Mmetụta nke cellulose ether na okpomọkụ nke hydration nke ciment dị iche iche na otu ore

mmetụta nke cellulose ether na hydration okpomọkụ nke Portland ciment, sulfoaluminate ciment, tricalcium silicate na tricalcium aluminate na 72h tụnyere isothermal calorimetry test. Nsonaazụ gosiri na cellulose ether nwere ike ibelata hydration na okpomọkụ ntọhapụ ọnụego nke Portland ciment na tricalcium silicate, na mbelata mmetụta na hydration na okpomọkụ ntọhapụ ọnụego nke tricalcium silicate dị ịrịba ama karị. Mmetụta nke cellulose ether na ibelata ọnụego ntọhapụ okpomọkụ nke hydration nke ciment sulfoaluminate adịghị ike nke ukwuu, ma ọ na-enwe mmetụta na-adịghị ike n'ịkwalite ọnụego ntọhapụ okpomọkụ nke hydration nke tricalcium aluminate. Cellulose ether ga-adsorbed site ụfọdụ ngwaahịa hydration, si otú na-egbu oge crystallization nke hydration ngwaahịa, na mgbe ahụ na-emetụta hydration okpomọkụ ntọhapụ ọnụego nke ciment na otu ore.

Isi okwu:cellulose ether; Simenti; Otu ore; Okpomọkụ nke hydration; adsorption

1. Okwu mmalite

Cellulose ether bụ ihe dị mkpa na-eme ka mmiri sie ike na ihe na-ejigide mmiri n'ime ngwa ngwa agwakọta akọrọ, kọmpat na-ejikọta onwe ya na ihe ndị ọzọ dabeere na ciment. Otú ọ dị, cellulose ether ga-egbukwa oge ciment hydration, nke dị mma iji melite oge ọrụ nke ihe ndị dabeere na ciment, melite ngwa agha agbanwe agbanwe na ihe slump oge ọnwụ, ma nwekwara ike igbu oge na-ewu ụlọ. Karịsịa, ọ ga-enwe mmetụta ọjọọ na ngwa agha na ihe eji eme ihe na ọnọdụ ọnọdụ okpomọkụ dị ala. Ya mere, ọ dị ezigbo mkpa ịghọta iwu cellulose ether na ciment hydration kinetics.

OU na Pourchez ji nlezianya mụọ mmetụta nke mkpụrụ ndụ mkpụrụ ndụ dị ka ịdị arọ nke cellulose ether, ụdị ihe nnọchi ma ọ bụ ogo nke nnọchi na ciment hydration kinetics, wee wepụta ọtụtụ nkwubi okwu dị mkpa: Ikike nke hydroxyethyl cellulose ether (HEC) na-egbu oge hydration nke ciment na-esikarị ike karịa nke methyl cellulose ether (HPMC), hydroxymethyl ethyl cellulose ether (HEMC) na methyl cellulose ether (MC). N'ime cellulose ether nke nwere methyl, na-ebelata ọdịnaya methyl, ike na-adịwanye ike igbu oge hydration nke ciment; N'ịdị arọ molekụla nke cellulose ether dị ala, ka ike na-adịwanye ike igbu oge hydration nke ciment. Nkwubi okwu ndị a na-enye ntọala sayensị maka ịhọrọ cellulose ether nke ọma.

Maka akụkụ dị iche iche nke ciment, mmetụta nke cellulose ether na ciment hydration kinetics bụkwa nsogbu dị oke mkpa na ngwa injinia. Agbanyeghị, ọ nweghị nyocha n'akụkụ a. N'akwụkwọ a, a na-amụ mmetụta nke cellulose ether na hydration kinetics nke nkịtị Portland ciment, C3S (tricalcium silicate), C3A (tricalcium aluminate) na sulfoaluminate ciment (SAC) site na isothermal calorimetry ule, ka a ghọtakwuo mmekọrịta na. usoro ime n'etiti cellulose ether na ciment hydration ngwaahịa. Ọ na-enye ndabere sayensị ọzọ maka iji cellulose ether eme ihe na ihe ndị sitere na ciment ma na-enyekwa ntọala nyocha maka mmekọrịta dị n'etiti ihe mgbakwunye ndị ọzọ na ngwaahịa hydration ciment.

