Cov hom admixtures feem ntau siv hauv tsev qhuav-sib xyaw mortar, lawv cov yam ntxwv ntawm kev ua haujlwm, kev ua haujlwm, thiab lawv lub zog ntawm kev ua haujlwm ntawm cov khoom siv khib nyiab qhuav.Kev txhim kho cov nyhuv ntawm cov dej khaws cia xws li cellulose ether thiab starch ether, redispersible latex hmoov thiab fiber ntau cov ntaub ntawv ntawm kev ua tau zoo ntawm qhuav-siv mortar tau tham emphatically.
Admixtures ua lub luag haujlwm tseem ceeb hauv kev txhim kho kev ua haujlwm ntawm lub tsev qhuav-sib xyaw mortar, tab sis qhov sib ntxiv ntawm cov tshuaj khib nyiab qhuav ua rau cov khoom siv ntawm cov khoom siv khib nyiab qhuav ntau dua li cov tshuaj mortar, uas suav txog ntau dua 40% ntawm cov khoom raug nqi nyob rau hauv qhuav-mixed mortar.Tam sim no, ib feem ntau ntawm cov khoom sib xyaw yog muab los ntawm cov tuam txhab txawv teb chaws, thiab kev siv ntau npaum li cas ntawm cov khoom kuj yog muab los ntawm tus neeg muag khoom.Raws li qhov tshwm sim, tus nqi ntawm cov khoom siv tshuaj khib nyiab qhuav tseem muaj siab, thiab nws yog qhov nyuaj rau kev nyiam cov masonry zoo tib yam thiab plastering mortars nrog ntau qhov ntau thiab dav;Cov khoom lag luam siab kawg yog tswj hwm los ntawm cov tuam txhab txawv teb chaws, thiab cov tuam txhab tsim khoom qhuav sib xyaw muaj cov txiaj ntsig tsawg thiab tsis zoo rau tus nqi;Muaj tsis muaj kev tshawb fawb thiab tsom mus rau kev siv tshuaj, thiab cov qauv txawv teb chaws tau ua raws li qhov muag tsis pom.
Raws li cov laj thawj saum toj no, daim ntawv no tshuaj xyuas thiab sib piv qee cov khoom siv ntawm cov khoom siv uas nquag siv, thiab ntawm lub hauv paus no, kawm txog kev ua haujlwm ntawm cov khoom siv khib nyiab qhuav uas siv cov khoom sib xyaw.
1 dej tuav tus neeg sawv cev
Dej tuav tus neeg saib xyuas yog ib qho tseem ceeb admixture los txhim kho cov dej tuav kev ua tau zoo ntawm cov khoom sib xyaw qhuav, thiab nws kuj yog ib qho tseem ceeb ntawm cov khoom siv los txiav txim seb tus nqi ntawm cov khoom siv khib nyiab qhuav.
1. Hydroxypropyl Methyl Cellulose Ether (HPMC)
Hydroxypropyl methylcellulose yog cov ntsiab lus dav dav rau cov khoom lag luam 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) 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.
2. 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.
3. Hydroxyethylcellulose (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.
Starch ether
Cov hmoov txhuv nplej siab ethers siv hauv mortars yog hloov kho los ntawm ntuj polymers ntawm qee cov polysaccharides.Xws li qos yaj ywm, pob kws, cassava, taum guar thiab hais txog.
1. Hloov cov hmoov txhuv nplej siab
Cov hmoov txhuv nplej siab ether hloov los ntawm qos yaj ywm, pob kws, cassava, thiab lwm yam tau txo qis dej ntau dua li cellulose ether.Vim qhov sib txawv ntawm kev hloov kho, qhov ruaj khov rau cov kua qaub thiab alkali sib txawv.Qee cov khoom tsim nyog siv rau hauv gypsum-raws li mortars, thaum lwm tus tuaj yeem siv rau hauv cov cement-based mortars.Daim ntawv thov cov hmoov txhuv nplej siab ether hauv mortar feem ntau yog siv los ua cov thickener los txhim kho cov cuab yeej tiv thaiv sagging ntawm mortar, txo cov adhesion ntawm cov khib nyiab ntub dej, thiab ua kom lub sijhawm qhib.
