Tshawb nrhiav kev nce qib ntawm cellulose ether hloov mortar

Cov hom cellulose ether thiab nws lub luag haujlwm tseem ceeb hauv kev sib xyaw mortar thiab cov txheej txheem kev soj ntsuam ntawm cov khoom xws li dej tuav, viscosity thiab daim ntawv cog lus muaj zog raug tshuaj xyuas. Lub retarding mechanism thiab microstructure ntawm cellulose ether nyob rau hauv qhuav mix mortar thiab kev sib raug zoo ntawm kev tsim ntawm cov qauv ntawm ib co nyias txheej cellulose ether hloov mortar thiab cov txheej txheem hydration yog expounded. Nyob rau hauv cov ntaub ntawv no, nws yog ib qho tsim nyog yuav tsum tau ceev cov kev tshawb fawb ntawm cov xwm txheej ntawm kev poob dej sai. Cov txheej txheej hydration mechanism ntawm cellulose ether hloov mortar nyob rau hauv lub nyias txheej qauv thiab spatial faib txoj cai ntawm polymer nyob rau hauv lub mortar txheej. Nyob rau hauv lub neej yav tom ntej daim ntawv thov, cov nyhuv ntawm cellulose ether hloov mortar ntawm kub hloov thiab compatibility nrog rau lwm yam additives yuav tsum tau txiav txim siab tag nrho. Txoj kev tshawb no yuav txhawb txoj kev txhim kho ntawm kev siv thev naus laus zis ntawm CE hloov mortar xws li sab nrauv phab ntsa plastering mortar, putty, sib koom mortar thiab lwm cov txheej nyias nyias.

Cov lus tseem ceeb:cellulose ether; Qhuav mix mortar; tshuab

1. Taw qhia

Ordinary qhuav mortar, sab nrauv phab ntsa rwb thaiv tsev mortar, nws tus kheej mortar, waterproof xuab zeb thiab lwm yam mortar qhuav tau dhau los ua ib feem tseem ceeb ntawm lub tsev cov ntaub ntawv raws li nyob rau hauv peb lub teb chaws, thiab cellulose ether yog cov derivatives ntawm natural cellulose ether, thiab tseem ceeb additive additives ntawm ntau yam. ntawm qhuav mortar, retarding, dej tuav, thickening, cua nqus, adhesion thiab lwm yam dej num.

Lub luag haujlwm ntawm CE hauv mortar yog qhov tseem ceeb hauv kev txhim kho kev ua haujlwm ntawm mortar thiab ua kom cov dej ntawm cov cement hauv mortar. Kev txhim kho ntawm mortar workability yog feem ntau xav txog nyob rau hauv dej tuav, los tiv thaiv dai thiab qhib lub sij hawm, tshwj xeeb tshaj yog nyob rau hauv kom ntseeg tau tias nyias txheej mortar carding, plastering mortar kis thiab txhim kho kev tsim kho ceev ntawm tshwj xeeb sib txuas mortar muaj ib qho tseem ceeb kev sib raug zoo thiab nyiaj txiag kev pab cuam.

Txawm hais tias muaj ntau qhov kev tshawb fawb ntawm CE hloov mortar tau ua tiav thiab cov txiaj ntsig tseem ceeb tau ua tiav hauv kev tshawb fawb thev naus laus zis ntawm CE hloov mortar, tseem muaj qhov tsis txaus ntseeg hauv kev tshawb fawb txog kev tshawb fawb ntawm CE hloov mortar, tshwj xeeb tshaj yog kev sib cuam tshuam ntawm CE thiab cement, aggregate thiab matrix nyob rau hauv tshwj xeeb siv ib puag ncig. Yog li, Raws li cov ntsiab lus ntawm cov txiaj ntsig kev tshawb fawb, daim ntawv no qhia tias kev tshawb fawb ntxiv ntawm qhov kub thiab txias thiab sib haum nrog lwm cov khoom siv yuav tsum tau ua.

2,Lub luag haujlwm thiab kev faib tawm ntawm cellulose ether

2.1 Kev faib tawm ntawm cellulose ether

Ntau hom cellulose ether, muaj ze li ib txhiab, feem ntau, raws li kev ua haujlwm ionization tuaj yeem muab faib ua ionic thiab non-ionic hom 2, hauv cov khoom siv cement vim yog ionic cellulose ether (xws li carboxymethyl cellulose, CMC. ) yuav precipitate nrog Ca2+ thiab tsis ruaj khov, yog li tsis tshua siv. Nonionic cellulose ether tuaj yeem ua raws li (1) viscosity ntawm cov txheej txheem aqueous tov; (2) hom kev hloov pauv; (3) kev hloov pauv; (4) lub cev qauv; (5) Kev faib tawm ntawm solubility, thiab lwm yam.

