Hydroxypropyl methylcellulose (HPMC) yog cellulose ether feem ntau siv nyob rau hauv ntau yam lag luam, suav nrog gypsum hauv kev tsim kho kev lag luam. Qhov no multifunctional compound plays lub luag haujlwm tseem ceeb hauv kev txhim kho kev ua haujlwm thiab cov khoom ntawm gypsum plaster.
1. Taw qhia rau HPMC:
Hydroxypropyl methylcellulose yog ib qho hluavtaws derivative ntawm natural polymer cellulose. Nws yog tsim los ntawm kev kho cellulose nrog propylene oxide thiab methyl chloride. Qhov tshwm sim yog cov dej-soluble polymer nrog cov khoom tshwj xeeb uas tuaj yeem pom cov ntawv thov hauv ntau qhov kev lag luam.
2. Kev ua haujlwm ntawm HPMC:
Dej solubility: HPMC yooj yim soluble hauv dej, tsim cov pob tshab thiab tsis muaj xim.
Zaj duab xis-forming zog: Zaj duab xis-forming zog pab tsim ib zaj duab xis tiv thaiv ntawm qhov chaw.
Thermal gelation: HPMC tau txais kev rov qab thermal gelation, uas txhais tau tias nws tuaj yeem tsim cov gel ntawm qhov kub thiab txias thiab rov qab los rau kev daws thaum txias.
Viscosity: Lub viscosity ntawm HPMC cov tshuaj tuaj yeem hloov kho raws li qib kev hloov pauv thiab qhov hnyav molecular.
3. Kev siv HPMC hauv gypsum:
Kev tuav dej: HPMC ua tus neeg saib xyuas dej hauv gypsum, tiv thaiv dej sai sai thaum teeb tsa. Qhov no txhim kho maneuverability thiab muab lub neej siv ntev dua.
Txhim kho Adhesion: Cov yeeb yaj kiab tsim cov khoom ntawm HPMC pab txhim kho stucco adhesion rau ntau yam substrates, tsim kom muaj kev sib raug zoo.
Kev Tswj Xyuas Kom Zoo: Los ntawm kev tswj cov viscosity ntawm cov gypsum sib tov, HPMC pab tswj cov ntawv thov sib xws, ua kom muaj qhov sib xws ntawm qhov chaw tiav.
Crack Resistance: Siv HPMC hauv plaster pab txhim kho kev yooj yim thiab txo qhov yuav ua rau tawg ntawm cov khoom tiav.
Lub Sijhawm Teeb Meem: HPMC tuaj yeem cuam tshuam lub sijhawm teeb tsa ntawm gypsum yog li nws tuaj yeem hloov kho kom tau raws li cov ntawv thov tshwj xeeb.
4. Dosage thiab mixing:
Tus nqi ntawm HPMC siv hauv gypsum yog nyob ntawm ntau yam xws li cov khoom xav tau, kev tsim gypsum thiab cov ntawv thov. Feem ntau, nws yog ntxiv rau qhuav mix thaum lub sij hawm sib tov. Cov txheej txheem sib xyaw yog qhov tseem ceeb los xyuas kom meej qhov sib txawv ntawm qhov sib txawv thiab kev ua haujlwm zoo.
5.Compatibility thiab kev ruaj ntseg:
HPMC yog sib xws nrog ntau yam ntawm lwm yam additives siv nyob rau hauv plaster formulations. Tsis tas li ntawd, nws raug suav hais tias muaj kev nyab xeeb rau kev siv hauv cov khoom siv hauv tsev thiab ua raws li cov qauv kev cai.
6. Xaus:
Hydroxypropyl methylcellulose (HPMC) plays lub luag haujlwm tseem ceeb hauv kev txhim kho kev ua haujlwm ntawm gypsum plaster. Nws cov khoom tshwj xeeb pab txhim kho kev ua haujlwm, adhesion thiab tag nrho zoo ntawm plaster. Ib qho khoom siv dav siv hauv kev tsim kho kev lag luam, HPMC tseem yog ib qho tseem ceeb ntawm cov txheej txheem plaster zoo.
Post lub sij hawm: Jan-19-2024