Phello ea cellulose ether mochesong oa hydration ea samente e fapaneng le ore e le 'ngoe

liphello tsa cellulose ether mocheso oa hydration oa samente ea Portland, samente ea sulfoaluminate, tricalcium silicate le tricalcium aluminate ka 72h li ne li bapisoa le tlhahlobo ea isothermal calorimetry. Liphello li bontša hore cellulose ether e ka fokotsa haholo tekanyo ea hydration le mocheso oa ho lokolloa ha Portland samente le silicate ea tricalcium, 'me phello ea ho fokotseha ha sekhahla sa hydration le mocheso oa ho lokolloa ha tricalcium silicate ke ea bohlokoa haholo. Phello ea cellulose ether ho fokotsa sekhahla sa ho lokolloa ha mocheso oa hydration ea samente ea sulfoaluminate e fokola haholo, empa e na le phello e fokolang ho ntlafatsa sekhahla sa ho lokolloa ha mocheso oa hydration ea tricalcium aluminate. Cellulose ether e tla khabisoa ke lihlahisoa tse ling tsa hydration, kahoo e liehe ho hlahisa lihlahisoa tsa hydration, ebe e ama sekhahla sa ho lokolloa ha mocheso oa samente le ore e le 'ngoe.

Mantsoe a bohlokoa:cellulose ether; Samente; Ore e le 'ngoe; Mocheso oa hydration; adsorption

1. Selelekela

Cellulose ether ke ntho ea bohlokoa ea ho tenya le ntho e bolokang metsi seretseng se omeletseng se tsoakiloeng, konkreite e itšebetsang le lisebelisoa tse ling tse ncha tse thehiloeng ho samente. Leha ho le joalo, cellulose ether e tla liehisa samente hydration, e leng ho loketseng ho ntlafatsa nako ea ts'ebetso ea thepa e thehiloeng ho samente, ho ntlafatsa ho tsitsa ha seretse le tahlehelo ea nako ea konkreite, empa hape e ka liehisa tsoelo-pele ea kaho. Haholo-holo, e tla ba le liphello tse mpe holim'a seretse le konkreite e sebelisoang maemong a tlase a mocheso. Ka hona, ho bohlokoa haholo ho utloisisa molao oa cellulose ether mabapi le kinetics ea samente ea hydration.

OU le Pourchez ba ile ba ithuta ka mokhoa o hlophisitsoeng liphello tsa likarolo tsa limolek'hule tse kang boima ba molek'hule ea cellulose ether, mofuta oa substituent kapa tekanyo ea substitution ho samente hydration kinetics, 'me ba fihletse liqeto tse ngata tsa bohlokoa: Bokhoni ba hydroxyethyl cellulose ether (HEC) ho lieha ho phalla ha metsi. samente hangata e matla ho feta ea methyl cellulose ether (HPMC), hydroxymethyl ethyl cellulose ether (HEMC) le methyl cellulose ether (MC). Ka selulose ether e nang le methyl, e ka tlaase ho methyl content, matla a matla a ho lieha ho phalla ha samente; Ha boima ba limolek'hule ba cellulose ether bo le tlase, matla a ho lieha ho phalla ha samente a matlafala. Liqeto tsena li fana ka motheo oa saense oa ho khetha cellulose ether ka nepo.

Bakeng sa likarolo tse fapaneng tsa samente, phello ea cellulose ether ho samente hydration kinetics le eona ke bothata bo amehang haholo lits'ebetsong tsa boenjiniere. Leha ho le joalo, ha ho na lipatlisiso mabapi le ntlha ena. Pampiring ena, tšusumetso ea cellulose ether ho hydration kinetics ea samente e tloaelehileng ea Portland, C3S(tricalcium silicate), C3A(tricalcium aluminate) le samente ea sulfoaluminate (SAC) e ile ea ithutoa ka tlhahlobo ea isothermal calorimetry, e le ho utloisisa tšebelisano le ho feta. mochine o ka hare pakeng tsa cellulose ether le lihlahisoa tsa samente tsa hydration. E fana ka motheo o mong oa saense bakeng sa tšebeliso e utloahalang ea cellulose ether linthong tse thehiloeng ho samente hape e fana ka motheo oa lipatlisiso bakeng sa tšebelisano pakeng tsa metsoako e meng le lihlahisoa tsa samente tsa hydration.