2. Nwale

2.1 Akụrụngwa

(1) simenti Portland nkịtị (P·0). Mepụtara site na Wuhan Huaxin Cement Co., LTD., nkọwapụta bụ P · 042.5 (GB 175-2007), kpebisiri ike site wavelength dispersion ụdị X-ray fluorescence spectrometer (AXIOS Advanced, PANalytical Co., LTD.). Dị ka nyocha nke JADE 5.0 software, na mgbakwunye na ciment clinker mineral C3S, C2s, C3A, C4AF na gypsum, simenti akụrụngwa na-agụnye calcium carbonate.

(2) simenti sulfoaluminate (SAC). Simenti sulfoaluminate siri ike ngwa ngwa nke Zhengzhou Wang Lou Cement Industry Co., Ltd mepụtara bụ R.Star 42.5 (GB 20472-2006). Ndị isi ya bụ calcium sulfoaluminate na dicalcium silicate.

(3) tricalcium silicate (C3S). Pịa Ca (OH) 2, SiO2, Co2O3 na H2O na 3: 1: 0.08: A na-ejikọta ọnụ ọgụgụ nke 10 n'otu n'otu ma tinye ya n'okpuru nrụgide mgbe nile nke 60MPa iji mee cylindrical green billet. A na-edozi billet ahụ na 1400 ℃ maka 1.5 ~ 2 h n'ime mkpanaka silicon-molybdenum dị elu nke ọkụ eletrik, wee kwaga n'ime oven microwave maka ọkụ ọkụ ọzọ maka 40min. Mgbe o wepụsịrị billet ahụ, a jụrụ ya na mberede ma gbajie ya ugboro ugboro wee gbajie ya ruo mgbe ọdịnaya CaO n'efu na ngwaahịa emechara erughị 1.0%

(4) tricalcium aluminate (c3A). A na-agwakọta CaO na A12O3 n'otu n'otu, gbakọọ na 1450 ℃ maka 4 h n'ime ọkụ ọkụ silicon-molybdenum mkpanaka, gbanye ya n'ime ntụ ntụ, ma gbakọọ ugboro ugboro ruo mgbe ọdịnaya nke CaO efu erughi 1.0%, na ọnụ ọgụgụ kasị elu nke C12A7 na CA bụ. leghaara anya.

(5) cellulose ether. Ọrụ gara aga tụnyere mmetụta nke 16 ụdị cellulose ethers na hydration na okpomọkụ ntọhapụ ọnụego nke nkịtị Portland ciment, na chọpụtara na dị iche iche iche iche nke cellulose ethers nwere ịrịba ọdịiche na hydration na okpomọkụ ntọhapụ iwu nke ciment, na nyochaa esịtidem usoro. nke a dị ịrịba ama dị iche. Dị ka nsonaazụ ọmụmụ gara aga si kwuo, a họọrọ ụdị cellulose ether atọ nke nwere mmetụta nkwụghachi azụ na simenti Portland nkịtị. Ndị a gụnyere hydroxyethyl cellulose ether (HEC), hydroxypropyl methyl cellulose ether (HPMC), na hydroxyethyl methyl cellulose ether (HEMC). A tụrụ viscosity nke cellulose ether site na viscometer rotary nwere ntinye ule nke 2%, okpomọkụ nke 20 ℃ yana ọsọ ntụgharị nke 12 r/min. A tụrụ viscosity nke cellulose ether site na viscometer rotary nwere ntinye ule nke 2%, okpomọkụ nke 20 ℃ yana ọsọ ntụgharị nke 12 r/min. Ọ bụ onye nrụpụta nyere ogo ngbanwe molar nke cellulose ether.

(6) Mmiri. Jiri mmiri distilled nke abụọ.

