Cellulose ether
Cellulose ether yog cov ntsiab lus dav dav rau cov khoom lag luam uas tsim los ntawm cov tshuaj tiv thaiv ntawm alkali cellulose thiab etherifying tus neeg sawv cev nyob rau hauv qee yam mob. Alkali cellulose yog hloov los ntawm cov neeg ua haujlwm sib txawv kom tau txais cov cellulose ethers sib txawv. Raws li cov khoom ionization ntawm cov khoom hloov, cellulose ethers tuaj yeem muab faib ua ob pawg: ionic (xws li carboxymethyl cellulose) thiab non-ionic (xws li methyl cellulose). Raws li hom kev hloov pauv, cellulose ether tuaj yeem muab faib ua monoether (xws li methyl cellulose) thiab sib xyaw ether (xws li hydroxypropyl methyl cellulose). Raws li kev sib txawv solubility, nws tuaj yeem muab faib ua dej-soluble (xws li hydroxyethyl cellulose) thiab organic solvent-soluble (xws li ethyl cellulose), thiab lwm yam. Cov tshuaj khib nyiab qhuav yog dej-soluble cellulose, thiab dej-soluble cellulose yog muab faib ua hom instant thiab nto kho ncua sij hawm dissolution hom.
Lub mechanism ntawm kev txiav txim ntawm cellulose ether nyob rau hauv mortar yog raws li nram no:
(1) Tom qab cov cellulose ether nyob rau hauv lub mortar yog yaj nyob rau hauv dej, qhov zoo thiab niaj hnub faib ntawm cov cementitious cov ntaub ntawv nyob rau hauv lub system yog guaranteed vim lub nto nto, thiab cellulose ether, raws li ib tug tiv thaiv colloid, "wraps" cov khoom. cov khoom thiab Ib txheej ntawm lubricating zaj duab xis yog tsim rau ntawm nws sab nrauv, uas ua rau cov mortar system ruaj khov, thiab tseem txhim kho cov kua dej ntawm cov mortar thaum lub sij hawm sib tov thiab smoothness ntawm kev tsim kho.
(2) Vim nws tus kheej cov qauv molecular, cov tshuaj cellulose ether ua rau cov dej hauv mortar tsis yooj yim ploj, thiab maj mam tso tawm rau lub sijhawm ntev, ua rau cov mortar nrog dej zoo thiab ua haujlwm tau zoo.
1. Methylcellulose (MC)
Tom qab cov paj rwb refined yog kho nrog alkali, cellulose ether yog tsim los ntawm ib tug series ntawm cov tshuaj tiv thaiv nrog methane chloride ua etherification tus neeg sawv cev. Feem ntau, qhov degree ntawm kev hloov pauv yog 1.6 ~ 2.0, thiab cov solubility kuj txawv nrog ntau qib kev hloov pauv. Nws belongs rau non-ionic cellulose ether.
(1) Methylcellulose yog soluble hauv dej txias, thiab nws yuav nyuaj rau yaj hauv dej kub. Nws cov tshuaj aqueous yog ruaj khov nyob rau hauv thaj tsam ntawm pH = 3 ~ 12. Nws muaj kev sib raug zoo nrog cov hmoov txhuv nplej siab, cov pos hniav, thiab lwm yam thiab ntau surfactants. Thaum qhov kub nce mus txog qhov kub thiab txias, gelation tshwm sim.
(2) Cov dej tuav ntawm methyl cellulose nyob ntawm nws cov nyiaj ntxiv, viscosity, particle fineness thiab dissolution tus nqi. Feem ntau, yog tias qhov sib ntxiv yog qhov loj, qhov zoo me me, thiab cov viscosity loj, cov dej tuav tau siab. Ntawm lawv, qhov sib ntxiv muaj qhov cuam tshuam loj tshaj plaws ntawm cov dej tuav tus nqi, thiab qib ntawm viscosity tsis ncaj qha mus rau theem ntawm cov dej tuav tus nqi. Tus nqi dissolution feem ntau yog nyob ntawm qhov kev hloov kho saum npoo ntawm cellulose hais thiab particle fineness. Ntawm cov cellulose ethers saum toj no, methyl cellulose thiab hydroxypropyl methyl cellulose muaj cov dej tuav ntau dua.
(3) Kev hloov ntawm qhov kub thiab txias yuav cuam tshuam rau cov dej tuav tus nqi ntawm methyl cellulose. Feem ntau, qhov kub thiab txias dua, qhov dej khaws cia tsis zoo. Yog hais tias lub mortar kub siab tshaj 40 ° C, cov dej tuav ntawm methyl cellulose yuav txo qis, cuam tshuam rau kev tsim kho ntawm mortar.