Cov khoom ntawm CE nyob ntawm seb hom, ntau npaum li cas thiab kev faib tawm ntawm cov khoom hloov, yog li CE feem ntau muab faib raws li hom kev hloov pauv. Xws li methyl cellulose ether yog lub ntuj cellulose qabzib chav tsev ntawm hydroxyl yog hloov los ntawm methoxy cov khoom, hydroxypropyl methyl cellulose ether HPMC yog hydroxyl los ntawm methoxy, hydroxypropyl raws li cov khoom hloov. Tam sim no, ntau dua 90% ntawm cov cellulose ethers siv yog methyl hydroxypropyl cellulose ether (MHPC) thiab methyl hydroxyethyl cellulose ether (MHEC).

2.2 Lub luag haujlwm ntawm cellulose ether hauv mortar

Lub luag hauj lwm ntawm CE nyob rau hauv mortar yog feem ntau xav txog nyob rau hauv peb yam nram qab no: zoo heev dej retention muaj peev xwm, cuam tshuam rau qhov sib xws thiab thixotropy ntawm mortar thiab kho rheology.

Kev tuav dej ntawm CE tuaj yeem tsis tsuas yog kho lub sijhawm qhib thiab teeb tsa cov txheej txheem ntawm cov mortar, txhawm rau kho lub sijhawm ua haujlwm ntawm lub kaw lus, tab sis tseem tiv thaiv cov khoom siv los ntawm nqus dej ntau dhau thiab ceev heev thiab tiv thaiv cov evaporation. dej, thiaj li los xyuas kom meej qhov maj mam tso dej thaum lub sij hawm hydration ntawm cement. Kev tuav dej ntawm CE feem ntau cuam tshuam nrog CE, viscosity, fineness thiab ambient kub. Cov dej tuav cov nyhuv ntawm CE hloov mortar nyob ntawm qhov nqus dej ntawm lub hauv paus, qhov sib xyaw ntawm cov mortar, thickness ntawm txheej, dej yuav tsum tau, lub sij hawm teem ntawm cov cementing khoom, thiab lwm yam kev tshawb fawb qhia tau hais tias nyob rau hauv lub tiag tiag siv. Ntawm qee cov pobzeb ceramic binders, vim yog cov dej ntxeem tau qhuav yuav sai sai nqus dej ntau ntawm cov slurry, cov cement txheej nyob ze ntawm cov dej hauv substrate ua rau cov dej ntawm cov cement qis dua 30%, uas tsis tsuas yog tsim cov cement. gel nrog lub zog sib txuas ntawm qhov chaw ntawm lub substrate, tab sis kuj yooj yim ua rau tawg thiab dej seepage.

Cov dej yuav tsum tau ntawm mortar system yog ib qho tseem ceeb parameter. Qhov kev xav tau ntawm cov dej hauv paus thiab cov khoom sib xyaw ua ke yog nyob ntawm qhov kev tsim cov mortar, piv txwv li cov khoom siv cementing, aggregate thiab aggregate ntxiv, tab sis kev koom ua ke ntawm CE tuaj yeem kho cov dej xav tau thiab cov khoom pov thawj zoo. Hauv ntau cov khoom siv hauv tsev, CE yog siv los ua cov thickener los kho qhov sib xws ntawm qhov system. Cov nyhuv thickening ntawm CE nyob ntawm qhov degree ntawm polymerization ntawm CE, kev daws concentration, shear rate, kub thiab lwm yam kev mob. CE aqueous tov nrog siab viscosity muaj siab thixotropy. Thaum qhov kub nce, cov qauv gel yog tsim thiab siab thixotropy txaus tshwm sim, uas yog ib qho tseem ceeb ntawm CE.

Qhov sib ntxiv ntawm CE tuaj yeem kho cov cuab yeej rheological ntawm cov khoom siv hauv tsev, txhawm rau txhim kho kev ua haujlwm, kom cov mortar muaj kev ua haujlwm zoo dua, kev ua haujlwm zoo dua los tiv thaiv dai, thiab tsis ua raws li cov cuab yeej tsim kho. Cov khoom no ua rau cov mortar yooj yim rau qib thiab kho.

2.3 Kev ntsuas kev ua tau zoo ntawm cellulose ether hloov mortar

Kev ntsuas kev ua tau zoo ntawm CE hloov mortar feem ntau suav nrog dej tuav, viscosity, daim ntawv cog lus lub zog, thiab lwm yam.

