Cov plaster gypsum uas sib dua yog cov khoom siv hauv tsev uas tsis ua rau ib puag ncig puas tsuaj uas siv dav hauv kev kho kom zoo nkauj phab ntsa sab hauv, cov khoom siv rwb thaiv tsev thiab kev kho kom zoo nkauj. Nws yog ua los ntawm cov gypsum ua cov khoom siv cementing tseem ceeb, ntxiv nrog cov pob zeb sib xyaw ua ke (xws li perlite, vitrified microspheres, ua npuas dej, thiab lwm yam). Vim yog cov yam ntxwv ntawm gypsum nws tus kheej, xws li kev coagulation sai thiab kev ua kom tawv, kev ntswj loj, thiab kev sib tsoo yooj yim, txhawm rau txhim kho nws txoj kev ua haujlwm thiab kev siv zoo, feem ntau nws yuav tsum ntxiv ntau yam khoom ntxiv los txhim kho nws txoj kev ua haujlwm. Ntawm lawv,Hydroxypropyl methylcellulose (HPMC), ua ib qho tseem ceeb cellulose ether ua haujlwm, ua lub luag haujlwm tseem ceeb hauv cov plaster gypsum uas tsis hnyav.
1. Cov khoom tseem ceeb ntawm HPMC
HPMC yog ib qho polymer uas tsis yog ionic uas yaj tau hauv dej los ntawm kev hloov kho etherification ntawm cov cellulose molecular ntuj. Nws muaj cov yam ntxwv zoo xws li khaws dej, ua kom tuab, ua kom lubricity, ua zaj duab xis thiab ua kom ncua. Nws feem ntau ntxiv rau hauv daim ntawv ntawm hmoov rau hauv plaster, mortar thiab lwm yam khoom siv hauv tsev qhuav, thiab nws o thiab yaj sai sai thaum nws kov dej ua lub luag haujlwm tseem ceeb.
2. Lub luag haujlwm tseem ceeb ntawm HPMC hauv cov plaster gypsum uas sib dua
2.1. Txhim kho kev khaws dej thiab ua kom lub sijhawm ua haujlwm ntev dua
Gypsum muaj lub sijhawm pib teeb tsa luv luv thiab nqus dej tau zoo, thiab nws yooj yim poob dej sai thaum lub sijhawm tsim kho, ua rau muaj teeb meem xws li tawg thiab hmoov. HPMC muaj kev khaws dej zoo heev thiab tuaj yeem tsim cov dej sib xws hauv cov slurry, txo qhov nkag mus ntawm cov dej dawb rau hauv cov substrate, thiab ncua cov dej evaporation, yog li:
Xyuas kom meej tias cov tshuaj tiv thaiv hydration tag nrho ntawm gypsum thiab txhim kho lub zog ntawm cov khoom siv;
Txo cov kab nrib pleb thiab txhim kho qhov zoo ntawm qhov pom tseeb;
Ntev lub sijhawm ua haujlwm ntawm kev tsim kho, txhim kho kev ua haujlwm zoo thiab kev hloov pauv ntawm kev tsim kho, tshwj xeeb tshaj yog nyob rau hauv qhov kub thiab txias thiab qhuav.
2.2. Txhim kho kev tsim kho thiab kev ua haujlwm tau zoo
HPMC tuaj yeem txhim kho qhov sib xws thiab qhov ceev ntawm gypsum plaster, ua rau nws cov slurry du thiab ntau dua kua. Tshwj xeeb pom tseeb hauv:
Yooj yim rau do thiab thov, yooj yim thov;
Txo cov khoom slippage thiab hmoov;
Xyuas kom meej tias qhov sib npaug ntawm cov plaster ntawm phab ntsa thiab txhim kho qhov chaw tiaj tus.
2.3. Txhim kho qhov kev nplaum thiab cov yam ntxwv tiv thaiv kev sagging
HPMC tuaj yeem tsim cov zaj duab xis adsorption zoo ntawm cov slurry thiab cov substrate, txhim kho qhov adhesion ntawm plaster thiab phab ntsa nto, thiab yog li ua tau zoo:
Txo cov teeb meem hollowing thiab poob;
Txhim kho lub peev xwm tiv thaiv kev sagging hauv kev tsim kho ntsug, ua rau cov khoom siv tsis tshua muaj peev xwm swb, uas yog qhov zoo rau kev tsim cov txheej tuab;
Pab tsim ib txheej tiav du thiab ntom.