Cov hmoov txhuv nplej siab ethers feem ntau siv ua ke nrog cellulose, yog li ntawd cov khoom thiab qhov zoo ntawm ob yam khoom no ntxiv rau ib leeg.Txij li cov hmoov txhuv nplej siab ether cov khoom lag luam pheej yig dua li cellulose ether, daim ntawv thov cov hmoov txhuv nplej siab ether hauv mortar yuav ua rau txo qis ntawm cov nqi ntawm cov tshuaj khib nyiab.
2. Guar cov pos hniav ether
Guar gum ether yog ib hom hmoov txhuv nplej siab ether nrog cov khoom tshwj xeeb, uas tau hloov kho los ntawm cov noob taum ntuj.Feem ntau los ntawm etherification cov tshuaj tiv thaiv ntawm guar gum thiab acrylic functional pawg, ib tug qauv uas muaj 2-hydroxypropyl functional pawg yog tsim, uas yog ib tug polygalactomannose qauv.
(1) Piv nrog cellulose ether, guar gum ether yog ntau soluble hauv dej.Cov khoom ntawm pH guar ethers yog qhov tseem ceeb tsis cuam tshuam.
(2) Nyob rau hauv cov kev mob uas tsis tshua muaj viscosity thiab tsawg npaum li cas, guar pos hniav tuaj yeem hloov cellulose ether hauv qhov sib npaug, thiab muaj cov dej zoo sib xws.Tab sis qhov sib xws, anti-sag, thixotropy thiab lwm yam yog pom tseeb txhim kho.
(3) Nyob rau hauv cov xwm txheej ntawm cov viscosity siab thiab ntau npaum li cas, guar cov pos hniav tsis tuaj yeem hloov cellulose ether, thiab kev sib xyaw siv ntawm ob yuav ua tau zoo dua.
(4) Daim ntawv thov ntawm cov pos hniav hauv gypsum-raws li mortar tuaj yeem txo qhov adhesion thaum lub sij hawm tsim kho thiab ua rau kev tsim kho smoother.Nws tsis muaj qhov cuam tshuam rau lub sijhawm teeb tsa thiab lub zog ntawm gypsum mortar.
3. Hloov cov dej ntxhia dej-retaining thickener
Cov dej-retaining thickener ua los ntawm natural minerals los ntawm kev hloov kho thiab compounding tau siv nyob rau hauv Suav teb.Cov zaub mov tseem ceeb uas siv los npaj cov dej tuav cov thickeners yog: sepiolite, bentonite, montmorillonite, kaolin, thiab lwm yam. Cov zaub mov no muaj qee yam dej tuav thiab thickening zog los ntawm kev hloov kho xws li coupling agents.Hom dej-retaining thickener siv rau mortar muaj cov yam ntxwv hauv qab no.
(1) Nws tuaj yeem txhim kho kev ua tau zoo ntawm cov mortar zoo tib yam, thiab daws cov teeb meem ntawm kev ua haujlwm tsis zoo ntawm cov cement mortar, tsis muaj zog ntawm cov mortar sib xyaw, thiab cov dej tsis zoo.
(2) Cov khoom siv khib nyiab nrog ntau qib sib txawv rau kev lag luam thiab pej xeem vaj tse tuaj yeem tsim.
(3) Cov khoom siv tus nqi qis dua li ntawm cellulose ether thiab starch ether.
(4) Cov dej tuav tau qis dua li ntawm cov organic dej tuav tus neeg sawv cev, cov nqi qhuav ntawm cov tshuaj khib nyiab yog qhov loj dua, thiab qhov cohesiveness yog txo.
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.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.
Post lub sij hawm: Apr-03-2023