Kev tsim kho tshiab ntawm HEMC cellulose ethers los txo cov agglomeration hauv gypsum-based tshuab-txhaj plasters

Kev tsim kho tshiab ntawm HEMC cellulose ethers los txo cov agglomeration hauv gypsum-based tshuab-txhaj plasters

Gypsum-based machine-sprayed plaster (GSP) tau siv dav hauv Western Europe txij li xyoo 1970s. Qhov tshwm sim ntawm cov tshuab txau tau ua kom zoo dua qub ntawm kev siv plastering thaum txo cov nqi tsim kho. Nrog rau qhov tob ntawm GSP kev lag luam, dej-soluble cellulose ether tau dhau los ua ib qho tseem ceeb ntxiv. Cellulose ether endows GSP nrog cov dej tuav tau zoo, uas txwv tsis pub cov substrate nqus dej noo hauv plaster, yog li tau txais lub sijhawm ruaj khov thiab cov khoom siv zoo. Tsis tas li ntawd, qhov tshwj xeeb rheological nkhaus ntawm cellulose ether tuaj yeem txhim kho cov nyhuv ntawm lub tshuab txau thiab ua kom yooj yim rau cov txheej txheem mortar tom ntej thiab ua tiav.

Txawm hais tias muaj txiaj ntsig zoo ntawm cellulose ethers hauv GSP daim ntawv thov, nws tuaj yeem ua rau muaj peev xwm ua rau cov pob qhuav qhuav thaum txau. Cov pob zeb uas tsis muaj dej no tseem hu ua clumping lossis caking, thiab lawv tuaj yeem cuam tshuam rau qib thiab ua tiav ntawm cov mortar. Agglomeration tuaj yeem txo qhov chaw ua haujlwm thiab nce tus nqi ntawm kev ua haujlwm siab gypsum khoom siv. Txhawm rau kom nkag siab zoo dua cov txiaj ntsig ntawm cellulose ethers ntawm kev tsim cov pob hauv GSP, peb tau tshawb fawb los sim txheeb xyuas cov khoom lag luam cuam tshuam uas cuam tshuam rau lawv qhov tsim. Raws li cov txiaj ntsig ntawm txoj kev tshawb no, peb tau tsim cov khoom lag luam cellulose ether nrog kev txo qis rau agglomerate thiab ntsuas lawv hauv kev siv tswv yim.

Cov lus tseem ceeb: cellulose ether; gypsum tshuab txau plaster; tawg tus nqi; particle morphology

1. Taw qhia

Cov dej-soluble cellulose ethers tau ua tiav siv hauv gypsum-based tshuab-sprayed plasters (GSP) los tswj cov dej xav tau, txhim kho dej tuav thiab txhim kho cov khoom rheological ntawm mortars. Yog li ntawd, nws yuav pab txhim kho kev ua tau zoo ntawm cov mortar ntub, yog li ua kom ntseeg tau tias yuav tsum muaj zog ntawm cov tshuaj khib. Vim tias nws cov khoom lag luam zoo thiab ib puag ncig zoo, cov khoom siv qhuav GSP tau dhau los ua cov khoom siv sab hauv tsev thoob plaws Tebchaws Europe dhau 20 xyoo dhau los.

Machinery rau kev sib tov thiab tshuaj tsuag qhuav-blend GSP tau ua tiav kev lag luam rau ntau xyoo lawm. Txawm hais tias qee qhov kev ua haujlwm ntawm cov khoom siv los ntawm cov tuam txhab sib txawv sib txawv, txhua qhov kev lag luam muaj cov tshuab txau tso cai rau lub sijhawm tsis txaus siab rau cov dej sib tov nrog cellulose ether-muaj gypsum qhuav-siv tshuaj khib. Feem ntau, tag nrho cov txheej txheem sib xyaw tsuas siv ob peb feeb xwb. Tom qab sib tov, lub mortar ntub yog pumped los ntawm tus xa hose thiab sprayed mus rau lub substrate phab ntsa. Tag nrho cov txheej txheem ua tiav hauv ib feeb. Txawm li cas los xij, nyob rau lub sijhawm luv luv, cellulose ethers yuav tsum tau yaj tag nrho txhawm rau txhim kho lawv cov khoom hauv daim ntawv thov. Ntxiv cov khoom zoo hauv av cellulose ether rau gypsum mortar formulations ua kom tiav kev tawg thaum lub sij hawm txau cov txheej txheem no.