Kev tuav dej yog qhov tseem ceeb ntawm kev ua tau zoo uas cuam tshuam ncaj qha rau kev ua haujlwm ntawm CE hloov mortar. Tam sim no, muaj ntau txoj hauv kev sim ntsuas, tab sis feem ntau ntawm lawv siv lub tshuab nqus tsev twj tso kua mis kom ncaj qha cov dej noo. Piv txwv li, cov teb chaws txawv teb chaws feem ntau siv DIN 18555 (cov qauv kev sim ntawm cov khoom siv cementation mortar), thiab Fabkis aerated pob zeb ua lag luam siv cov ntawv lim. Cov txheej txheem hauv tsev uas muaj cov txheej txheem ntsuas dej tuav tau JC / T 517-2004 (plaster plaster), nws cov hauv paus ntsiab lus thiab kev suav cov qauv thiab cov qauv txawv teb chaws zoo ib yam, tag nrho los ntawm kev txiav txim siab ntawm mortar dej nqus tus nqi hais tias mortar dej tuav.

Viscosity yog lwm qhov tseem ceeb Performance index ncaj qha ntsig txog kev ua haujlwm ntawm CE hloov mortar. Muaj plaub txoj kev ntsuas viscosity feem ntau siv: Brookileld, Hakke, Hoppler thiab rotary viscometer method. Plaub txoj kev siv cov cuab yeej sib txawv, kev daws teeb meem, kev sim ib puag ncig, yog li cov kev daws teeb meem tib yam los ntawm plaub txoj kev tsis zoo ib yam. Nyob rau tib lub sijhawm, cov viscosity ntawm CE txawv nrog qhov kub thiab txias, yog li cov viscosity ntawm tib CE hloov mortar hloov dynamically, uas tseem yog ib qho tseem ceeb rau kev kawm ntawm CE hloov mortar tam sim no.

Daim ntawv cog lus lub zog kuaj yog txiav txim siab raws li cov kev taw qhia ntawm kev siv tshuaj khib nyiab, xws li cov ntawv cog lus ceramic feem ntau xa mus rau "ceramic wall tile adhesive" (JC/T 547-2005), Kev tiv thaiv mortar feem ntau yog xa mus rau "sab nrauv phab ntsa rwb thaiv tsev mortar technical requirements" ( DB 31 / T 366-2006) thiab "sab nrauv phab ntsa rwb thaiv tsev nrog nthuav polystyrene board plaster mortar" (JC / T 993-2006). Nyob rau hauv txawv teb chaws, lub zog nplaum yog tus cwj pwm los ntawm lub zog flexural pom zoo los ntawm Japanese Association of Materials Science (qhov kev ntsuam xyuas tau txais cov prismatic zoo tib yam mortar txiav hauv ob halves nrog qhov loj ntawm 160mm × 40mm × 40mm thiab hloov mortar ua rau cov qauv tom qab kho. , nrog rau kev xeem txoj kev ntawm lub zog flexural ntawm cement mortar).

3. Kev tshawb fawb theoretical kev nce qib ntawm cellulose ether hloov mortar

Kev tshawb fawb theoretical ntawm CE hloov mortar feem ntau tsom rau kev sib cuam tshuam ntawm CE thiab ntau yam khoom hauv mortar system. Kev siv tshuaj lom neeg hauv cov khoom siv cement-raws li hloov kho los ntawm CE tuaj yeem pom tau tias yog CE thiab dej, dej ua haujlwm ntawm cov cement nws tus kheej, CE thiab cement particle sib cuam tshuam, CE thiab cement hydration khoom. Kev sib cuam tshuam ntawm CE thiab cement particles / hydration khoom yog feem ntau manifested nyob rau hauv lub adsorption ntawm CE thiab cement hais.

Kev sib cuam tshuam ntawm CE thiab cov cement particles tau tshaj tawm hauv tsev thiab txawv teb chaws. Piv txwv li, Liu Guanghua et al. ntsuas Zeta lub peev xwm ntawm CE hloov kho cement slurry colloid thaum kawm txog kev ua haujlwm ntawm CE hauv cov dej hauv qab dej uas tsis muaj kev sib cais. Cov txiaj ntsig tau pom tias: Zeta muaj peev xwm (-12.6mV) ntawm cov cement-doped slurry yog me dua li cov cement paste (-21.84mV), qhia tias cov cement hais hauv cement-doped slurry yog coated nrog non-ionic polymer txheej, uas ua rau ob chav hluav taws xob txheej diffusion thinner thiab lub zog repulsive ntawm colloid weaker.