(4) Methyl cellulose muaj qhov cuam tshuam loj rau kev tsim kho thiab adhesion ntawm mortar. Qhov "adhesion" ntawm no yog hais txog cov nplaum nplaum ntawm tus neeg ua haujlwm cov cuab yeej siv thiab cov phab ntsa substrate, uas yog, shear resistance ntawm lub mortar. Lub adhesiveness yog siab, shear resistance ntawm lub mortar yog loj, thiab lub zog yuav tsum tau los ntawm cov neeg ua hauj lwm nyob rau hauv tus txheej txheem ntawm kev siv kuj loj, thiab kev tsim kho ntawm lub mortar yog tsis zoo. Methyl cellulose adhesion yog nyob rau theem nrab hauv cellulose ether cov khoom.
2. Hydroxypropylmethylcellulose (HPMC)
Hydroxypropyl methylcellulose yog ib hom cellulose uas nws cov zis thiab kev noj tau nce zuj zus nyob rau xyoo tas los no. Nws yog non-ionic cellulose tov ether ua los ntawm refined paj rwb tom qab alkalization, siv propylene oxide thiab methyl chloride ua etherification tus neeg sawv cev, los ntawm ib tug series ntawm cov tshuaj tiv thaiv. Qhov kev hloov pauv feem ntau yog 1.2 ~ 2.0. Nws cov khoom sib txawv vim qhov sib txawv ntawm cov ntsiab lus methoxyl thiab hydroxypropyl cov ntsiab lus.
(1) Hydroxypropyl methylcellulose yog yooj yim soluble nyob rau hauv dej txias, thiab nws yuav ntsib teeb meem nyob rau hauv dissolving nyob rau hauv dej kub. Tab sis nws qhov kub thiab txias hauv dej kub yog siab dua li ntawm methyl cellulose. Lub solubility hauv dej txias kuj zoo heev piv nrog methyl cellulose.
(2) Lub viscosity ntawm hydroxypropyl methylcellulose muaj feem xyuam rau nws qhov hnyav molecular, thiab qhov loj dua qhov hnyav molecular, qhov viscosity siab dua. Kub kuj cuam tshuam rau nws cov viscosity, thaum kub nce, viscosity txo. Txawm li cas los xij, nws cov viscosity siab muaj qhov kub qis dua li methyl cellulose. Nws cov tshuaj yog ruaj khov thaum khaws cia ntawm chav tsev kub.
(3) Cov dej tuav ntawm hydroxypropyl methylcellulose nyob ntawm nws qhov sib ntxiv, viscosity, thiab lwm yam, thiab nws cov dej tuav tus nqi nyob rau hauv tib qhov sib ntxiv yog siab dua li ntawm methyl cellulose.
(4) Hydroxypropyl methylcellulose ruaj khov rau cov kua qaub thiab alkali, thiab nws cov tshuaj aqueous yog ruaj khov nyob rau hauv thaj tsam ntawm pH = 2 ~ 12. Caustic dej qab zib thiab txiv qaub dej tsis tshua muaj txiaj ntsig rau nws qhov kev ua tau zoo, tab sis alkali tuaj yeem ua kom nws tawg thiab ua kom nws cov viscosity. Hydroxypropyl methylcellulose yog ruaj khov rau cov ntsev ntau, tab sis thaum lub concentration ntawm ntsev tov yog siab, lub viscosity ntawm hydroxypropyl methylcellulose tov nyhav nce.
(5) Hydroxypropyl methylcellulose tuaj yeem sib xyaw nrog cov dej-soluble polymer compounds los ua ib qho kev daws teeb meem thiab siab dua viscosity. Xws li polyvinyl cawv, starch ether, zaub pos hniav, thiab lwm yam.
(6) Hydroxypropyl methylcellulose muaj enzyme zoo dua li methylcellulose, thiab nws cov tshuaj tsis tshua muaj peev xwm degraded los ntawm enzymes dua methylcellulose.
(7) Qhov adhesion ntawm hydroxypropyl methylcellulose rau mortar siv yog siab dua li ntawm methylcellulose.
