Hydroxypropyl methylcellulose (HPMC) yog cov khoom siv polymer feem ntau siv hauv cov khoom siv hauv tsev, tshwj xeeb tshaj yog nyob rau hauv gypsum ntsib plaster, qhov chaw nws ua lub luag haujlwm tseem ceeb. Raws li ib qho ntxiv, HPMC tuaj yeem txhim kho kev ua haujlwm zoo, tuav dej thiab ua kom zoo ntawm gypsum ntsib plaster, yog li nws tau siv dav hauv kev tsim kho thiab kho kom zoo nkauj.
1. Cov yam ntxwv tseem ceeb ntawm HPMC
HPMC yog non-ionic cellulose ether nrog dej solubility zoo thiab thickening zog. Nws tuaj yeem yaj sai sai hauv dej los tsim cov kua colloidal tsis sib xws, thiab muaj qhov adhesion zoo, lubricity, film-forming thiab dej tuav. Cov yam ntxwv no ua rau HPMC dav siv hauv cov khoom siv hauv tsev, tshwj xeeb tshaj yog tsim rau siv hauv cov ntaub ntawv gypsum.
Cov yam ntxwv tseem ceeb ntawm HPMC suav nrog cov hauv qab no:
Kev tuav dej: HPMC tuaj yeem khaws cov dej noo hauv gypsum ntsib plaster, yog li ncua sijhawm qhib thiab sijhawm ua haujlwm ntawm cov khoom.
Thickening: Raws li cov thickener, HPMC tuaj yeem ua kom cov viscosity ntawm plaster, tiv thaiv sagging, thiab txhim kho kev txhuam.
Lubricity: Lub lubricating zog ntawm HPMC txhim kho kev tuav ntawm plaster thiab ua kom kev tsim kho yooj yim dua.
Cov cuab yeej ua yeeb yaj kiab: Nws tuaj yeem tsim cov yeeb yaj kiab tiv thaiv ntawm qhov chaw ntawm plaster, txhim kho qhov tawg tsis kam ntawm plaster.
2. Mechanism ntawm kev txiav txim ntawm HPMC nyob rau hauv gypsum ntsib plaster
Tom qab ntxiv HPMC rau gypsum ntsib plaster, cov khoom siv tau zoo dua qub hauv cov hauv qab no:
Txhim kho dej tuav: Thaum lub sij hawm kev tsim kho ntawm gypsum ntsib plaster, yog hais tias cov dej poob sai heev, nws yuav ua rau tsis sib xws hardening, tawg thiab txo lub zog. HPMC tuaj yeem tsim cov yeeb yaj kiab zoo hauv cov plaster, ua kom cov dej ntws qeeb qeeb, yog li cov plaster tuaj yeem tuav cov dej txaus thaum lub sijhawm ziab, ua kom nws cov tawv tawv tsis sib xws, yog li zam kev tsim cov kab nrib pleb.
Txhim kho adhesion: HPMC tuaj yeem tsim ib zaj duab xis nyias ntawm plaster, uas tuaj yeem txhim kho qhov adhesion thaum sib cuag nrog lub substrate, kom cov adhesion ntawm plaster ntawm phab ntsa yog nce. Tshwj xeeb tshaj yog nyob rau hauv qhov ntxeem tau thiab qhuav substrates, cov dej tuav cov nyhuv ntawm HPMC kuj tuaj yeem tiv thaiv cov substrate los ntawm absorbing dej sai heev, yog li txhim kho cov txiaj ntsig kev sib raug zoo.
Txhim khu kev tiv thaiv kab mob: Gypsum ntsib plaster yog qhov cuam tshuam rau cov kab nrib pleb vim qhov hloov pauv ntawm qhov kub thiab txias.HPMC slows down lub qhuav shrinkage tus nqi los ntawm kev kho cov evaporation tus nqi ntawm cov dej, yog li zoo txo qhov kev pheej hmoo ntawm tawg nyob rau hauv lub plaster txheej. Nyob rau tib lub sijhawm, cov yeeb yaj kiab colloid tsim los ntawm HPMC tuaj yeem muab qee yam kev tiv thaiv kev tiv thaiv rau cov plaster.
Txhim kho kev ua haujlwm: HPMC tuaj yeem ua kom cov viscosity thiab plasticity ntawm plaster, ua kom yooj yim rau kev khiav lag luam thaum txhuam thiab qib. HPMC txhim kho kev ua haujlwm ntawm plaster, thiab cov neeg ua haujlwm tsim kho tuaj yeem tswj tau qhov tuab thiab tiaj tus, uas yuav pab kom tau txais cov txiaj ntsig zoo dua.