3.1 Retarding theory of cellulose ether modified mortar

Hauv kev kawm theoretical ntawm CE hloov mortar, feem ntau ntseeg tau tias CE tsis tsuas yog muab cov mortar nrog kev ua haujlwm zoo, tab sis kuj txo qis cov dej kub thaum ntxov ntawm cov cement thiab ncua cov txheej txheem hydration dynamic ntawm cov cement.

Cov nyhuv retarding ntawm CE yog feem ntau cuam tshuam nrog nws cov concentration thiab molecular qauv hauv cov ntxhia cementing khoom, tab sis muaj kev sib raug zoo nrog nws qhov hnyav molecular. Nws tuaj yeem pom los ntawm cov txiaj ntsig ntawm cov qauv tshuaj ntawm CE ntawm hydration kinetics ntawm cov cement uas siab dua CE cov ntsiab lus, qhov me me ntawm alkyl hloov qib, qhov loj dua cov ntsiab lus hydroxyl, qhov muaj zog ntawm cov dej ncua sij hawm. Nyob rau hauv cov nqe lus ntawm cov qauv molecular, hydrophilic hloov pauv (xws li, HEC) muaj zog retarding nyhuv tshaj hydrophobic hloov (xws li, MH, HEMC, HMPC).

Los ntawm qhov kev xav ntawm kev sib cuam tshuam ntawm CE thiab cov cement particles, lub retarding mechanism yog manifested nyob rau hauv ob yam. Ntawm qhov tod tes, qhov adsorption ntawm CE molecule ntawm cov khoom siv dej xws li c - s -H thiab Ca(OH) 2 tiv thaiv cov cement mineral hydration ntxiv; Ntawm qhov tod tes, qhov viscosity ntawm pore tov nce vim CE, uas txo cov ions (Ca2+, so42-…). Cov dej num hauv cov kua pore ntxiv retards cov txheej txheem hydration.

CE tsis tsuas yog ncua kev teeb tsa, tab sis tseem ncua cov txheej txheem hardening ntawm cov cement mortar system. Nws pom tias CE cuam tshuam rau hydration kinetics ntawm C3S thiab C3A hauv cement clinker hauv ntau txoj kev. CE feem ntau txo qis cov tshuaj tiv thaiv ntawm C3s acceleration theem, thiab ncua lub sij hawm induction ntawm C3A / CaSO4. Lub retardation ntawm c3s hydration yuav ncua lub hardening txheej txheem ntawm mortar, thaum lub sij hawm ntxiv ntawm induction lub sij hawm ntawm C3A / CaSO4 system yuav ncua qhov chaw ntawm mortar.

3.2 Microstructure ntawm cellulose ether hloov mortar

Cov kev cuam tshuam ntawm CE ntawm microstructure ntawm hloov mortar tau nyiam ntau yam. Nws yog feem ntau yog reflected nyob rau hauv cov nram qab no yam:

Ua ntej, kev tshawb fawb tsom mus rau zaj duab xis tsim mechanism thiab morphology ntawm CE hauv mortar. Txij li thaum CE feem ntau siv nrog lwm cov polymers, nws yog ib qho tseem ceeb kev tshawb fawb tsom kom paub qhov txawv ntawm nws lub xeev los ntawm lwm yam polymers nyob rau hauv mortar.

Qhov thib ob, cov txiaj ntsig ntawm CE ntawm microstructure ntawm cov khoom siv cement hydration kuj yog ib qho kev tshawb fawb tseem ceeb. Raws li tuaj yeem pom los ntawm zaj duab xis tsim lub xeev ntawm CE rau cov khoom siv dej, cov khoom siv dej tsim cov qauv txuas ntxiv ntawm qhov sib txuas ntawm cE txuas nrog cov khoom siv dej sib txawv. Xyoo 2008, K.Pen et al. siv isothermal calorimetry, thermal tsom xam, FTIR, SEM thiab BSE los kawm cov txheej txheem lignification thiab hydration khoom ntawm 1% PVAA, MC thiab HEC hloov mortar. Cov txiaj ntsig tau pom tias txawm hais tias cov polymer ncua qhov pib hydration degree ntawm cov cement, nws tau pom cov qauv dej zoo dua ntawm 90 hnub. Tshwj xeeb, MC kuj cuam tshuam rau cov crystal morphology ntawm Ca(OH)2. Cov pov thawj ncaj qha yog tias tus choj ua haujlwm ntawm polymer tau kuaj pom nyob rau hauv cov txheej txheem muaju, MC ua lub luag haujlwm hauv kev sib txuas cov pob zeb, txo cov kab nrib pleb thiab ntxiv dag zog rau microstructure.