3. Hydroxyethyl cellulose (HEC)
Nws yog tsim los ntawm refined paj rwb kho nrog alkali, thiab reacted nrog ethylene oxide raws li etherification tus neeg sawv cev nyob rau hauv lub xub ntiag ntawm acetone. Qhov kev hloov pauv feem ntau yog 1.5 ~ 2.0. Nws muaj zog hydrophilicity thiab yooj yim rau nqus noo noo
(1) Hydroxyethyl cellulose yog soluble hauv dej txias, tab sis nws nyuaj rau yaj hauv dej kub. Nws cov tshuaj yog ruaj khov ntawm qhov kub thiab txias yam tsis muaj gelling. Nws tuaj yeem siv tau ntev hauv qhov kub thiab txias hauv mortar, tab sis nws cov dej tuav qis dua li ntawm methyl cellulose.
(2) Hydroxyethyl cellulose ruaj khov rau cov kua qaub thiab alkali. Alkali tuaj yeem ua kom nrawm nrawm rau nws qhov kev sib cais thiab ua kom nws cov viscosity me ntsis. Nws dispersibility hauv dej yog me ntsis phem dua li ntawm methyl cellulose thiab hydroxypropyl methyl cellulose. .
(3) Hydroxyethyl cellulose muaj kev ua haujlwm zoo los tiv thaiv mortar, tab sis nws muaj sijhawm ntev dua rau cov cement.
(4) Kev ua tau zoo ntawm hydroxyethyl cellulose ua los ntawm qee lub tuam txhab hauv tsev yog pom tseeb qis dua li ntawm methyl cellulose vim nws cov ntsiab lus dej siab thiab cov hmoov tshauv siab.
4. Carboxymethyl cellulose (CMC)
Ionic cellulose ether yog tsim los ntawm ntuj fibers (paj rwb, thiab lwm yam) tom qab kev kho alkali, siv sodium monochloroacetate ua tus neeg sawv cev etherification, thiab tau txais kev kho cov tshuaj tiv thaiv. Qib ntawm kev hloov pauv feem ntau yog 0.4 ~ 1.4, thiab nws qhov kev ua tau zoo cuam tshuam los ntawm qib hloov pauv.
(1) Carboxymethyl cellulose yog hygroscopic ntau dua, thiab nws yuav muaj dej ntau dua thaum khaws cia rau hauv cov xwm txheej.
(2) Carboxymethyl cellulose aqueous tov yuav tsis tsim gel, thiab viscosity yuav txo nrog qhov kub thiab txias. Thaum qhov kub siab tshaj 50 ° C, viscosity yog irreversible.
(3) Nws ruaj khov heev cuam tshuam los ntawm pH. Feem ntau, nws tuaj yeem siv rau hauv gypsum-raws li mortar, tab sis tsis yog hauv cov cement-based mortar. Thaum alkaline heev, nws poob viscosity.
(4) Nws cov dej tuav tau qis dua li ntawm methyl cellulose. Nws muaj cov nyhuv retarding ntawm gypsum-raws li mortar thiab txo nws lub zog. Txawm li cas los xij, tus nqi ntawm carboxymethyl cellulose yog qis dua li ntawm methyl cellulose.
Redispersible polymer roj hmab hmoov
Redispersible roj hmab hmoov yog ua tiav los ntawm cov tshuaj tsuag kom qhuav ntawm tshwj xeeb polymer emulsion. Nyob rau hauv cov txheej txheem ntawm kev ua, kev tiv thaiv colloid, anti-caking tus neeg saib xyuas, thiab lwm yam ua indispensable additives. Cov hmoov roj hmab qhuav yog qee qhov sib txawv ntawm 80 ~ 100mm sib sau ua ke. Cov khoom no yog soluble nyob rau hauv dej thiab tsim ib tug ruaj khov dispersion me ntsis loj dua cov thawj emulsion hais. Qhov no dispersion yuav tsim ib zaj duab xis tom qab lub cev qhuav dej thiab qhuav. Cov zaj duab xis no yog irreversible raws li qhov dav emulsion zaj duab xis tsim, thiab yuav tsis redisperse thaum nws ntsib dej. Dispersions.
Redispersible roj hmab hmoov tuaj yeem muab faib ua: styrene-butadiene copolymer, tertiary carbonic acid ethylene copolymer, ethylene-acetate acetic acid copolymer, thiab raws li qhov no, silicone, vinyl laurate, thiab lwm yam yog grafted los txhim kho kev ua haujlwm. Cov kev hloov pauv sib txawv ua rau cov hmoov roj hmab rov qab muaj cov khoom sib txawv xws li dej tsis kam, alkali tsis kam, huab cua tsis kam thiab yoog raws. Muaj vinyl laurate thiab silicone, uas tuaj yeem ua rau cov hmoov roj hmab muaj cov dej zoo. Highly branched vinyl tertiary carbonate nrog tsawg Tg tus nqi thiab zoo saj zawg zog.
