellulose. coma, njengomfanekiso 3(b).

Umzobo we-3 Ukwahluka kwendlela yokukhutshwa kobushushu be-hydration kwintlama yesamente enomxholo owahlukileyo we-cellulose ether (HEMC)

2. Miimpawu ze-echanical:

Ngokufunda iindidi ezimbini ze-cellulose ethers kunye ne-viscosities ye-60000Pa · kunye ne-100000Pa · s, kwafunyaniswa ukuba amandla oxinzelelo lodaka olulungisiweyo oluxutywe ne-methyl cellulose ether yehla ngokuthe ngcembe ngokunyuka komxholo wayo. Amandla oxinzelelo lodaka olulungisiweyo oluxutywe ne-100000Pa · i-viscosity hydroxypropyl methyl cellulose ether inyuka kuqala kwaye iyancipha ngokunyuka komxholo wayo (njengoko kubonisiwe kuMfanekiso 4). Kubonisa ukuba ukufakwa kwe-methyl cellulose ether kuya kunciphisa kakhulu amandla oxinzelelo lwe-cement mortar. Okukhona ubuninzi bemali, amandla amancinci aya kuba; i-viscosity encinci, impembelelo enkulu ekulahlekeni kwamandla oxinzelelo lodaka; I-hydroxypropyl methyl cellulose ether Xa i-dosage ingaphantsi kwe-0.1%, amandla okucinezela udaka anokongezwa ngokufanelekileyo. Xa i-dosage ingaphezulu kwe-0.1%, amandla oxinzelelo omdaka uya kuncipha ngokunyuka kwe-dosage, ngoko ke umthamo kufuneka ulawulwe kwi-0.1%.

I-Fig.4 3d, 7d kunye ne-28d amandla oxinzelelo lwe-MC1, MC2 kunye ne-MC3 udaka lwesamente olulungisiweyo

(i-Methyl cellulose ether, i-viscosity 60000Pa·S, emva koko ekubhekiselwa kuyo njenge-MC1; i-methyl cellulose ether, i-viscosity 100000Pa·S, ekubhekiselwa kuyo njenge-MC2; i-hydroxypropyl methylcellulose ether, i-viscosity 100000Pa · S, ekubhekiselwa kuyo njenge-MC2).

3. Cixesha lokuphumla:

Ngokulinganisa ixesha lokumisela i-hydroxypropyl methylcellulose ether kunye ne-viscosity ye-100000Pa · kwiidosi ezahlukeneyo ze-samente ye-samente, kwafunyaniswa ukuba ngokunyuka kwe-HPMC ye-dosage, ixesha lokuqala lokumisela kunye nexesha lokugqibela lokumisela i-sement mortar yandiswe ixesha elide. Xa ugxininiso luyi-1%, ixesha lokuqala lokumisela lifikelela kwimizuzu ye-510, kwaye ixesha lokugqibela lokumisela lifikelela kwimizuzu ye-850. Xa kuthelekiswa nesampuli engenanto, ixesha lokuqala lokumisela landiswa ngemizuzu ye-210, kwaye ixesha lokugqibela lokumisela landiswa ngemizuzu ye-470 (njengoko kuboniswe kuMfanekiso 5). Ingaba i-HPMC ene-viscosity ye-50000Pa s, i-100000Pa s okanye i-200000Pa s, inokulibazisa ukusetyenzwa kwesamente, kodwa xa kuthelekiswa ne-ethers ezintathu ze-cellulose, ixesha lokuqala lokumisela kunye nexesha lokugqibela lokumisela lide kunye nokunyuka kwe-viscosity, njengoko kubonisiwe kwi-Figure 6. Oku kungenxa yokuba i-cellulose ether i-adsorbed kumphezulu wamasuntswana e-samente, ethintela amanzi ukuba angadibanisi namasuntswana e-samente, ngaloo ndlela alibazisa ukuhanjiswa kwesamente. Ubukhulu be-viscosity ye-cellulose ether, i-adsorption layer ingqindilili kumphezulu wamasuntswana e-samente, kwaye ibaluleke ngakumbi isiphumo sokubuyiswa.

Umzobo we-5 Impembelelo yesiqulatho se-ether ye-cellulose ekubekeni ixesha lodaka

Umzobo.6 Impembelelo yee-viscosities ezahlukeneyo ze-HPMC kwixesha lokumisela intlama yesamente

(MC-5(50000Pa·s), MC-10(100000Pa·s) kunye ne-MC-20(200000Pa·s))

I-Methyl cellulose ether kunye ne-hydroxypropyl methyl cellulose ether iya kwandisa kakhulu ixesha lokumisela i-sement slurry, enokuqinisekisa ukuba i-cement slurry inexesha elaneleyo kunye namanzi okusabela kwe-hydration, kunye nokusombulula ingxaki yamandla aphantsi kunye nenqanaba lokugqibela le-samente slurry emva kokuqina. ingxaki yokuqhekeka.

4. Ukugcinwa kwamanzi:

Umphumo womxholo we-cellulose ether ekugcinweni kwamanzi wafundwa. Kufunyenwe ukuba ngokunyuka komxholo we-cellulose ether, izinga lokugcinwa kwamanzi kwi-mortar liyenyuka, kwaye xa umxholo we-cellulose ether umkhulu kune-0.6%, izinga lokugcinwa kwamanzi lihlala lizinzile. Nangona kunjalo, xa kuthelekiswa neentlobo ezintathu ze-cellulose ethers (HPMC kunye ne-viscosity ye-50000Pa s (MC-5), i-100000Pa s (MC-10) kunye ne-200000Pa s (MC-20)), impembelelo ye-viscosity ekugcinweni kwamanzi yahlukile. Ubudlelwane phakathi kwezinga lokugcinwa kwamanzi: MC-5.