2.2 Usoro ule

Okpomọkụ nke hydration. TAM Air 8-channel isothermal calorimeter nke ụlọ ọrụ TA Instrument mepụtara ka anabatara. A na-edobe akụrụngwa niile na-ekpo ọkụ mgbe niile iji nwalee okpomọkụ (dịka (20± 0.5) ℃) tupu nnwale ahụ. Nke mbụ, 3 g ciment na 18 mg cellulose ether ntụ ntụ na-agbakwunyere n'ime calorimeter (oke nke cellulose ether na ihe cemellative bụ 0.6%). Mgbe agwakọtachara nke ọma, a na-agbakwunye mmiri agwakọta (mmiri distilled nke abụọ) dị ka mmiri simenti akọwapụtara ma kpalie ya nke ọma. Mgbe ahụ, a na-etinye ya ngwa ngwa na calorimeter maka ule. Mmiri na-ekekọta mmiri nke c3A bụ 1.1, na mmiri-njikọ nke ihe atọ ndị ọzọ cementity bụ 0.45.

3. Nsonaazụ na mkparịta ụka

3.1 Nsonaazụ ule

Mmetụta nke HEC, HPMC na HEMC na hydration okpomọkụ ntọhapụ ọnụego na mkpokọta okpomọkụ ntọhapụ ọnụego nke nkịtị Portland ciment, C3S na C3A n'ime 72 h, na mmetụta nke HEC na hydration okpomọkụ ntọhapụ ọnụego na mkpokọta okpomọkụ ntọhapụ ọnụego nke sulfoaluminate ciment. n'ime 72 h, HEC bụ cellulose ether nwere mmetụta igbu oge kachasị ike na hydration nke ciment ndị ọzọ na otu ore. Ijikọta mmetụta abụọ ahụ, enwere ike ịchọta na mgbanwe nke ihe mejupụtara cementious, cellulose ether nwere mmetụta dị iche iche na hydration okpomọkụ ntọhapụ ọnụego na mkpokọta okpomọkụ ntọhapụ. The họrọ cellulose ether nwere ike budata ibelata hydration na okpomọkụ ntọhapụ ọnụego nke nkịtị Portland ciment na C, S, tumadi ogologo oge induction oge, na-egbu oge ọdịdị nke hydration na okpomọkụ tọhapụ elu, n'etiti nke cellulose ether ka C, S hydration na. Okpomọkụ ntọhapụ ọnụego igbu oge pụtara ìhè karịa nkịtị Portland ciment hydration na okpomọkụ ntọhapụ ọnụego igbu oge; Cellulose ether nwekwara ike igbu oge ntọhapụ okpomọkụ nke sulfoaluminate ciment hydration, ma ike igbu oge adịghị ike, ma na-egbu oge hydration mgbe awa 2 gachara; Maka ọnụego ntọhapụ okpomọkụ nke hydration C3A, cellulose ether nwere ike ime ngwa ngwa na-adịghị ike.

3.2 Nyocha na mkparịta ụka

Usoro nke cellulosic ether egbu oge ciment hydration. Silva et al. chere na ether cellulosic mụbara viscosity nke ngwọta pore ma gbochie ọnụ ọgụgụ nke ionic ije, si otú a na-egbu oge ciment hydration. Otú ọ dị, ọtụtụ akwụkwọ enweela obi abụọ n'echiche a, n'ihi na nyocha ha achọpụtala na ethers cellulose na viscosity dị ala nwere ikike dị ike iji gbuo oge mmiri ciment. N'ezie, oge nke ion ije ma ọ bụ ịkwaga dị mkpụmkpụ nke na o doro anya na ọ dịghị atụnyere oge nkwụsị nke ciment hydration. A na-ewere mgbasa ozi dị n'etiti cellulose ether na cement hydration ngwaahịa dị ka ezigbo ihe kpatara igbu oge nke cement hydration site cellulose ether. Cellulose ether na-adị mfe adsorbed n'elu nke hydration ngwaahịa dị ka calcium hydroxide, CSH gel na calcium aluminate hydrate, ma ọ dịghị mfe adsorbed site ettringite na unhydrated oge, na adsorption ikike nke cellulose ether na calcium hydroxide dị elu karịa. nke CSH gel. Ya mere, maka ngwaahịa hydration ciment Portland nkịtị, cellulose ether nwere oge kachasị ike na calcium hydroxide, oge kachasị ike na calcium, nkwụsị nke abụọ na CSH gel, na nkwụsị nke na-adịghị ike na ettringite.