2. Teko

2.1 Lisebelisoa tse tala

(1) samente e tloaelehileng ea Portland (P · 0). E entsoe ke Wuhan Huaxin Cement Co., LTD., litlhaloso ke P · 042.5 (GB 175-2007), e khethiloeng ke maqhubu a mefuta-futa ea mofuta oa X-ray fluorescence spectrometer (AXIOS e tsoetseng pele, PANalytical Co., LTD.). Ho latela tlhahlobo ea software ea JADE 5.0, ntle le liminerale tsa samente tsa C3S, C2s, C3A, C4AF le gypsum, lisebelisoa tse tala tsa samente li kenyelletsa calcium carbonate.

(2) samente ea sulfoaluminate (SAC). Samente e thata e potlakileng ea sulfoaluminate e hlahisoang ke Zhengzhou Wang Lou Cement Industry Co., Ltd. ke R.Star 42.5 (GB 20472-2006). Lihlopha tsa eona tse kholo ke calcium sulfoaluminate le dicalcium silicate.

(3) tricalcium silicate (C3S). Tobetsa Ca(OH) 2, SiO2, Co2O3 le H2O ka 3: 1: 0.08: Karo-karolelano ea boima ba 10 e ne e tsoakane ka ho lekana 'me e hatelloa tlas'a khatello e sa khaotseng ea 60MPa ho etsa cylindrical green billet. Billet e ne e calcined ka 1400 ℃ bakeng sa 1.5 ~ 2 h ka lere la silicon-molybdenum sebōpi sa mocheso o phahameng oa mocheso oa motlakase, 'me e kenngoa ka ontong ea microwave bakeng sa ho futhumatsa microwave e eketsehileng bakeng sa 40min. Ka mor'a ho ntša billet, e ile ea pholile ka tšohanyetso 'me ea robeha khafetsa le ho calcined ho fihlela litaba tsa CaO ea mahala sehlahisoa se felileng se le ka tlase ho 1.0%

(4) tricalcium aluminate (c3A). CaO le A12O3 li ne li tsoakoa ka ho lekana, li calcined ka 1450 ℃ bakeng sa 4 h ka sebōping sa motlakase sa silicon-molybdenum, ho siloa hore e be phofo, 'me ka makhetlo-khetlo ho fihlela litaba tsa CaO ea mahala li le ka tlase ho 1.0%,' me litlhōrō tsa C12A7 le CA li ne li le teng. hlokomolohile.

(5) cellulose ether. Mosebetsi o fetileng o ile oa bapisa liphello tsa mefuta ea 16 ea li-cellulose ethers ka tekanyo ea hydration le mocheso oa tokollo ea samente e tloaelehileng ea Portland, 'me o fumane hore mefuta e sa tšoaneng ea li-cellulose ethers e na le phapang e kholo holim'a molao oa hydration le mocheso oa samente,' me o hlahlobile mochine o ka hare. ea phapang ena ea bohlokoa. Ho ea ka liphetho tsa phuputso e fetileng, ho ile ha khethoa mefuta e meraro ea cellulose ether e nang le phello e hlakileng ea ho fokotsa samente e tloaelehileng ea Portland. Tsena li kenyelletsa hydroxyethyl cellulose ether (HEC), hydroxypropyl methyl cellulose ether (HPMC), le hydroxyethyl methyl cellulose ether (HEMC). The viscosity ea cellulose ether e ne e lekantsoe ka viscometer ea rotary e nang le tlhahlobo ea tlhahlobo ea 2%, mocheso oa 20 ℃ le lebelo la ho potoloha la 12 r / min. The viscosity ea cellulose ether e ne e lekantsoe ka viscometer ea rotary e nang le tlhahlobo ea tlhahlobo ea 2%, mocheso oa 20 ℃ le lebelo la ho potoloha la 12 r / min. Tekanyo ea molar substitution ea cellulose ether e fanoa ke moetsi.

(6) Metsi. Sebelisa metsi a se nang distilled.