Lub microstructure evolution ntawm CE nyob rau hauv mortar kuj tau nyiam heev. Piv txwv li, Jenni siv ntau yam kev tshuaj ntsuam xyuas los kawm txog kev sib cuam tshuam ntawm cov ntaub ntawv hauv cov khoom siv polymer, sib txuas cov kev sim ntau thiab zoo los tsim kho tag nrho cov txheej txheem ntawm mortar tshiab sib tov rau hardening, suav nrog polymer zaj duab xis tsim, cement hydration thiab dej tsiv teb tsaws.

Tsis tas li ntawd, lub micro-kev tshuaj xyuas ntawm cov ntsiab lus sib txawv ntawm lub sijhawm sib txawv hauv cov txheej txheem mortar txoj kev loj hlob, thiab tsis tuaj yeem nyob hauv qhov chaw los ntawm cov tshuaj khib sib xyaw kom tawv nqaij ntawm tag nrho cov txheej txheem ntawm kev soj ntsuam tas li ntawm micro-tam sim no. Yog li ntawd, nws yog ib qho tsim nyog los ua ke tag nrho cov kev sim ntau yam los txheeb xyuas qee theem tshwj xeeb thiab taug qab cov txheej txheem tsim microstructure ntawm cov theem tseem ceeb. Hauv Suav teb, Qian Baowei, Ma Baoguo et al. ncaj qha piav qhia txog cov txheej txheem hydration los ntawm kev siv cov resistivity, kub ntawm hydration thiab lwm yam kev sim. Txawm li cas los xij, vim muaj qee qhov kev sim thiab tsis ua kom muaj kev tiv thaiv thiab kub ntawm hydration nrog lub microstructure ntawm ntau lub sijhawm cov ntsiab lus, tsis muaj kev tshawb fawb txog kev sib raug zoo. Feem ntau, txog rau tam sim no, tsis tau muaj qhov ncaj qha txhais tau hais tias ntau thiab zoo piav qhia txog qhov sib txawv ntawm polymer microstructure hauv mortar.

3.3 Kawm txog cellulose ether hloov nyias txheej mortar

Txawm hais tias tib neeg tau ua ntau qhov kev tshawb fawb thiab theoretical ntawm daim ntawv thov CE hauv cov cement mortar. Tab sis nws yuav tsum tau them sai sai rau yog tias CE hloov mortar nyob rau hauv txhua txhua hnub qhuav sib tov mortar (xws li cib binder, putty, nyias txheej plastering mortar, thiab lwm yam) yog siv nyob rau hauv daim ntawv ntawm nyias txheej mortar, qhov tshwj xeeb qauv no feem ntau yog nrog. los ntawm mortar ceev dej poob teeb meem.

Piv txwv li, ceramic pobzeb bonding mortar yog ib txheej nyias txheej mortar (cov txheej nyias nyias CE hloov mortar qauv ntawm ceramic pobzeb bonding agent), thiab nws cov txheej txheem hydration tau kawm hauv tsev thiab txawv teb chaws. Hauv Suav teb, Coptis rhizoma siv ntau hom thiab ntau npaum li cas ntawm CE los txhim kho kev ua tau zoo ntawm cov nplais pobzeb sib txuas mortar. X-ray txoj kev tau siv los xyuas kom meej tias cov hydration degree ntawm cov cement ntawm qhov sib txuas ntawm cov cement mortar thiab ceramic pobzeb tom qab sib xyaw CE tau nce. Los ntawm kev soj ntsuam qhov sib txuas nrog lub tshuab tsom, nws pom tias cov cement-bridge zog ntawm cov pobzeb ceramic feem ntau tau txhim kho los ntawm kev sib xyaw CE paste es tsis txhob ntom. Piv txwv li, Jenni tau pom kev txhawb nqa ntawm polymer thiab Ca (OH) 2 nyob ze ntawm qhov chaw. Jenni ntseeg hais tias kev sib koom ua ke ntawm cov cement thiab polymer tsav kev sib cuam tshuam ntawm polymer zaj duab xis tsim thiab cement hydration. Cov yam ntxwv tseem ceeb ntawm CE hloov cov cement mortars piv rau cov cement zoo tib yam yog cov dej-cement piv (feem ntau ntawm lossis siab dua 0. 8), tab sis vim lawv qhov siab / ntim, lawv kuj tawv sai, yog li cov cement hydration feem ntau tsawg dua 30%, ntau dua li ntau tshaj 90% raws li feem ntau cov ntaub ntawv. Hauv kev siv XRD thev naus laus zis los kawm txog kev txhim kho txoj cai ntawm qhov chaw microstructure ntawm cov nplais nplaum nplaum nplaum hauv cov txheej txheem hardening, nws tau pom tias qee cov cement me me tau "hloov" mus rau sab nrauv ntawm cov qauv nrog ziab ntawm qhov pore. daws. Txhawm rau txhawb qhov kev xav no, kev sim ntxiv tau ua tiav siv cov cement ntxhib lossis zoo dua limestone es tsis txhob siv cov cement yav dhau los, uas tau ntxiv kev txhawb nqa los ntawm kev poob qis XRD nqus ntawm txhua tus qauv thiab limestone / silica xuab zeb particle loj faib ntawm qhov kawg hardened. lub cev. Environmental scanning electron microscopy (SEM) tests qhia tias CE thiab PVA migrated thaum lub sij hawm ntub thiab qhuav, thaum roj hmab emulsions tsis tau. Raws li qhov no, nws kuj tau tsim cov qauv tsis muaj pov thawj hydration ntawm nyias txheej CE hloov mortar rau ceramic pobzeb binder.