Cov av cellulose ether ua kom zoo sib xws sai sai ntawm kev sib cuag nrog dej thaum muaj kev ntxhov siab hauv lub tshuab txau. Qhov ceev ceev viscosity nce tshwm sim los ntawm kev sib cais ntawm cellulose ether ua rau muaj teeb meem nrog cov dej ntub dej ntawm cov gypsum cementitious cov ntaub ntawv. Raws li cov dej pib tuab, nws dhau los ua kua dej tsawg thiab tsis tuaj yeem nkag mus rau hauv cov pores me me ntawm cov gypsum hais. Tom qab nkag mus rau hauv lub qhov hws yog thaiv, cov txheej txheem ntub dej ntawm cov cementitious cov ntaub ntawv los ntawm dej yog ncua. Lub sij hawm sib xyaw hauv lub sprayer yog luv dua li lub sij hawm yuav tsum tau ua kom ntub cov gypsum hais, uas ua rau tsim cov hmoov qhuav clumps nyob rau hauv tshiab ntub mortar. Thaum cov clumps no tau tsim, lawv cuam tshuam qhov kev ua haujlwm ntawm cov neeg ua haujlwm hauv cov txheej txheem tom ntej: leveling mortar nrog clumps yog teeb meem heev thiab siv sijhawm ntau dua. Txawm tias tom qab lub mortar tau teem, thawj zaug tsim clumps yuav tshwm sim. Piv txwv li, npog cov clumps sab hauv thaum lub sij hawm tsim kho yuav ua rau cov tsos ntawm qhov tsaus ntuj nyob rau theem tom ntej, uas peb tsis xav pom.

Txawm hais tias cellulose ethers tau siv los ua cov khoom siv ntxiv hauv GSP tau ntau xyoo, lawv cov txiaj ntsig ntawm kev tsim cov pob zeb tsis muaj dej tsis tau kawm ntau txog tam sim no. Kab lus no nthuav tawm txoj hauv kev uas tuaj yeem siv los nkag siab lub hauv paus ua rau agglomeration los ntawm cellulose ether foundations.

2. Yog vim li cas rau kev tsim ntawm unwetted clumps nyob rau hauv GSP

2.1 Kev ntub dej ntawm plaster-based plasters

Nyob rau theem pib ntawm kev tsim cov kev tshawb fawb, ntau lub hauv paus ua rau tsim cov clumps hauv CSP tau sib sau ua ke. Tom ntej no, los ntawm kev tshuaj xyuas computer-pab, qhov teeb meem yog tsom mus rau seb puas muaj cov tswv yim daws teeb meem. Los ntawm cov haujlwm no, qhov kev daws teeb meem zoo tshaj plaws rau kev tsim cov agglomerates hauv GSP tau raug tshuaj xyuas ua ntej. Los ntawm ob qho tib si kev lag luam thiab kev xav txog kev lag luam, txoj hauv kev ntawm kev hloov cov ntub dej ntawm gypsum hais los ntawm kev kho saum npoo yog txiav tawm. Los ntawm qhov kev xav ntawm kev lag luam, lub tswv yim ntawm kev hloov cov cuab yeej uas twb muaj lawm nrog cov cuab yeej siv tshuaj tsuag nrog cov khoom sib xyaw tshwj xeeb uas tuaj yeem ua kom muaj kev sib xyaw txaus ntawm cov dej thiab tshuaj khib.

Lwm qhov kev xaiv yog siv cov ntaub ntub dej ua cov khoom siv ntxiv hauv gypsum plaster formulations thiab peb pom muaj patent rau qhov no lawm. Txawm li cas los xij, qhov sib ntxiv ntawm cov tshuaj ntxiv no inevitably cuam tshuam rau kev ua haujlwm ntawm plaster. Qhov tseem ceeb tshaj, nws hloov lub cev lub cev ntawm lub mortar, tshwj xeeb tshaj yog hardness thiab lub zog. Yog li peb tsis tau delve tob rau hauv nws. Tsis tas li ntawd, qhov sib ntxiv ntawm cov tshuaj ntub dej kuj tseem suav tias yog qhov ua rau muaj kev cuam tshuam tsis zoo rau ib puag ncig.