2.2 Mokhoa oa teko

Mocheso oa hydration. TAM Air 8-channel isothermal calorimeter e hlahisoang ke TA Instrument Company e ile ea amoheloa. Lisebelisoa tsohle tse tala li ne li bolokoa mocheso o sa fetoheng ho leka mocheso (joalo ka (20± 0.5) ℃) pele ho teko. Ntlha ea pele, 3 g samente le 18 mg cellulose ether phofo li ile tsa kenngoa ka calorimeter (karolelano ea boima ba cellulose ether ho thepa ea cemellative e ne e le 0.6%). Ka mor'a ho kopanya ka ho feletseng, metsi a tsoakiloeng (metsi a bobeli a silafalitsoeng) a ile a kenngoa ho ea ka tekanyo e boletsoeng ea samente ea metsi 'me a tsosoa ka ho lekana. Ka mor'a moo, e ile ea kenngoa ka potlako ho calorimeter bakeng sa tlhahlobo. Karolelano ea setlamo sa metsi ea c3A ke 1.1, 'me karolelano ea se tlamang metsi ea lisebelisoa tse ling tse tharo tsa samente ke 0.45.

3. Liphetho le lipuisano

3.1 Liphetho tsa liteko

Litlamorao tsa HEC, HPMC le HEMC mabapi le sekhahla sa ho lokolloa ha mocheso oa hydration le sekhahla sa ho lokolloa ha mocheso oa samente e tloaelehileng ea Portland, C3S le C3A nakong ea lihora tse 72, le litlamorao tsa HEC ho sekhahla sa ho lokolloa ha mocheso oa hydration le sekhahla sa ho lokolloa ha mocheso oa samente ea sulfoaluminate. ka hare ho 72 h, HEC ke cellulose ether e nang le phello e matla ka ho fetisisa ea ho lieha ho phalla ha samente e 'ngoe le ore e le' ngoe. Ho kopanya litlamorao tse peli, ho ka fumanoa hore ka phetoho ea sebopeho sa lisebelisoa tsa cementitious, cellulose ether e na le litlamorao tse fapaneng mabapi le sekhahla sa tokollo ea mocheso oa hydration le tokollo ea mocheso o akaretsang. The kgethilweng selulose ether ka haholo fokotsa hydration le mocheso tokollo lebelo la tloaelehileng Portland samente le C, S, haholo-holo lelefatsa nako induction nako, lieha ponahalo ea hydration le mocheso tokollo tlhōrō, har'a tseo selulose ether ho C, S hydration le ho lieha ho lokolloa ha mocheso ho hlakile ho feta hydration e tloaelehileng ea samente ea Portland le ho lieha ho lokolloa ha mocheso; Cellulose ether e ka boela ea liehisa sekhahla sa ho lokolloa ha mocheso oa sulfoaluminate samente hydration, empa bokhoni ba ho lieha bo fokola haholo, 'me haholo-holo bo lieha ho phalla ka mor'a lihora tse 2; Bakeng sa sekhahla sa ho lokolloa ha mocheso oa C3A hydration, cellulose ether e na le bokhoni bo fokolang ba ho potlakisa.

3.2 Tlhahlobo le puisano

Mochine oa cellulosic ether o liehisa samente hydration. Silva le al. ho nahanoa hore cellulosic ether e ekelitse viscosity ea tharollo ea pore mme e sitisa sekhahla sa ho sisinyeha ha ionic, ka hona ho liehisa samente hydration. Leha ho le joalo, lingoliloeng tse ngata li belaella khopolo ena, kaha liteko tsa bona li fumane hore li-cellulose ethers tse nang le viscosity e tlaase li na le matla a matla a ho lieha ho phalla ha samente. Ha e le hantle, nako ea ho tsamaea ha ion kapa ho falla e khutšoanyane hoo ho totobetseng hore ha e bapisoe le nako ea ho lieha ha hydration ea samente. Phatlalatso pakeng tsa cellulose ether le lihlahisoa tsa samente tsa hydration e nkoa e le lebaka la sebele la ho lieha ha samente hydration ka cellulose ether. Cellulose ether e khabisoa habonolo holim'a lihlahisoa tsa hydroxide tse kang calcium hydroxide, CSH gel le calcium aluminate hydrate, empa ha ho bonolo ho adsorbed ka karolo ea ettringite le unhydrated, 'me matla a adsorption ea cellulose ether ka calcium hydroxide e phahame ho feta. ea gel ea CSH. Ka hona, bakeng sa lihlahisoa tse tloaelehileng tsa Portland samente hydration, cellulose ether e na le tieho e matla ka ho fetisisa ho calcium hydroxide, tieho e matla ka ho fetisisa ea calcium, tieho ea bobeli ho CSH gel, le tieho e fokolang ka ho fetisisa ho ettringite.

