Cov tshuaj ntxiv ua lub luag haujlwm tseem ceeb hauv kev txhim kho kev ua tau zoo ntawm kev tsim cov mortar qhuav. Cov hauv qab no tshuaj xyuas thiab piv cov khoom tseem ceeb ntawm cov hmoov latex thiab cellulose, thiab tshuaj xyuas kev ua tau zoo ntawm cov khoom mortar qhuav siv cov tshuaj ntxiv.
Cov hmoov latex uas yaj tau dua tshiab
Cov hmoov latex uas yaj tau dua tshiabCov hmoov latex qhuav yog ua los ntawm kev txau kom qhuav ntawm cov polymer emulsion tshwj xeeb. Cov hmoov latex qhuav yog qee cov khoom me me ntawm 80 ~ 100 hli sib sau ua ke. Cov khoom me me no yaj tau hauv dej thiab tsim cov khoom sib xyaw ruaj khov me ntsis loj dua li cov khoom me me emulsion qub, uas tsim cov zaj duab xis tom qab ziab thiab ziab.
Cov kev hloov kho sib txawv ua rau cov hmoov latex uas rov tawg tau muaj cov yam ntxwv sib txawv xws li tiv taus dej, tiv taus alkali, tiv taus huab cua thiab yooj ywm. Cov hmoov latex siv rau hauv cov mortar tuaj yeem txhim kho qhov tiv taus kev cuam tshuam, kev ruaj khov, kev hnav tsis kam, yooj yim ntawm kev tsim kho, lub zog sib txuas thiab kev sib koom ua ke, tiv taus huab cua, tiv taus khov-thaw, tiv taus dej, lub zog khoov thiab lub zog khoov ntawm cov mortar.
Cellulose ether
Cellulose ether yog ib lo lus dav dav rau cov khoom tsim los ntawm cov tshuaj tiv thaiv ntawm alkali cellulose thiab etherifying agent nyob rau hauv qee qhov xwm txheej. Alkali cellulose raug hloov los ntawm cov neeg sawv cev etherifying sib txawv kom tau txais cov cellulose ethers sib txawv. Raws li cov khoom ionization ntawm cov substituents, cellulose ethers tuaj yeem muab faib ua ob pawg: ionic (xws li carboxymethyl cellulose) thiab non-ionic (xws li methyl cellulose). Raws li hom substituent, cellulose ether tuaj yeem muab faib ua monoether (xws li methyl cellulose) thiab sib xyaw ether (xws li hydroxypropyl methyl cellulose). Raws li kev yaj sib txawv, nws tuaj yeem muab faib ua dej-soluble (xws li hydroxyethyl cellulose) thiab organic solvent-soluble (xws li ethyl cellulose), thiab lwm yam. Cov mortar qhuav-mixed yog feem ntau dej-soluble cellulose, thiab dej-soluble cellulose yog muab faib ua hom instant thiab nto kho qeeb hom yaj.
Lub mechanism ntawm kev ua haujlwm ntawm cellulose ether hauv mortar yog raws li nram no:
(1) Tom qab lubcellulose etherHauv cov mortar yog yaj rau hauv dej, qhov kev faib tawm zoo thiab sib xws ntawm cov khoom siv cementitious hauv lub kaw lus tau ua kom ntseeg tau vim yog qhov kev ua haujlwm ntawm qhov chaw, thiab cellulose ether, ua ib qho colloid tiv thaiv, "qhwv" cov khoom khov thiab Ib txheej ntawm cov zaj duab xis lubricating yog tsim rau ntawm nws qhov chaw sab nraud, uas ua rau lub kaw lus mortar ruaj khov dua, thiab tseem txhim kho qhov fluidity ntawm mortar thaum lub sijhawm sib tov thiab qhov du ntawm kev tsim kho.
(2) Vim nws cov qauv molecular, cov kua cellulose ether ua rau cov dej hauv cov mortar tsis yooj yim poob, thiab maj mam tso nws tawm mus ntev, ua rau cov mortar khaws dej zoo thiab ua haujlwm tau zoo.
ntoo fiber
Cov ntoo fiber yog ua los ntawm cov nroj tsuag ua cov khoom siv tseem ceeb thiab ua tiav los ntawm ntau yam thev naus laus zis, thiab nws cov kev ua tau zoo txawv ntawm cov cellulose ether. Cov yam ntxwv tseem ceeb yog:
(1) Insoluble nyob rau hauv dej thiab cov kuab tshuaj, thiab kuj insoluble nyob rau hauv cov kua qaub tsis muaj zog thiab cov tshuaj tsis muaj zog
(2) Siv rau hauv mortar, nws yuav sib tshooj rau hauv cov qauv peb-seem hauv lub xeev zoo li qub, ua rau thixotropy thiab sag tsis kam ntawm mortar, thiab txhim kho kev tsim kho.
(3) Vim yog cov qauv peb-seem ntawm cov ntoo fiber, nws muaj cov khoom ntawm "dej-locking" hauv cov mortar sib xyaw, thiab cov dej hauv cov mortar yuav tsis yooj yim nqus lossis tshem tawm. Tab sis nws tsis muaj qhov khaws cia dej siab ntawm cellulose ether.
(4) Cov nyhuv capillary zoo ntawm cov ntoo fiber muaj lub luag haujlwm ntawm "kev coj dej" hauv cov mortar, uas ua rau qhov chaw thiab cov dej noo sab hauv ntawm cov mortar zoo li sib xws, yog li txo cov kab nrib pleb los ntawm kev tsis sib xws.
(5) Cov ntoo fiber tuaj yeem txo qhov kev ntxhov siab ntawm cov mortar tawv thiab txo qhov shrinkage thiab tawg ntawm cov mortar.
Lub sijhawm tshaj tawm: Plaub Hlis-25-2024