Xav tias cellulose ether twb yog ib feem ntawm gypsum-raws li plaster formulation, optimizing cellulose ether nws tus kheej yog qhov zoo tshaj plaws tov uas yuav xaiv tau. Nyob rau tib lub sijhawm, nws yuav tsum tsis txhob cuam tshuam cov dej tuav cov khoom lossis cuam tshuam rau cov khoom rheological ntawm plaster hauv kev siv. Raws li cov kev xav yav dhau los hais tias tiam ntawm cov hmoov tsis-wetted hauv GSP yog vim qhov nce nrawm heev hauv cov viscosity ntawm cellulose ethers tom qab kev sib cuag nrog dej thaum nplawm, tswj cov yam ntxwv ntawm kev sib cais ntawm cellulose ethers los ua lub hom phiaj tseem ceeb ntawm peb txoj kev kawm. .

2.2 Dissolving lub sij hawm ntawm cellulose ether

Ib txoj hauv kev yooj yim los ua kom qeeb tus nqi ntawm cov cellulose ethers yog siv cov khoom qib granular. Lub ntsiab qhov tsis zoo ntawm kev siv txoj hauv kev no hauv GSP yog tias cov khoom uas ntxhib dhau tsis yaj tag nrho hauv lub qhov rais 10-thib ob hauv lub tshuab txau, uas ua rau poob dej tuav. Tsis tas li ntawd, qhov o ntawm undissolved cellulose ether nyob rau theem tom ntej yuav ua rau thickening tom qab plastering thiab cuam tshuam rau kev tsim kho, uas yog qhov peb tsis xav pom.

Lwm qhov kev xaiv los txo qhov kev sib cais ntawm cellulose ethers yog reversibly crosslink ntawm cellulose ethers nrog glyoxal. Txawm li cas los xij, txij li cov tshuaj tiv thaiv crosslinking yog pH-tswj, qhov kev sib cais ntawm cellulose ethers yog nyob ntawm pH ntawm cov dej nyob ib puag ncig. Tus nqi pH ntawm GSP system tov nrog slaked txiv qaub yog siab heev, thiab cross-linking bonds ntawm glyoxal rau saum npoo yog qhib sai sai tom qab hu rau dej, thiab cov viscosity pib nce sai. Yog li ntawd, xws li tshuaj kho mob tsis tuaj yeem ua lub luag haujlwm hauv kev tswj cov kev sib cais ntawm GSP.

Lub sijhawm so ntawm cellulose ethers kuj nyob ntawm lawv cov particle morphology. Txawm li cas los xij, qhov tseeb no tsis tau txais kev mloog ntau txog tam sim no, txawm hais tias cov nyhuv tseem ceeb heev. Lawv muaj qhov tsis tu ncua linear dissolution tus nqi [kg / (m2•s)], yog li lawv qhov kev sib cais thiab viscosity build-up yog proportional rau qhov muaj. Tus nqi no tuaj yeem sib txawv heev nrog kev hloov pauv hauv morphology ntawm cellulose hais. Hauv peb cov kev suav suav suav tias yog tag nrho viscosity (100%) mus txog tom qab 5 vib nas this ntawm kev sib tov sib xyaw.

Kev suav ntawm qhov sib txawv particle morphologies tau pom tias cov khoom kheej kheej muaj viscosity ntawm 35% ntawm qhov kawg viscosity ntawm ib nrab ntawm lub sijhawm sib xyaw. Nyob rau tib lub sijhawm, pas nrig-zoo li cellulose ether hais tuaj yeem ncav cuag 10%. Lub disc-zoo li hais tias nyuam qhuav pib yaj tom qab2.5 vib nas this.

Kuj suav nrog yog cov yam ntxwv zoo tshaj plaws solubility rau cellulose ethers hauv GSP. Ncua thawj viscosity build-up rau ntau tshaj 4.5 vib nas this. Tom qab ntawd, cov viscosity tau nce sai heev kom ncav cuag qhov kawg viscosity hauv 5 vib nas this ntawm kev sib tov sib xyaw. Nyob rau hauv GSP, xws li ncua sij hawm dissolution lub sij hawm ntev tso cai rau lub kaw lus kom tsis muaj viscosity, thiab cov dej ntxiv tuaj yeem ntub cov gypsum thiab nkag mus rau hauv lub qhov hws ntawm cov khoom tsis muaj kev cuam tshuam.