Liphuputso tse fetileng li bontšitse hore adsorption pakeng tsa polysaccharide e seng ionic le karolo ea liminerale haholo-holo e kenyelletsa hydrogen bonding le lik'hemik'hale tse rarahaneng, 'me liphello tsena tse peli li etsahala pakeng tsa sehlopha sa hydroxyl sa polysaccharide le tšepe ea hydroxide holim'a liminerale. Liu et al. Ho feta moo, adsorption e lipakeng tsa polysaccharides le metal hydroxides ke tšebelisano ea acid-base, 'me polysaccharides e le li-acids le metal hydroxides e le metheo. Bakeng sa polysaccharide e fanoeng, alkalinity ea bokaholimo ba liminerale e lekanya matla a tšebelisano lipakeng tsa polysaccharides le liminerale. Har'a likarolo tse 'nè tsa gelling tse ithutoang pampiring ena, likarolo tse ka sehloohong tsa tšepe kapa tse seng tsa tšepe li kenyelletsa Ca, Al le Si. Ho ea ka tatellano ea ts'ebetso ea tšepe, alkalinity ea hydroxides ea bona ke Ca(OH)2>Al(OH3>Si(OH)4. Ha e le hantle, tharollo ea Si(OH)4 e na le asiti' me ha e adsorb cellulose ether. litaba tsa Ca(OH)2 holim'a lihlahisoa tsa samente tsa hydration li etsa qeto ea matla a adsorption ea lihlahisoa tsa hydration le cellulose ether Hobane calcium hydroxide, CSH gel (3CaO · 2SiO2 · 3H20), ettringite (3CaO · Al2O3 · 3CaSO4 · 32H2O) le calcium aluminate hydrate (3CaO · Al2O3 · 6H2O) ka dikahare tsa inorganic oxides ea CaO ke 100%, 58.33%, 49.56% le 62 .2%. aluminate> CSH gel> ettringite, e lumellanang le liphello tsa lingoliloeng.

Lihlahisoa tsa hydration tsa c3S haholo-holo li kenyelletsa Ca(OH) le gel ea csH, le cellulose ether e na le phello e ntle ea ho lieha ho tsona. Ka hona, cellulose ether e na le tieho e hlakileng haholo ho C3s hydration. Ntle le c3S, samente e tloaelehileng ea Portland e boetse e kenyelletsa C2s hydration e liehang, e etsang hore phello ea ho lieha ha cellulose ether e se ke ea bonahala qalong. Lihlahisoa tsa hydration tsa silicate tse tloaelehileng li boetse li kenyelletsa ettringite, 'me phello ea ho lieha ha cellulose ether e futsanehile. Ka hona, bokhoni ba ho lieha ha cellulose ether ho c3s bo matla ho feta ba samente e tloaelehileng ea Portland e hlokometsoeng tekong.

C3A e tla qhibiliha le ho nosetsa kapele ha e kopana le metsi, 'me lihlahisoa tsa hydration hangata ke C2AH8 le c4AH13,' me mocheso oa hydration o tla lokolloa. Ha tharollo ea C2AH8 le c4AH13 e fihla ho tlala, crystallization ea C2AH8 le C4AH13 hexagonal sheet hydrate e tla thehoa, 'me lebelo la ho arabela le mocheso oa hydration li tla fokotseha ka nako e le' ngoe. Ka lebaka la ho ata ha cellulose ether ka holim'a calcium aluminate hydrate (CxAHy), boteng ba cellulose ether bo ka liehisa ho khanya ha C2AH8 le C4AH13 hexagonal-plate hydrate, ho baka ho fokotseha ha sekhahla sa karabelo le sekhahla sa ho lokolloa ha mocheso ho feta moo. ea C3A e hloekileng, e bontšang hore cellulose ether e na le matla a fokolang a ho potlakisa ho C3A hydration. Ke habohlokoa ho hlokomela hore tekong ena, cellulose ether e na le matla a fokolang a ho potlakisa ho hydration ea c3A e hloekileng. Leha ho le joalo, ka samente e tloaelehileng ea Portland, hobane c3A e tla itšoara ka gypsum ho theha ettringite, ka lebaka la tšusumetso ea ca2 + ho leka-lekana ka tharollo ea slurry, cellulose ether e tla lieha ho thehoa ha ettringite, kahoo e lieha ho phalla ha c3A.

