Ua ib yam khoom siv hauv kev tsim kho uas siv dav hauv kev lag luam kev tsim kho, cov tshuaj mortar ua lub luag haujlwm tseem ceeb hauv kev tsim kho thiab kev ua haujlwm. Qhov dej ntws ntawm cov tshuaj mortar yog ib qho ntawm cov cim tseem ceeb uas cuam tshuam rau nws txoj kev ua haujlwm tsim kho. Qhov dej ntws zoo pab txhawb rau kev yooj yim ntawm kev ua haujlwm tsim kho thiab qhov zoo ntawm lub tsev. Txhawm rau txhim kho qhov dej ntws thiab kev ua haujlwm ntawm cov tshuaj mortar, ntau yam khoom ntxiv feem ntau siv rau kev hloov kho. Ntawm lawv,Hydroxypropyl methylcellulose (HPMC), raws li cov tshuaj polymer uas feem ntau siv hauv dej, ua lub luag haujlwm tseem ceeb hauv cov mortar. .
Cov yam ntxwv tseem ceeb ntawm HPMC: HPMC yog cov khoom siv polymer uas yaj tau hauv dej ua los ntawm cov cellulose ntuj uas tau hloov kho los ntawm tshuaj lom neeg. Nws muaj cov khoom zoo heev uas ua rau tuab, gelling, khaws dej thiab lwm yam khoom. Nws tsis yaj hauv dej, tab sis tuaj yeem tsim cov kua nplaum hauv dej, yog li nws feem ntau siv dav hauv kev tsim kho, txheej, tshuaj thiab lwm yam teb. Thaum siv ua cov khoom ntxiv rau cov tshuaj pleev, HPMC tuaj yeem txhim kho qhov ua tau zoo ntawm cov tshuaj pleev, khaws dej thiab ua haujlwm tau zoo.
Lub mechanism ntawm HPMC rau mortar fluidity:
Cov nyhuv ua kom tuab: HPMC nws tus kheej muaj cov nyhuv ua kom tuab. Thaum ntxiv rau hauv cov tshuaj khib, nws tuaj yeem ua rau kom cov viscosity ntawm cov tshuaj khib nce ntxiv. Cov nyhuv ua kom tuab yog vim cov HPMC molecules tsim cov qauv network hauv dej, uas nqus dej thiab nthuav dav, ua rau cov viscosity ntawm cov dej theem nce ntxiv. Cov txheej txheem no tso cai rau kev hloov kho cov kua ntawm cov tshuaj khib. Thaum cov ntsiab lus HPMC hauv cov tshuaj khib siab, cov dej ntws dawb yuav raug txwv rau qee qhov, yog li qhov kua tag nrho ntawm cov tshuaj khib yuav qhia qee qhov kev hloov pauv.
Txhim kho kev khaws dej: HPMC tuaj yeem tsim ib daim nyias nyias hauv cov mortar kom txo cov dej evaporation thiab txhim kho kev khaws dej ntawm cov mortar. Cov mortar uas khaws dej zoo dua tuaj yeem ua haujlwm tau ntev dua, uas yog qhov tseem ceeb rau kev yooj yim ntawm kev tsim kho thaum lub sijhawm tsim kho. Kev khaws dej ntau tuaj yeem tiv thaiv cov mortar kom tsis txhob qhuav ua ntej thiab txhim kho lub sijhawm tsim kho thiab kev ua haujlwm ntawm cov mortar.
Kev tawg: HPMC tuaj yeem tsim cov tshuaj colloidal hauv dej, uas tuaj yeem txhim kho kev tawg ntawm cov khoom siv mortar. Qhov fluidity ntawm mortar tsis yog tsuas yog cuam tshuam nrog qhov sib piv ntawm cement, xuab zeb thiab admixtures, tab sis kuj cuam tshuam nrog kev tawg ntawm cov khoom no. Los ntawm kev kho qhov ntau ntawm HPMC, cov khoom hauv mortar tuaj yeem tawg ntau dua, yog li txhim kho qhov fluidity ntxiv.