3. Particle morphology ntawm cellulose ether

3.1 Kev ntsuas particle morphology

Txij li cov duab ntawm cellulose ether hais muaj qhov cuam tshuam loj heev rau kev solubility, nws yog thawj zaug uas yuav tsum tau txiav txim siab txog qhov tsis piav qhia txog cov duab ntawm cellulose ether hais, thiab tom qab ntawd txhawm rau txheeb xyuas qhov sib txawv ntawm qhov tsis ntub, qhov tsim ntawm agglomerates yog qhov tshwj xeeb tshaj yog qhov ntsuas. .

Peb tau txais cov particle morphology ntawm cellulose ether los ntawm dynamic duab tsom xam txheej txheem. Lub particle morphology ntawm cellulose ethers tuaj yeem ua tus yam ntxwv zoo siv SYMPATEC cov duab ntsuas (ua hauv lub teb chaws Yelemees) thiab cov cuab yeej siv software tshwj xeeb. Qhov tseem ceeb tshaj plaws particle zoo tsis tau pom yog qhov nruab nrab ntev ntawm fibers qhia raws li LEFI (50,3) thiab qhov nruab nrab txoj kab uas hla qhia raws li DIFI (50,3). Fiber nruab nrab ntev cov ntaub ntawv raug suav hais tias yog tag nrho ntev ntawm ib qho kev nthuav tawm cellulose ether particle.

Feem ntau particle loj faib cov ntaub ntawv xws li qhov nruab nrab fiber ntau txoj kab uas hla DIFI tej zaum yuav xam raws li tus naj npawb ntawm hais (los ntawm 0), ntev (denoted los ntawm 1), cheeb tsam (denoted los ntawm 2) los yog ntim (denoted los ntawm 3). Tag nrho cov ntaub ntawv ntsuas particle nyob rau hauv daim ntawv no yog raws li ntim thiab yog li ntawd qhia nrog ib tug 3 suffix. Piv txwv li, hauv DIFI (50,3), 3 txhais tau hais tias qhov ntim ntim, thiab 50 txhais tau hais tias 50% ntawm qhov loj me me faib nkhaus yog me dua li tus nqi qhia, thiab lwm yam 50% loj dua li qhov qhia txog tus nqi. Cellulose ether particle cov ntaub ntawv yog muab nyob rau hauv micrometers (µm).

3.2 Cellulose ether tom qab particle morphology optimization

Noj mus rau hauv tus account cov nyhuv ntawm particle nto, particle dissolution lub sij hawm ntawm cellulose ether hais nrog ib tug pas nrig-zoo li particle zoo nyob ntawm qhov nruab nrab fiber inch DIFI (50,3). Raws li qhov kev xav no, kev txhim kho kev ua haujlwm ntawm cellulose ethers yog tsom rau kev tau txais cov khoom lag luam nrog qhov loj dua qhov nruab nrab fiber ntau DIFI (50,3) txhawm rau txhim kho cov hmoov av solubility.

Txawm li cas los xij, qhov nce ntawm qhov nruab nrab fiber ntau ntev DIFI (50,3) tsis xav tias yuav tsum tau nrog rau qhov nce ntawm qhov nruab nrab particle loj. Kev nce ob qho tib si ua ke yuav ua rau cov khoom loj dhau los ua kom yaj tag nrho hauv lub sijhawm 10-thib ob agitation ntawm cov tshuab txau.

Yog li, qhov zoo tshaj plaws hydroxyethylmethylcellulose (HEMC) yuav tsum muaj qhov loj dua qhov nruab nrab fiber ntau DIFI (50,3) thaum tswj qhov nruab nrab fiber ntau LEFI (50,3). Peb siv cov txheej txheem tshiab ntawm cellulose ether los tsim ib qho kev txhim kho HEMC. Cov duab ntawm cov dej-soluble cellulose ether tau los ntawm cov txheej txheem tsim khoom no yog txawv kiag li ntawm cov duab ntawm cov cellulose siv los ua cov khoom siv raw rau kev tsim khoom. Hauv lwm lo lus, cov txheej txheem tsim khoom tso cai rau cov qauv tsim qauv ntawm cellulose ether ua ywj siab ntawm nws cov khoom siv raw.

Peb scanning electron microscope dluab: ib qho ntawm cov cellulose ether ua los ntawm cov txheej txheem txheem, thiab ib qho ntawm cellulose ether tsim los ntawm cov txheej txheem tshiab nrog ib tug loj txoj kab uas hla ntawm DIFI (50,3) tshaj cov pa txheej txheem cov khoom. Tsis tas li ntawd qhia yog cov morphology ntawm finely av cellulose siv nyob rau hauv zus tau tej cov ob cov khoom.