3. HPMC txhim kho kev ua haujlwm ntawm gypsum ntsib plaster
Qhov sib ntxiv ntawm HPMC muaj ntau yam kev txhim kho ntawm kev ua haujlwm ntawm gypsum ntsib plaster, suav nrog:
Kev txhim kho Rheological: HPMC tuaj yeem ua kom cov viscosity ntawm plaster, tswj lub fluidity ntawm plaster, tiv thaiv sagging teeb meem, thiab txhim kho kev txhuam hniav ntawm plaster.
Txhim khu kev tiv thaiv Frost: Cov zaj duab xis colloid tsim los ntawm HPMC muaj kev tiv thaiv ntawm plaster rau ib qho twg, tiv thaiv lub plaster los ntawm khov thiab tawg nyob rau hauv qhov kub thiab txias ib puag ncig, thiab txhim kho cov khoom tiv thaiv Frost.
Txhim kho shrinkage kuj:HPMC tsub kom cov dej noo nyob rau hauv plaster, alleviates lub shrinkage teeb meem tshwm sim los ntawm dej evaporation, thiab ua rau lub plaster txheej ruaj khov thiab tsis tshua muaj kev tawg.
Txhim kho adhesion: Cov khoom sib txuas ntawm HPMC tuaj yeem txhim kho qhov adhesion ntawm plaster rau saum npoo ntawm substrate, ua rau cov txheej tsis tshua muaj kev poob.
4. Kev ceev faj hauv kev siv HPMC
Txawm hais tias HPMC muaj ntau qhov zoo rau gypsum ntsib plaster, cov nram qab no yuav tsum tau sau tseg hauv nws txoj kev siv:
Kev tswj tus nqi ntxiv: HPMC ntau dhau lawm yuav ua rau cov plaster nplaum dhau, ua rau nws nyuaj rau du, cuam tshuam rau kev tsim kho. Feem ntau hais lus, qhov sib ntxiv ntawm HPMC yuav tsum tau tswj nyob rau hauv thaj tsam ntawm 0.1% -0.5%, thiab kho raws li qhov xav tau tiag tiag.
Txawm sib tov:HPMC yuav tsum tau ua kom tag nrho stirred thaum tov nrog cov ntaub ntawv xws li gypsum kom ntseeg tau tias cov dispersion thiab uniform kev ua tau zoo. HPMC tuaj yeem yaj hauv dej ua ntej, tom qab ntawd ntxiv rau gypsum rau kev sib xyaw, lossis nws tuaj yeem sib xyaw sib npaug ntawm cov hmoov qhuav.
Compatibility nrog rau lwm yam additives: Nyob rau hauv gypsum ntsib plaster, HPMC feem ntau yog siv nrog rau lwm yam additives, xws li dej reducers, dej retainers, thiab lwm yam. Thaum ntxiv ntau yam additives, xyuam xim rau lawv compatibility kom tsis txhob muaj kev cuam tshuam cov kev ua tau zoo.
5. Qhov tseem ceeb ntawm HPMC hauv kev lag luam
Hauv gypsum ntsib plaster thiab lwm yam khoom siv hauv tsev, HPMC, ua ib qho tseem ceeb ntxiv, ua lub luag haujlwm tseem ceeb hauv kev txhim kho cov khoom siv vim nws cov dej tuav tau zoo, adhesion, thickening thiab tawg tsis kam. Nyob rau hauv xyoo tas los no, nrog kev xav tau ntau ntxiv rau cov khoom siv vaj tsev ntsuab, kev tiv thaiv ib puag ncig ntawm HPMC kuj tau ua rau nws maj mam nyiam los ntawm kev ua lag luam. Hauv cov tsev niaj hnub no, HPMC tsis tsuas yog txhim kho kev siv cov gypsum ntsib plaster, tab sis kuj txhim kho kev tsim kho kom zoo thiab ua haujlwm zoo, thiab txhawb kev tsim kho tshiab ntawm kev tsim kho tshuab.
Daim ntawv thov ntawm HPMC hauv gypsum ntsib plaster tsis tsuas yog txhim kho cov dej tuav, adhesion thiab tawg tsis kam ntawm cov khoom, tab sis kuj txhim kho kev tsim kho kev ua tau zoo, ua rau nws yog ib qho tseem ceeb ntxiv hauv kev tsim kho. HPMC cov yam ntxwv tshwj xeeb thiab kev txhim kho ntau yam kev ua tau zoo tau ua rau nws tseem ceeb hauv cov khoom siv hauv tsev, muab kev txhawb zog rau kev ua haujlwm zoo, ua haujlwm ruaj khov. Nyob rau yav tom ntej, nrog kev txhim kho txuas ntxiv ntawm kev tsim kho thev naus laus zis, daim ntawv thov kev cia siab ntawm HPMC hauv cov khoom siv gypsum yuav dav dua.
Post lub sij hawm: Nov-19-2024