Ho tsoa litlamorao tsa HEC, HPMC le HEMC mabapi le hydration le sekhahla sa ho lokolloa ha mocheso le ho lokolloa ha mocheso oa samente e tloaelehileng ea Portland, C3S le C3A nakong ea lihora tse 72, le litlamorao tsa HEC mabapi le hydration le sekhahla sa ho lokolloa ha mocheso le ho lokolloa ha mocheso oa sulfoaluminate. samente ka hare ho 72 h, ho ka bonoa hore har'a li-ether tse tharo tsa cellulose tse khethiloeng, Bokhoni ba ho lieha ho phalla ha c3s le samente ea Portland e ne e le matla ka ho fetisisa ho HEC, e lateloa ke HEMC, le e fokolang ka ho fetisisa ho HPMC. Mabapi le C3A, bokhoni ba li-cellulose ethers tse tharo tsa ho potlakisa hydration le tsona li le ka tatellano e tšoanang, ke hore, HEC ke eona e matla ka ho fetisisa, HEMC ke ea bobeli, HPMC ke e fokolang le e matla ka ho fetisisa. Sena se ile sa tiisa ka bobeli hore cellulose ether e liehile ho thehoa ha lihlahisoa tsa hydration tsa thepa ea gelling.

Lihlahisoa tse ka sehloohong tsa hydration tsa samente ea sulfoaluminate ke ettringite le Al(OH) 3 gel. C2S ka samenteng ea sulfoaluminate le eona e tla hydrate ka thoko ho etsa Ca(OH)2 le cSH gel. Hobane adsorption ea cellulose ether le ettringite e ka hlokomolohuoa, 'me hydration ea sulfoaluminate e potlakile haholo, ka hona, sethaleng sa pele sa hydration, cellulose ether ha e na phello e fokolang ho tekanyo ea ho lokolloa ha mocheso oa hydration ea samente ea sulfoaluminate. Empa ho fihlela nako e itseng ea hydration, hobane c2s tla ka thoko hydrate ho hlahisa Ca(OH)2 le CSH gel, lihlahisoa tsena tse peli hydration tla lieha ka cellulose ether. Ka hona, ho ile ha hlokomeloa hore cellulose ether e liehile ho phalla ha samente ea sulfoaluminate ka mor'a lihora tse peli.

4. Qetello

Ka pampiri ena, ka tlhahlobo ea isothermal calorimetry, molao oa tšusumetso le mokhoa oa ho thehoa ha cellulose ether ka mocheso oa hydration oa samente e tloaelehileng ea Portland, c3s, c3A, samente ea sulfoaluminate le likarolo tse ling tse fapaneng le ore e le 'ngoe ka 72 h li ne li bapisoa. Liqeto tse kholo ke tse latelang:

(1) Cellulose ether e ka fokotsa haholo lebelo la ho lokolloa ha mocheso oa hydration oa samente e tloaelehileng ea Portland le silicate ea tricalcium, 'me phello ea ho fokotsa sekhahla sa ho lokolloa ha mocheso oa tricalcium silicate ke ea bohlokoa haholo; Phello ea cellulose ether ho fokotsa sekhahla sa ho lokolloa ha mocheso oa samente ea sulfoaluminate e fokola haholo, empa e na le phello e fokolang ho ntlafatsa sekhahla sa ho lokolloa ha mocheso oa tricalcium aluminate.

(2) cellulose ether e tla khabisoa ke lihlahisoa tse ling tsa hydration, kahoo li liehe ho hlahisa lihlahisoa tsa hydration, tse amang mocheso oa mocheso oa samente hydration. Mofuta le bongata ba lihlahisoa tsa hydration li fapane bakeng sa likarolo tse fapaneng tsa tšepe ea samente, kahoo phello ea cellulose ether mocheso oa bona oa hydration ha e tšoane.