Muab piv cov electron micrographs ntawm cellulose thiab cellulose ether ua los ntawm cov txheej txheem txheem, nws yog ib qho yooj yim mus nrhiav tau hais tias ob tug muaj xws li morphological yam ntxwv. Qhov loj ntawm cov khoom nyob rau hauv ob qho tib si duab nthuav tawm feem ntau ntev, nyias cov qauv, qhia tias cov yam ntxwv morphological tseem ceeb tsis tau hloov txawm tias tom qab cov tshuaj tiv thaiv tau tshwm sim. Nws yog tseeb hais tias cov particle morphology yam ntxwv ntawm cov tshuaj tiv thaiv cov khoom yog heev correlated nrog raw cov ntaub ntawv.

Nws tau pom tias cov yam ntxwv morphological ntawm cellulose ether tsim los ntawm cov txheej txheem tshiab yog qhov sib txawv, nws muaj qhov loj dua qhov nruab nrab txoj kab uas hla DIFI (50,3), thiab feem ntau nthuav tawm puag ncig luv luv thiab tuab cov duab, thaum cov khoom nyias nyias thiab ntev. nyob rau hauv cellulose raw khoom Yuav luag tuag.

Daim duab no dua qhia tau hais tias cov particle morphology ntawm cellulose ethers uas ua los ntawm cov txheej txheem tshiab yog tsis muaj feem xyuam rau lub morphology ntawm cellulose raw khoom - qhov kev sib txuas ntawm morphology ntawm raw khoom thiab cov khoom zaum kawg tsis muaj lawm.

4. Cov txiaj ntsig ntawm HEMC particle morphology ntawm kev tsim cov pob zeb tsis muaj dej hauv GSP

GSP tau raug sim nyob rau hauv daim ntawv thov daim ntawv thov kom paub tseeb tias peb qhov kev xav txog kev ua haujlwm (uas siv cov khoom siv cellulose ether nrog lub dav dav dav DIFI (50,3) yuav txo qis qhov tsis xav tau agglomeration) yog lawm. HEMCs nrog cov kab nruab nrab DIFI (50,3) xws li 37 µm txog 52 µm tau siv rau hauv cov kev sim no. Txhawm rau txo qis kev cuam tshuam ntawm lwm yam uas tsis yog particle morphology, gypsum plaster puag thiab tag nrho lwm cov khoom ntxiv tau khaws cia tsis hloov pauv. Lub viscosity ntawm cellulose ether tau khaws cia tsis tu ncua thaum lub sijhawm kuaj (60,000mPa.s, 2% aqueous tov, ntsuas nrog HAAKE rheometer).

Ib qho kev lag luam muaj gypsum sprayer (PFT G4) tau siv los txau rau hauv daim ntawv thov kev sim. Tsom ntsoov rau kev ntsuam xyuas qhov tsim ntawm unwetted clumps ntawm gypsum mortar tam sim ntawd tom qab nws tau siv rau phab ntsa. Kev soj ntsuam ntawm clumping nyob rau theem no thoob plaws hauv cov txheej txheem thov plastering yuav zoo tshaj plaws qhia qhov sib txawv ntawm cov khoom ua tau zoo. Hauv kev sim, cov neeg ua haujlwm paub txog qhov xwm txheej clumping, nrog 1 yog qhov zoo tshaj plaws thiab 6 yog qhov phem tshaj.

Cov qhabnias xeem tau qhia meej txog kev sib raug zoo ntawm qhov nruab nrab fiber ntau txoj kab uas hla DIFI (50,3) thiab cov qhab nia ua tau zoo. Raws li peb qhov kev xav tias cov khoom lag luam cellulose ether nrog DIFI loj dua (50,3) tau ua tiav cov khoom me me DIFI (50,3), qhov qhab nia nruab nrab rau DIFI (50,3) ntawm 52 µm yog 2 (zoo), thaum cov uas muaj DIFI ( 50,3) ntawm 37µm thiab 40µm tau qhab nia 5 (tsis ua haujlwm).