Cov nyhuv gelling: HPMC tuaj yeem txhawb kev faib cov khoom me me hauv cov mortar thiab txhim kho kev ruaj khov ntawm nws cov qauv. Los ntawm kev txhim kho cov nyhuv gelling, HPMC tuaj yeem tswj tau qhov ruaj khov ntawm cov mortar thaum lub sijhawm khaws cia ntev thiab zam kev txo qis ntawm cov kua vim yog lub sijhawm qeeb.
Cov nyhuv txhim kho kev yas: Kev ntxiv HPMC kuj tseem tuaj yeem txhim kho qhov yas ntawm cov mortar, ua rau nws yooj yim dua rau kev ua haujlwm thiab muaj kev yas zoo dua thaum lub sijhawm tsim kho. Piv txwv li, thaum plastering phab ntsa, kev ua kom zoo thiab kev yas tuaj yeem txo qhov tshwm sim ntawm cov kab nrib pleb thiab txhim kho qhov zoo ntawm plastering.
Kev siv HPMC zoo tshaj plaws hauv kev kho qhov fluidity ntawm mortar:
Kev tswj cov tshuaj: Qhov ntau npaum li cas ntawm HPMC cuam tshuam ncaj qha rau qhov fluidity ntawm mortar. Feem ntau hais lus, thaum ntxiv HPMC yog qhov nruab nrab, qhov fluidity thiab dej khaws cia ntawm mortar tuaj yeem txhim kho tau zoo heev. Txawm li cas los xij, HPMC ntau dhau yuav ua rau qhov viscosity ntawm mortar siab dhau, uas ua rau nws txo qis nws cov fluidity. Yog li ntawd, qhov ntau npaum li cas ntawm HPMC ntxiv yuav tsum tau tswj kom raug raws li qhov xav tau tshwj xeeb hauv daim ntawv thov.
Kev sib koom tes nrog lwm cov admixtures: Ntxiv rau HPMC, lwm cov admixtures feem ntau ntxiv rau hauv mortar, xws li superplasticizers, retarders, thiab lwm yam. Kev sib koom tes ntawm cov admixtures no thiab HPMC tuaj yeem tswj tau qhov ntws ntawm mortar zoo dua. Piv txwv li, superplasticizers tuaj yeem txo cov dej hauv mortar thiab txhim kho qhov fluidity ntawm mortar, thaum HPMC tuaj yeem txhim kho nws cov dej khaws cia thiab kev ua haujlwm tsim kho thaum tswj hwm qhov viscosity ntawm mortar.
Kev kho kom haum rau ntau hom mortar sib txawv: Ntau hom mortar muaj cov kev xav tau sib txawv ntawm kev ua kua. Piv txwv li, plastering mortar muaj cov kev xav tau ntau dua ntawm kev ua kua, thaum masonry mortar them sai dua rau nws txoj kev sib txuas thiab tuab. Thaum lub sijhawm no, qhov ntau thiab hom HPMC ntxiv yuav tsum tau ua kom zoo thiab kho raws li qhov xav tau ntawm ntau hom mortars kom ntseeg tau tias muaj kev ua kua zoo tshaj plaws thiab sib npaug.
Raws li cov khoom siv mortar feem ntau siv,HPMCtuaj yeem kho qhov fluidity ntawm mortar los ntawm kev ua kom tuab, khaws dej, dispersion, gelling, thiab lwm yam. Nws cov yam ntxwv tshwj xeeb ua rau cov mortar ua haujlwm tau zoo dua thiab ruaj khov thaum lub sijhawm tsim kho. Txawm li cas los xij, qhov ntau npaum li cas ntawm HPMC yuav tsum tau kho kom raug raws li cov xwm txheej tshwj xeeb ntawm daim ntawv thov kom tsis txhob siv ntau dhau uas ua rau txo qis fluidity. Nrog rau kev txhim kho tas mus li ntawm cov kev xav tau ntawm cov mortar hauv kev lag luam kev tsim kho, cov nyhuv tswj hwm ntawm HPMC muaj kev cia siab dav dav rau yav tom ntej.
Lub sijhawm tshaj tawm: Lub Ib Hlis-10-2025