Thaum cov hmoov roj hmab no siv rau hauv mortar, lawv txhua tus muaj qhov cuam tshuam ncua sij hawm ntawm cov cement, tab sis cov nyhuv qeeb yog me dua li ntawm kev siv ncaj qha ntawm cov emulsions zoo sib xws. Hauv kev sib piv, styrene-butadiene muaj qhov cuam tshuam loj tshaj plaws, thiab ethylene-vinyl acetate muaj qhov cuam tshuam tsawg tshaj plaws. Yog tias qhov ntau npaum li cas me me, cov nyhuv ntawm kev txhim kho kev ua haujlwm ntawm mortar tsis pom tseeb.
Polypropylene fibers
Polypropylene fiber ntau yog ua los ntawm polypropylene ua raw khoom thiab tsim nyog tus nqi ntawm kev hloov kho. Txoj kab uas hla ntawm fiber ntau yog 40 microns, lub zog tensile yog 300 ~ 400mpa, elastic modulus yog ≥3500mpa, thiab qhov kawg elongation yog 15 ~ 18%. Nws cov yam ntxwv ua haujlwm:
(1) Polypropylene fibers yog uniformly faib nyob rau hauv peb-dimensional random cov lus qhia nyob rau hauv lub mortar, tsim ib tug network reinforcement system. Yog tias 1 kg ntawm polypropylene fiber ntau ntxiv rau txhua tuj ntawm mortar, tuaj yeem tau txais ntau dua 30 lab monofilament fibers.
(2) Ntxiv polypropylene fiber ntau rau hauv mortar tuaj yeem txo qhov shrinkage tawg ntawm mortar hauv lub xeev yas. Seb cov kab nrib pleb no puas pom los tsis pom. Thiab nws tuaj yeem txo cov ntshav los ntshav thiab sib sau ua ke ntawm cov mortar tshiab.
(3) Rau mortar hardened lub cev, polypropylene fiber ntau tuaj yeem txo tus naj npawb ntawm deformation tawg. Ntawd yog, thaum lub mortar hardening lub cev tsim kev ntxhov siab vim deformation, nws tuaj yeem tiv taus thiab xa cov kev ntxhov siab. Thaum lub mortar hardening lub cev tawg, nws muaj peev xwm passivate qhov kev nyuaj siab concentration nyob rau hauv lub ntsis ntawm lub tawg thiab txwv qhov tawg expansion.
(4) Kev ua haujlwm zoo ntawm polypropylene fibers hauv mortar ntau lawm yuav dhau los ua teeb meem nyuaj. Cov khoom sib xyaw, hom fiber ntau thiab ntau npaum li cas, qhov sib piv ntawm mortar thiab nws cov txheej txheem tsis ua haujlwm yuav dhau los ua qhov tseem ceeb cuam tshuam rau kev tawg.
air entraining tus neeg sawv cev
Air-entraining tus neeg sawv cev yog ib hom surfactant uas tuaj yeem tsim cov huab cua ruaj khov hauv cov pob zeb tshiab lossis mortar los ntawm kev siv lub cev. Feem ntau suav nrog: rosin thiab nws cov thermal polymers, non-ionic surfactants, alkylbenzene sulfonates, lignosulfonates, carboxylic acids thiab lawv cov ntsev, thiab lwm yam.
Cov neeg ua haujlwm huab cua feem ntau siv los npaj plastering mortars thiab masonry mortars. Vim yog qhov sib ntxiv ntawm cov neeg sawv cev ntawm huab cua nkag, qee qhov kev hloov pauv hauv kev ua yeeb yam mortar yuav raug coj los.
(1) Raws li kev nthuav qhia ntawm cov pa npuas, qhov yooj yim thiab kev tsim kho ntawm cov khoom sib xyaw tshiab tuaj yeem nce ntxiv, thiab los ntshav tuaj yeem txo.
(2) Tsuas yog siv tus neeg saib xyuas huab cua yuav txo tau lub zog thiab elasticity ntawm pwm nyob rau hauv mortar. Yog tias tus neeg saib xyuas huab cua nkag mus thiab tus neeg saib xyuas dej txo tau siv ua ke, thiab qhov sib piv yog qhov tsim nyog, tus nqi zog yuav tsis txo.