Nnyocha ndị gara aga egosila na mgbasa ozi n'etiti polysaccharide na-abụghị ionic na mineral na-agụnye njikọ hydrogen na mgbagwoju anya, na mmetụta abụọ a na-eme n'etiti ìgwè hydroxyl nke polysaccharide na metal hydroxide n'elu ịnweta. Liu et al. N'ihu nkewa adsorption n'etiti polysaccharides na metal hydroxides dị ka acid-base mmekọrịta, na polysaccharides dị ka acids na metal hydroxides dị ka ntọala. Maka polysaccharide nyere, alkalinity nke ala ịnweta na-ekpebi ike nke mmekọrịta dị n'etiti polysaccharides na mineral. N'ime ihe ndị gelling anọ a mụrụ n'akwụkwọ a, isi ígwè ma ọ bụ ihe ndị na-abụghị metal gụnyere Ca, Al na Si. Dị ka usoro nke ígwè ọrụ si dị, alkalinity nke hydroxides ha bụ Ca (OH) 2> Al (OH3> Si (OH) 4. N'ezie, Si (OH) 4 ngwọta bụ acidic na ọ dịghị adsorb cellulose ether. ọdịnaya nke Ca (OH) 2 n'elu ciment hydration ngwaahịa na-ekpebi ikike adsorption nke ngwaahịa hydration na cellulose ether n'ihi na calcium hydroxide, CSH gel (3CaO · 2SiO2 · 3H20), ettringite (3CaO · Al2O3 · 3CaSO4 · 32H2O). na calcium aluminate hydrate (3CaO · Al2O3 · 6H2O) na ọdịnaya nke inorganic oxides nke CaO bụ 100%, 58.33%, 49.56% na 62 .2% Ya mere, usoro nke ike adsorption ha na cellulose ether bụ calcium hydroxide> calcium aluminate> CSH gel> ettringite, nke kwekọrọ na nsonaazụ na akwụkwọ.

Ngwaahịa hydration nke c3S na-agụnyekarị Ca (OH) na csH gel, na cellulose ether nwere mmetụta igbu oge na ha. Ya mere, cellulose ether nwere oge doro anya na-egbu oge na C3s hydration. E wezụga c3S, simenti Portland nkịtị gụnyekwara C2s hydration nke na-adị nwayọọ, nke na-eme ka mmetụta igbu oge nke cellulose ether pụta ìhè na mmalite. Ngwaahịa hydration nke silicate nkịtị na-agụnye ettringite, na mmetụta igbu oge nke cellulose ether adịghị mma. Ya mere, ike igbu oge nke cellulose ether na c3s siri ike karịa nke simenti Portland nkịtị hụrụ na ule.

C3A ga-agbaze na hydrate ngwa ngwa mgbe ọ na-ezute mmiri, na ngwaahịa hydration na-abụkarị C2AH8 na c4AH13, na okpomọkụ nke hydration ga-ahapụ. Mgbe ngwọta nke C2AH8 na c4AH13 ruru saturation, a ga-emepụta crystallization nke C2AH8 na C4AH13 hexagonal sheet hydrate, na mmeghachi omume mmeghachi omume na okpomọkụ nke hydration ga-ebelata n'otu oge ahụ. N'ihi mgbasa nke cellulose ether na elu calcium aluminate hydrate (CxAHy), ọnụnọ nke cellulose ether ga-egbu oge crystallization nke C2AH8 na C4AH13 hexagonal-plate hydrate, na-akpata mbelata nke mmeghachi omume mmeghachi omume na hydration okpomọkụ ntọhapụ ọnụego karịa nke ahụ. nke C3A dị ọcha, nke na-egosi na cellulose ether nwere ike ngwangwa na-adịghị ike na C3A hydration. Ọ dị mma ịmara na n'ime ule a, cellulose ether nwere ike ime ngwa ngwa na-adịghị ike na hydration nke c3A dị ọcha. Otú ọ dị, na simenti Portland nkịtị, n'ihi na c3A ga-emeghachi omume na gypsum iji mepụta ettringite, n'ihi mmetụta nke ca2+ itule na slurry solution, cellulose ether ga-egbu oge nhazi nke ettringite, si otú ahụ na-egbu oge hydration nke c3A.