2.4. Kho qhov sib xws thiab qhov tuab ntawm cov khoom
HPMC muaj peev xwm tswj tau qhov viscosity ntawm cov tshuaj. Tom qab yaj hauv dej, nws tsim cov viscoelastic colloid system, uas ua rau tag nrho cov gypsum slurry ruaj khov, tiv thaiv kev faib ua pawg thiab kev sib cais, thiab txhim kho qhov ntim ntawm cov khoom siv. Tib lub sijhawm, raws li qib viscosity thiab qhov ntxiv ntawm ntau hom HPMC, cov neeg siv tuaj yeem hloov kho qhov sib xws ntawm cov plaster kom haum rau ntau txoj kev tsim kho (xws li kev pleev tes thiab kev txau tshuab).
2.5. Txhim kho qhov tsis kam tawg tom qab kev tsim kho
Cov plaster gypsum uas ua los ntawm cov khoom sib xyaw ua ke yooj yim ua rau cov kab nrib pleb me me vim nws cov khoom sib xyaw me me thiab cov kab nrib pleb me me. HPMC tuaj yeem txo qhov kev ntxhov siab thiab cov kab nrib pleb los ntawm kev txhim kho kev khaws dej, kev teeb tsa qeeb thiab kev ywj pheej. Tsis tas li ntawd, HPMC kuj tseem tuaj yeem txhim kho qhov kev tiv thaiv kev hloov pauv ntawm cov plaster, ua rau nws tsim nyog dua rau ntau qhov chaw sib txawv.
3. Cov kev ceev faj rau kev siv HPMC
Txoj kev ntxiv: HPMC feem ntau yog sib xyaw nrog lwm cov hmoov ua cov khoom sib xyaw qhuav ua ntej. Nws tsis pom zoo kom ntxiv nws ncaj qha rau hauv dej thiab do nws kom tsis txhob muaj kev sib sau ua ke.
Kev Tswj Xyuas Kev Siv Tshuaj: Kev ntxiv ntau dhau yuav ua rau lub sijhawm ua kom khov ntau dhau, txo lub zog, thiab txo qhov lo. Feem ntau cov tshuaj ntxiv yog 0.1% ~ 0.5%.
Kev xaiv qauv: HPMC nrog cov viscosities sib txawv thiab cov qib hloov pauv yuav tsum tau xaiv raws li kev tsim khoom kom coj mus rau hauv tus account ob qho tib si kev ua tau zoo ntawm kev tsim kho thiab kev ua tiav ntawm cov khoom tiav.
4. Qhov tseem ceeb ntawm HPMC hauv kev txhawb nqa cov ntaub ntawv tsim vaj tsev ntsuab
Raws li qhov kev hloov pauv tam sim no ntawm kev tawm tswv yim rau kev txuag hluav taws xob thiab kev tsim kho uas zoo rau ib puag ncig, cov plaster gypsum uas sib dua thiab sib dua tau siv ntau dua hauv cov tsev ntsuab vim nws qhov zoo ntawm cov peev txheej rov ua dua tshiab, cov pa roj carbon tsawg, thiab kev nplij siab zoo. HPMC, ua cov khoom siv ntxiv uas tsis tseem ceeb hauv cov mis ntawm gypsum plaster, tsis yog tsuas yog txhim kho nws cov kev ua tau zoo xwb, tab sis kuj txhim kho nws cov kev ua haujlwm zoo thiab kev siv cov khoom siv, txo cov khoom pov tseg los ntawm kev ua haujlwm dua tshiab, thiab yog qhov tseem ceeb los txhawb kev txhim kho cov khoom siv tsev ntsuab.
Hydroxypropyl methylcellulose (HPMC) ua ntau lub luag haujlwm hauv cov plaster gypsum uas sib dua, suav nrog kev khaws dej, ua kom tuab, ua kom lubrication, tiv thaiv kev sagging thiab kev sib txuas zoo dua, uas ua rau kev ua haujlwm tau zoo dua, cov khoom siv kho tshuab thiab lub neej ua haujlwm ntawm gypsum plaster. Nrog rau qhov kev thov ntau ntxiv rau cov khoom siv sib dua, txuag hluav taws xob thiab cov khoom siv ib puag ncig hauv kev lag luam kev tsim kho, qhov tseem ceeb ntawm HPMC hauv cov kab ke gypsum-based yuav dhau los ua qhov tseem ceeb dua, thiab nws tus nqi kev siv tshuab thiab qhov chaw thov kev lag luam yuav txuas ntxiv nthuav dav. Kev xaiv thiab siv HPMC kom raug yuav muab lub hauv paus ruaj khov rau kev txhim kho kev ua haujlwm ntawm gypsum plaster systems thiab xyuas kom meej qhov zoo ntawm cov haujlwm tsim kho.
Lub sijhawm tshaj tawm: Lub Xya Hli-03-2025