(3) Nws tuaj yeem txhim kho qhov Frost tsis kam ntawm cov mortar hardened, txhim kho cov impermeability ntawm mortar, thiab txhim kho cov erosion kuj ntawm cov mortar hardened.
(4) Tus neeg saib xyuas huab cua yuav ua rau kom cov huab cua ntawm cov mortar nce ntxiv, uas yuav ua rau kom cov mortar shrinkage, thiab tus nqi shrinkage yuav raug txo kom tsim nyog los ntawm kev ntxiv cov dej txo tus neeg sawv cev.
Txij li tus nqi ntawm cov khoom siv cua nkag tau ntxiv yog tsawg heev, feem ntau tsuas yog suav rau ob peb kaum-txhiab ntawm tag nrho cov khoom siv cementitious, nws yuav tsum tau ua kom ntseeg tau tias nws raug ntsuas kom raug thiab sib xyaw rau hauv cov khoom siv khib nyiab; yam xws li stirring txoj kev thiab stirring lub sij hawm yuav cuam tshuam rau huab cua-entraining tus nqi. Yog li ntawd, nyob rau hauv lub tam sim no domestic ntau lawm thiab kev tsim kho tej yam kev mob, ntxiv huab cua-entraining neeg sawv cev rau lub mortar yuav tsum tau ntau ntawm kev sim ua hauj lwm.
thaum ntxov zog tus neeg sawv cev
Siv los txhim kho lub zog thaum ntxov ntawm pob zeb thiab mortar, sulfate thaum ntxov muaj zog cov neeg ua haujlwm feem ntau yog siv, feem ntau suav nrog sodium sulfate, sodium thiosulfate, aluminium sulfate thiab potassium aluminium sulfate.
Feem ntau, anhydrous sodium sulfate yog siv dav, thiab nws qhov ntau npaum li cas tsawg thiab cov nyhuv ntawm lub zog thaum ntxov yog qhov zoo, tab sis yog tias qhov ntau npaum li cas, nws yuav ua rau nthuav dav thiab tawg rau theem tom qab, thiab tib lub sijhawm, alkali rov qab. yuav tshwm sim, uas yuav cuam tshuam rau cov tsos thiab cov nyhuv ntawm qhov chaw kho kom zoo nkauj txheej.
Calcium formate kuj yog ib qho tshuaj tiv thaiv kab mob zoo. Nws muaj cov txiaj ntsig zoo thaum ntxov, muaj kev phiv tsawg, kev sib raug zoo nrog lwm cov khoom sib xyaw, thiab ntau yam khoom zoo dua li sulfate thaum ntxov zog, tab sis tus nqi siab dua.
antifreeze
Yog tias lub mortar siv rau qhov kub tsis zoo, yog tias tsis muaj kev tiv thaiv kev tiv thaiv kev tiv thaiv, kev puas tsuaj los ntawm Frost yuav tshwm sim thiab lub zog ntawm lub cev tawv yuav raug rhuav tshem. Antifreeze tiv thaiv kev puas tsuaj los ntawm ob txoj kev tiv thaiv kom khov thiab txhim kho lub zog thaum ntxov ntawm mortar.
Ntawm cov tshuaj tiv thaiv kab mob uas nquag siv, calcium nitrite thiab sodium nitrite muaj cov tshuaj tiv thaiv zoo tshaj plaws. Txij li thaum calcium nitrite tsis muaj cov poov tshuaj thiab sodium ions, nws tuaj yeem txo qhov tshwm sim ntawm alkali aggregate thaum siv hauv pob zeb, tab sis nws txoj haujlwm tsis zoo me ntsis thaum siv hauv mortar, thaum sodium nitrite muaj kev ua haujlwm zoo dua. Antifreeze yog siv ua ke nrog cov neeg sawv cev thaum ntxov thiab cov dej reducer kom tau txais txiaj ntsig zoo. Thaum cov tshuaj khib nyiab qhuav nrog cov tshuaj tua kab mob yog siv rau ntawm qhov ntsuas kub tsis zoo, qhov kub ntawm qhov sib tov yuav tsum tau nce kom tsim nyog, xws li sib tov nrog dej sov.
Yog hais tias tus nqi ntawm cov tshuaj tiv thaiv yog siab dhau lawm, nws yuav txo tau lub zog ntawm lub mortar nyob rau hauv lub tom ntej no theem, thiab cov nto ntawm lub hardened mortar yuav muaj teeb meem xws li alkali rov qab, uas yuav cuam tshuam rau cov tsos thiab cov nyhuv ntawm lub decorating txheej. .
Post lub sij hawm: Jan-16-2023