Lub npe Suav ntawm HPMC yog hydroxypropyl methylcellulose. Nws yog non-ionic thiab feem ntau siv ua tus neeg sawv cev khaws dej hauv cov mortar qhuav. Nws yog cov khoom siv khaws dej feem ntau siv hauv mortar. Ib qho khoom polysaccharide-based ether tsim los ntawm alkalization thiab etherification. Nws tsis muaj nqi nws tus kheej, tsis cuam tshuam nrog cov ions them hauv cov khoom gelling, thiab muaj kev ua haujlwm ruaj khov. Tus nqi kuj qis dua lwm hom cellulose ethers, yog li nws yog dav siv hauv cov mortar qhuav.
Kev Ua Haujlwm ntawm hydroxypropyl methylcellulose: Nws tuaj yeem ua rau cov mortar sib xyaw tshiab tuab kom muaj qee qhov viscosity ntub thiab tiv thaiv kev sib cais. (Ua kom tuab) Kev khaws dej kuj yog qhov tseem ceeb tshaj plaws, uas pab tswj cov dej dawb hauv cov mortar, yog li tom qab cov mortar raug tsim, cov khoom siv cementitious muaj sijhawm ntau dua los hydrate. (Kev khaws dej) Nws muaj cov khoom siv cua-entraining, uas tuaj yeem qhia cov npuas cua zoo sib xws thiab zoo los txhim kho kev tsim kho ntawm mortar.
Qhov siab dua qhov viscosity ntawm hydroxypropyl methylcellulose ether, qhov zoo dua qhov kev ua tau zoo ntawm kev khaws dej. Rau tib yam khoom, cov txiaj ntsig viscosity ntsuas los ntawm ntau txoj kev sib txawv yog txawv heev, thiab qee qhov txawm tias muaj ob npaug ntawm qhov sib txawv. Yog li ntawd, thaum piv viscosity, nws yuav tsum tau ua tiav ntawm tib txoj kev sim, suav nrog qhov kub thiab txias, rotor, thiab lwm yam.
Hais txog qhov loj ntawm cov khoom me me, cov khoom me me dua, qhov zoo dua qhov khaws dej. Tom qab cov khoom loj ntawm cellulose ether kov dej, qhov chaw tam sim ntawd yaj thiab tsim cov gel los qhwv cov khoom kom tiv thaiv cov dej molecules los ntawm kev txuas ntxiv mus rau hauv. Qee zaum nws tsis tuaj yeem tawg thiab yaj txawm tias tom qab do ntev, tsim cov kua flocculent lossis agglomeration. Nws cuam tshuam loj heev rau kev khaws dej ntawm cellulose ether, thiab solubility yog ib qho ntawm cov yam tseem ceeb rau kev xaiv cellulose ether. Fineness kuj yog ib qho tseem ceeb ntawm kev ua tau zoo ntawm methyl cellulose ether. MC siv rau cov hmoov qhuav mortar yuav tsum yog hmoov, nrog cov dej tsawg, thiab fineness kuj xav tau 20% -60% ntawm qhov loj me ntawm cov khoom me me kom tsawg dua 63um. Fineness cuam tshuam rau solubility ntawm hydroxypropyl methylcellulose ether. Coarse MC feem ntau yog granular, thiab nws yooj yim yaj hauv dej yam tsis muaj agglomeration, tab sis tus nqi yaj qeeb heev, yog li nws tsis haum rau siv hauv cov hmoov qhuav mortar. Hauv cov hmoov av qhuav, MC raug faib rau ntawm cov khoom siv cementing xws li cov pob zeb sib xyaw, cov khoom siv filler zoo thiab cement, thiab tsuas yog cov hmoov zoo txaus thiaj li zam tau methyl cellulose ether agglomeration thaum sib tov nrog dej.