Raws li peb xav tau, tus cwj pwm clumping hauv GSP daim ntawv thov nyob ntawm qhov nruab nrab txoj kab uas hla DIFI (50,3) ntawm cellulose ether siv. Ntxiv mus, nws tau hais nyob rau hauv kev sib tham yav dhau los hais tias ntawm tag nrho cov morphological tsis DIFI (50,3) muaj zog cuam tshuam lub sij hawm dissolution ntawm cellulose ether hmoov. Qhov no qhia tau hais tias cellulose ether dissolution lub sij hawm, uas yog heev correlated nrog particle morphology, thaum kawg cuam tshuam cov tsim ntawm clumps nyob rau hauv GSP. Qhov loj dua DIFI (50,3) ua rau lub sij hawm tawg ntev ntawm cov hmoov, uas txo qis txoj hauv kev ntawm agglomeration. Txawm li cas los xij, lub sij hawm ua hmoov qhuav ntev dhau lawm yuav ua rau nws nyuaj rau cov cellulose ether kom yaj tag nrho hauv lub sijhawm nplawm ntawm cov khoom siv txau.

Cov khoom HEMC tshiab nrog qhov ua kom zoo dua qhov kev sib cais vim qhov loj dua qhov nruab nrab fiber ntau DIFI (50,3) tsis tsuas yog muaj cov dej ntub dej zoo dua ntawm cov hmoov gypsum (raws li pom nyob rau hauv kev ntsuam xyuas clumping), tab sis kuj tsis cuam tshuam rau cov dej tuav kev ua haujlwm ntawm cov khoom. Cov dej tuav ntsuas raws li EN 459-2 yog qhov txawv ntawm HEMC cov khoom ntawm tib viscosity nrog DIFI (50,3) los ntawm 37µm txog 52µm. Tag nrho cov kev ntsuas tom qab 5 feeb thiab 60 feeb poob nyob rau hauv qhov yuav tsum tau muaj nyob rau hauv daim duab.

Txawm li cas los xij, nws kuj tau lees paub tias yog DIFI (50,3) loj dhau, cov cellulose ether hais yuav tsis yaj tag. Qhov no tau pom thaum kuaj DIFI (50,3) ntawm 59 µM cov khoom. Nws qhov ntsuas dej tuav tau tom qab 5 feeb thiab tshwj xeeb tshaj yog tom qab 60 feeb ua tsis tau raws li qhov xav tau yam tsawg kawg nkaus.

5. Cov ntsiab lus

Cellulose ethers yog ib qho tseem ceeb additives nyob rau hauv GSP formulations. Kev tshawb fawb thiab kev tsim khoom lag luam ua haujlwm ntawm no saib qhov kev sib raug zoo ntawm cov particle morphology ntawm cellulose ethers thiab tsim ntawm unwetted clumps (hu ua clumping) thaum mechanically sprayed. Nws yog raws li qhov kev xav ntawm kev ua hauj lwm mechanism uas lub sij hawm dissolution ntawm cellulose ether hmoov cuam tshuam rau wetting ntawm gypsum hmoov los ntawm dej thiab yog li cuam tshuam rau cov tsim ntawm clumps.

Lub sij hawm dissolution nyob ntawm qhov particle morphology ntawm cellulose ether thiab tuaj yeem tau txais los ntawm cov cuab yeej ntsuas duab digital. Nyob rau hauv GSP, cellulose ethers nrog ib tug loj nruab nrab txoj kab uas hla ntawm DIFI (50,3) muaj optimized hmoov dissolution yam ntxwv, tso cai rau ntau lub sij hawm rau cov dej kom huv si ntub cov gypsum hais, yog li ua rau optimum anti-agglomeration. Hom cellulose ether no yog tsim los siv cov txheej txheem tsim khoom tshiab, thiab nws daim ntawv particle tsis nyob ntawm daim ntawv qub ntawm cov khoom siv raw rau kev tsim khoom.

Qhov nruab nrab fiber ntau txoj kab uas hla DIFI (50,3) muaj ib qho tseem ceeb heev ntawm clumping, uas tau raug txheeb xyuas los ntawm kev ntxiv cov khoom no mus rau lub lag luam muaj tshuab-txhaj tshuaj gypsum puag rau ntawm qhov chaw txau. Tsis tas li ntawd, cov kev ntsuas tshuaj tsuag no tau lees paub peb cov txiaj ntsig hauv kev sim: qhov ua tau zoo tshaj plaws ntawm cov khoom siv cellulose ether nrog DIFI loj (50,3) tau soluble tag nrho hauv lub sijhawm ntawm GSP agitation. Yog li ntawd, cov khoom lag luam cellulose ether nrog cov khoom zoo tshaj plaws los tiv thaiv kev ua haujlwm tom qab kev txhim kho cov duab zoo tseem tuav cov dej qub qub.