Cov ntaub ntawv cuam tshuam tsis tau tshaj tawm yuav ua li cas cov txheej txheem txheej txheej hydration ntawm polymer mortar yog nqa tawm hauv cov txheej txheem nyias, thiab tsis muaj qhov sib txawv ntawm cov khoom sib txawv ntawm cov polymers nyob rau hauv mortar txheej tau pom thiab ntsuas los ntawm ntau txoj kev. Obviously, lub hydration mechanism thiab microstructure tsim mechanism ntawm CE-mortar system nyob rau hauv cov xwm txheej ntawm cov dej sai sai yog qhov txawv ntawm cov mortar uas twb muaj lawm. Kev kawm txog cov txheej txheem hydration tshwj xeeb thiab microstructure tsim mechanism ntawm nyias txheej CE hloov mortar yuav txhawb kev siv tshuab ntawm txheej txheej CE hloov mortar, xws li sab nrauv phab ntsa plastering mortar, putty, sib koom mortar thiab lwm yam.

4. Muaj teeb meem

4.1 Kev cuam tshuam ntawm qhov kub thiab txias ntawm cellulose ether hloov mortar

CE kev daws teeb meem ntawm ntau hom yuav gel ntawm lawv qhov kub thiab txias, cov txheej txheem gel yog thim rov qab. Lub reversible thermal gelation ntawm CE yog tshwj xeeb heev. Hauv ntau cov khoom siv cement, qhov tseem ceeb ntawm kev siv cov viscosity ntawm CE thiab cov dej tuav thiab lubrication, thiab cov viscosity thiab gel kub muaj kev sib raug zoo, nyob rau hauv cov gel kub, qhov kub thiab txias, qhov viscosity ntawm CE ntau dua, qhov zoo dua cov dej tuav tau zoo.

Nyob rau tib lub sijhawm, solubility ntawm ntau hom CE ntawm qhov sib txawv ntawm qhov kub thiab txias tsis zoo ib yam. Xws li methyl cellulose soluble hauv dej txias, insoluble hauv dej kub; Methyl hydroxyethyl cellulose yog soluble hauv dej txias, tsis yog dej kub. Tab sis thaum lub aqueous tov ntawm methyl cellulose thiab methyl hydroxyethyl cellulose yog rhuab, methyl cellulose thiab methyl hydroxyethyl cellulose yuav precipitate. Methyl cellulose precipitated ntawm 45 ~ 60 ℃, thiab sib xyaw etherized methyl hydroxyethyl cellulose precipitated thaum kub nce mus rau 65 ~ 80 ℃ thiab kub poob, precipitated re yaj. Hydroxyethyl cellulose thiab sodium hydroxyethyl cellulose yog soluble hauv dej ntawm qhov kub thiab txias.

Hauv kev siv CE tiag tiag, tus kws sau ntawv kuj pom tias cov dej tuav lub peev xwm ntawm CE txo qis sai ntawm qhov kub thiab txias (5 ℃), uas feem ntau cuam tshuam txog kev poob qis ntawm kev ua haujlwm thaum lub caij ntuj no, thiab CE yuav tsum tau ntxiv. . Yog vim li cas rau qhov tshwm sim no tsis meej tam sim no. Kev tsom xam tuaj yeem tshwm sim los ntawm kev hloov pauv ntawm solubility ntawm qee qhov CE hauv cov dej kub uas tsis tshua muaj siab, uas yuav tsum tau ua kom ntseeg tau tias kev tsim kho zoo nyob rau lub caij ntuj no.