Feem ntau hais lus, qhov siab dua qhov viscosity, qhov zoo dua qhov dej khaws cia nyhuv. Txawm li cas los xij, qhov siab dua qhov viscosity thiab qhov siab dua qhov hnyav molecular ntawm MC, qhov txo qis hauv nws cov solubility yuav muaj qhov cuam tshuam tsis zoo rau lub zog thiab kev tsim kho ntawm cov mortar. Qhov siab dua qhov viscosity, qhov ntau dua qhov thickening effect ntawm cov mortar, tab sis nws tsis yog proportional ncaj qha. Qhov siab dua qhov viscosity, qhov ntau dua viscosity cov ntub mortar yuav yog, uas yog, thaum lub sijhawm tsim kho, nws yog manifested li lo rau ntawm scraper thiab siab adhesion rau lub substrate. Tab sis nws tsis pab kom nce lub zog ntawm cov ntub mortar nws tus kheej. Qhov ntawd yog, thaum lub sijhawm tsim kho, qhov kev ua tau zoo tiv thaiv-sag tsis pom tseeb. Ntawm qhov tsis sib xws, qee qhov nruab nrab thiab qis viscosity tab sis hloov kho methyl cellulose ethers muaj kev ua tau zoo heev hauv kev txhim kho lub zog ntawm cov ntub mortar.
Qhov kev khaws dej ntawm HPMC kuj muaj feem cuam tshuam nrog qhov kub thiab txias siv, thiab qhov kev khaws dej ntawm methyl cellulose ether txo qis nrog rau qhov kub thiab txias nce ntxiv. Txawm li cas los xij, hauv kev siv cov khoom siv tiag tiag, cov hmoov qhuav mortar feem ntau siv rau cov substrates kub ntawm qhov kub siab (siab dua 40 degrees) hauv ntau qhov chaw, xws li kev pleev xim ntawm phab ntsa sab nraud putty hauv qab lub hnub thaum lub caij ntuj sov, uas feem ntau ua kom nrawm dua Curing ntawm cement thiab hardening ntawm cov hmoov qhuav mortar. Qhov kev poob qis ntawm qhov kev khaws dej ua rau muaj kev xav tias ob qho tib si workability thiab tawg tsis kam raug cuam tshuam, thiab nws yog qhov tseem ceeb tshwj xeeb kom txo qhov cuam tshuam ntawm cov yam ntxwv kub hauv qab no. Hauv qhov no, methyl hydroxyethyl cellulose ether additives tam sim no suav hais tias yog nyob rau pem hauv ntej ntawm kev txhim kho thev naus laus zis. Txawm hais tias qhov ntau ntawm methyl hydroxyethyl cellulose nce ntxiv (lub caij ntuj sov mis), qhov kev ua haujlwm thiab tawg tsis kam tseem tsis tuaj yeem ua tau raws li qhov xav tau ntawm kev siv. Los ntawm qee qhov kev kho tshwj xeeb ntawm MC, xws li kev nce qib ntawm etherification, thiab lwm yam, cov dej khaws cov nyhuv tuaj yeem tswj tau ntawm qhov kub siab dua, yog li nws tuaj yeem muab kev ua tau zoo dua hauv qab cov xwm txheej hnyav.
Feem ntau, HPMC muaj qhov kub gel, uas tuaj yeem faib ua 60 hom, 65 hom, thiab 75 hom. Rau cov lag luam uas siv xuab zeb dej rau cov mortar sib xyaw ua ke, nws yog qhov zoo tshaj plaws los siv 75-hom HPMC nrog qhov kub gel siab. Cov koob tshuaj ntawm HPMC yuav tsum tsis txhob siab dhau, txwv tsis pub nws yuav ua rau cov dej ntawm cov mortar xav tau ntau ntxiv, nws yuav lo rau ntawm lub trowel, thiab lub sijhawm teeb tsa yuav ntev dhau, uas yuav cuam tshuam rau kev tsim kho. Cov khoom mortar sib txawv siv HPMC nrog cov viscosities sib txawv, thiab tsis txhob siv HPMC viscosity siab. Yog li ntawd, txawm hais tias cov khoom hydroxypropyl methylcellulose zoo, lawv tau txais kev qhuas thaum lawv siv zoo. Kev xaiv HPMC zoo yog lub luag haujlwm tseem ceeb ntawm cov neeg ua haujlwm hauv chaw kuaj mob hauv tuam txhab.
Lub sijhawm tshaj tawm: Plaub Hlis-12-2023