Site na mmetụta nke HEC, HPMC na HEMC na hydration na okpomọkụ ntọhapụ ọnụego na mkpokọta okpomọkụ ntọhapụ nke nkịtị Portland ciment, C3S na C3A n'ime 72 h, na mmetụta nke HEC na hydration na okpomọkụ ntọhapụ ọnụego na mkpokọta okpomọkụ ntọhapụ nke sulfoaluminate. ciment n'ime 72 h, a pụrụ ịhụ na n'ime atọ cellulose ethers ahọpụtara, Ikike nke hydration na-egbu oge nke c3s na Portland ciment siri ike na HEC, na-esote HEMC, na adịghị ike na HPMC. N'ihe gbasara C3A, ikike nke cellulose ethers atọ nwere ike ime ngwa ngwa hydration dịkwa n'otu usoro ahụ, ya bụ, HEC bụ ike kachasị ike, HEMC bụ nke abụọ, HPMC bụ onye na-adịghị ike na ike. Nke a kwadoro na cellulose ether egbuola oge ịmepụta ngwaahịa hydration nke ihe gelling.

Isi ngwaahịa hydration nke ciment sulfoaluminate bụ ettringite na Al (OH) 3 gel. C2S na ciment sulfoaluminate ga-agbakwa mmiri iche iche iji mepụta Ca (OH) 2 na cSH gel. N'ihi na adsorption nke cellulose ether na ettringite nwere ike ileghara anya, na hydration nke sulfoaluminate dị ngwa ngwa, ya mere, na mmalite nke hydration, cellulose ether enwechaghị mmetụta na hydration okpomọkụ ntọhapụ ọnụego nke sulfoaluminate ciment. Ma ruo oge ụfọdụ nke hydration, n'ihi na c2s ga-adị iche iche hydrate iji mepụta Ca (OH) 2 na CSH gel, ngwaahịa hydration abụọ a ga-egbu oge site na cellulose ether. Ya mere, a chọpụtara na ether cellulose na-egbu oge hydration nke ciment sulfoaluminate mgbe awa 2 gachara.

4. Nkwubi okwu

N'akwụkwọ a, site na ule calorimetry isothermal, iwu mmetụta na usoro nhazi nke cellulose ether na okpomọkụ hydration nke ciment Portland nkịtị, c3s, c3A, sulfoaluminate ciment na ihe ndị ọzọ dị iche iche na otu ore na 72 h tụnyere. Isi nkwubi okwu bụ ndị a:

(1) Cellulose ether nwere ike budata ibelata hydration okpomọkụ ntọhapụ ọnụego nke nkịtị Portland ciment na tricalcium silicate, na mmetụta nke mbenata hydration okpomọkụ ntọhapụ ọnụego nke tricalcium silicate bụ ihe dị ịrịba ama; Mmetụta nke cellulose ether na ibelata ntọhapụ okpomọkụ nke ciment sulfoaluminate adịghị ike nke ukwuu, ma ọ na-enwe mmetụta na-adịghị ike n'ịkwalite ọnụego ntọhapụ okpomọkụ nke tricalcium aluminate.

(2) cellulose ether ga-adị mma site na ụfọdụ ngwaahịa hydration, si otú ahụ na-egbu oge kristal nke ngwaahịa hydration, na-emetụta ọnụego ntọhapụ okpomọkụ nke ciment hydration. Ụdị na ọnụ ọgụgụ nke ngwaahịa hydration dị iche iche maka akụkụ dị iche iche nke cement bill ore, ya mere mmetụta nke cellulose ether na okpomọkụ hydration ha abụghị otu.