4.2 Npuas thiab tshem tawm ntawm cellulose ether

CE feem ntau qhia txog ntau cov npuas. Ntawm qhov tod tes, cov npuas me me thiab ruaj khov yog pab tau rau kev ua haujlwm ntawm mortar, xws li kev txhim kho lub constructability ntawm mortar thiab txhim kho cov Frost tsis kam thiab durability ntawm mortar. Hloov chaw, cov npuas loj dua degrade lub mortar's Frost kuj thiab durability.

Nyob rau hauv cov txheej txheem ntawm mortar tov nrog dej, lub mortar yog nplawm, thiab cov huab cua yog coj mus rau hauv lub tshiab sib tov mortar, thiab cov huab cua yog qhwv los ntawm ntub mortar los ua npuas. Feem ntau, nyob rau hauv cov xwm txheej uas tsis tshua muaj viscosity ntawm cov tshuaj, cov npuas tsim los ntawm buoyancy thiab maj mus rau saum npoo ntawm cov tshuaj. Cov npuas khiav tawm ntawm qhov chaw mus rau sab nraud huab cua, thiab cov yeeb yaj kiab ua kua txav mus rau saum npoo yuav tsim qhov sib txawv vim qhov kev ua ntawm lub ntiajteb txawj nqus. Lub thickness ntawm zaj duab xis yuav ua thinner nrog lub sij hawm, thiab thaum kawg cov npuas yuav tawg. Txawm li cas los xij, vim yog qhov siab viscosity ntawm cov tshuaj khib nyiab tshiab tom qab ntxiv CE, qhov nruab nrab ntawm cov kua dej hauv cov kua zaj duab xis yog qeeb, yog li cov kua zaj duab xis tsis yooj yim los ua nyias; Nyob rau tib lub sijhawm, qhov nce ntawm mortar viscosity yuav ua rau qeeb ntawm qhov diffusion ntawm surfactant molecules, uas muaj txiaj ntsig zoo rau kev ua npuas ncauj. Qhov no ua rau ntau cov npuas nkag mus rau hauv lub mortar kom nyob twj ywm hauv lub mortar.

Nto nro thiab interfacial nro ntawm aqueous tov culminating Al hom CE ntawm 1% huab hwm coj concentration ntawm 20 ℃. CE muaj cua nkag rau ntawm cov cement mortar. Cov huab cua entraining nyhuv ntawm CE muaj qhov tsis zoo rau cov neeg kho tshuab lub zog thaum cov npuas loj tau qhia.

Lub defoamer hauv mortar tuaj yeem cuam tshuam cov npuas tsim los ntawm kev siv CE, thiab rhuav tshem cov npuas uas tau tsim. Nws cov txheej txheem ua haujlwm yog: tus neeg sawv cev defoaming nkag mus rau hauv cov yeeb yaj kiab ua kua, txo cov viscosity ntawm cov kua, tsim cov kev sib txuas tshiab nrog cov viscosity qis, ua rau cov kua zaj duab xis poob nws elasticity, accelerates cov txheej txheem ntawm cov kua exudation, thiab thaum kawg ua kua zaj duab xis. nyias thiab tawg. Cov hmoov defoamer tuaj yeem txo cov roj cov ntsiab lus ntawm cov tshuaj khib nyiab tshiab, thiab muaj cov hydrocarbons, stearic acid thiab nws cov ester, trietyl phosphate, polyethylene glycol los yog polysiloxane adsorbed ntawm cov cab kuj inorganic. Tam sim no, cov hmoov defoamer siv nyob rau hauv qhuav mix mortar feem ntau yog polyols thiab polysiloxane.

Txawm hais tias nws tau tshaj tawm tias ntxiv rau kev kho cov ntsiab lus npuas, daim ntawv thov ntawm defoamer tuaj yeem txo qis, tab sis ntau hom defoamer kuj muaj teeb meem sib xws thiab qhov kub thiab txias hloov thaum siv ua ke nrog CE, cov no yog cov txheej txheem yooj yim uas yuav tsum tau daws hauv. kev siv CE hloov mortar zam.

4.3 Compatibility ntawm cellulose ether thiab lwm yam ntaub ntawv nyob rau hauv mortar

CE feem ntau yog siv ua ke nrog lwm cov khoom siv hauv cov khoom sib xyaw qhuav, xws li defoamer, dej txo tus neeg sawv cev, nplaum hmoov, thiab lwm yam. Cov khoom siv no ua lub luag haujlwm sib txawv hauv mortar feem. Txhawm rau kawm txog kev sib raug zoo ntawm CE nrog rau lwm cov khoom sib xyaw yog lub hauv paus ntawm kev siv tau zoo ntawm cov khoom no.

Qhuav mix mortar feem ntau siv cov dej txo cov neeg ua haujlwm yog: casein, lignin series dej txo tus neeg saib xyuas, naphthalene series dej txo tus neeg saib xyuas, melamine formaldehyde condensation, polycarboxylic acid. Casein yog ib qho zoo heev superplasticizer, tshwj xeeb tshaj yog rau nyias mortars, tab sis vim nws yog ib yam khoom ntuj, qhov zoo thiab tus nqi feem ntau hloov. Lignin dej-txo cov tshuaj muaj xws li sodium lignosulfonate (ntoo sodium), ntoo calcium, ntoo magnesium. Naphthalene series dej reducer feem ntau siv Lou. Naphthalene sulfonate formaldehyde condensates, melamine formaldehyde condensates yog superplasticizers zoo, tab sis cov nyhuv ntawm nyias mortar yog txwv. Polycarboxylic acid yog cov cuab yeej tsim tshiab nrog kev ua haujlwm siab thiab tsis muaj formaldehyde emission. Vim hais tias CE thiab ntau naphthalene series superplasticizer yuav ua rau coagulation ua kom cov pob zeb sib tov poob ua haujlwm, yog li nws yuav tsum xaiv cov non-naphthalene series superplasticizer hauv engineering. Txawm hais tias muaj kev tshawb fawb txog kev sib xyaw ntawm CE hloov mortar thiab sib txawv admixtures, tseem muaj ntau qhov kev nkag siab tsis zoo hauv kev siv vim muaj ntau yam admixtures thiab CE thiab ob peb cov kev tshawb fawb ntawm kev sib cuam tshuam mechanism, thiab ntau qhov kev ntsuam xyuas yuav tsum tau ua. optimize nws.

5. Cov lus xaus

Lub luag hauj lwm ntawm CE nyob rau hauv mortar yog feem ntau xav txog nyob rau hauv lub zoo heev dej retention muaj peev xwm, lub hwj chim ntawm lub sib xws thiab thixotropic zog ntawm mortar thiab kev kho ntawm rheological zog. Ntxiv nrog rau kev muab cov mortar ua haujlwm tau zoo, CE tuaj yeem txo cov dej kub thaum ntxov ntawm cov cement thiab ncua cov txheej txheem hydration dynamic ntawm cov cement. Cov kev ntsuas kev ua tau zoo ntawm cov mortar sib txawv raws li qhov sib txawv ntawm kev thov.

Ntau cov kev tshawb fawb ntawm microstructure ntawm CE hauv mortar xws li zaj duab xis tsim mechanism thiab zaj duab xis tsim morphology tau ua nyob txawv teb chaws, tab sis txog rau tam sim no, tsis muaj kev ncaj qha txhais tau hais tias ntau thiab zoo piav qhia txog qhov muaj qhov sib txawv ntawm polymer microstructure hauv mortar. .

CE hloov mortar yog siv nyob rau hauv daim ntawv ntawm nyias txheej mortar nyob rau hauv txhua txhua hnub qhuav sib tov mortar (xws li lub ntsej muag cib binder, putty, nyias txheej mortar, thiab lwm yam). Cov qauv tshwj xeeb no feem ntau yog nrog rau qhov teeb meem ntawm kev poob dej sai ntawm mortar. Tam sim no, kev tshawb fawb tseem ceeb tsom mus rau lub ntsej muag cib binder, thiab muaj ob peb txoj kev tshawb fawb ntawm lwm hom txheej nyias nyias CE hloov mortar.

Yog li ntawd, nyob rau hauv lub neej yav tom ntej, nws yog ib qho tsim nyog yuav tsum tau ceev cov kev tshawb fawb ntawm txheej txheej hydration mechanism ntawm cellulose ether hloov mortar nyob rau hauv lub nyias txheej qauv thiab spatial faib txoj cai ntawm polymer nyob rau hauv lub mortar txheej nyob rau hauv cov kev mob ntawm cov dej sai sai. Hauv kev siv tswv yim, kev cuam tshuam ntawm cellulose ether hloov mortar ntawm qhov kub thiab txias thiab nws compatibility nrog rau lwm yam additives yuav tsum tau txiav txim siab tag nrho. Cov kev tshawb fawb ntsig txog kev ua haujlwm yuav txhawb nqa kev siv thev naus laus zis ntawm CE hloov mortar xws li sab nrauv phab ntsa plastering mortar, putty, sib koom mortar thiab lwm cov txheej nyias nyias.