Hydroxypropyl methylcellulose (HPMC) yog ib qho tseem ceeb chemical additive, dav siv nyob rau hauv ntau lub teb xws li kev tsim kho, tshuaj, zaub mov, thiab tshuaj pleev ib ce. Nws muaj cov thickening zoo, gelling, emulsifying, film-forming, thiab bonding zog, thiab muaj tej yam stability rau kub thiab pH. Lub solubility ntawm HPMC yog ib qho ntawm cov teeb meem tseem ceeb hauv kev siv. Kev nkag siab txog txoj kev sib cais kom raug yog qhov tseem ceeb los xyuas kom meej nws cov kev ua tau zoo.
1. Cov khoom tawg yooj yim ntawm HPMC
Hydroxypropyl methylcellulose yog cov dej tsis-ionic-soluble cellulose ether uas tuaj yeem yaj hauv dej txias lossis dej kub los tsim cov kua nplaum los yog cov kua nplaum. Nws solubility feem ntau cuam tshuam los ntawm qhov kub thiab txias. Nws yooj yim dua rau yaj hauv dej txias thiab yooj yim los ua ib qho colloid hauv dej kub. HPMC muaj thermal gelation, uas yog, nws muaj kev tsis zoo solubility ntawm qhov kub siab dua, tab sis tuaj yeem yaj tag nrho thaum qhov kub thiab txias. HPMC muaj qhov sib txawv molecular hnyav thiab viscosities, yog li thaum lub sij hawm dissolution txheej txheem, tus qauv HPMC tsim nyog yuav tsum tau xaiv raws li cov khoom yuav tsum tau.
2. Txoj kev sib cais ntawm HPMC
Cov txheej txheem dej txias dispersion
Cov txheej txheem dej txias dispersion yog HPMC feem ntau siv txoj kev sib cais thiab tsim nyog rau feem ntau daim ntawv thov scenarios. Cov kauj ruam tshwj xeeb yog raws li nram no:
Npaj dej txias: Ncuav cov dej txias uas xav tau rau hauv lub thawv sib tov. Cov dej kub feem ntau pom zoo kom qis dua 40 ° C kom tsis txhob HPMC los ntawm kev tsim cov pob hauv qhov kub siab.
Maj mam ntxiv HPMC: Maj mam ntxiv HPMC hmoov thiab txuas ntxiv stirring. Txhawm rau kom tsis txhob muaj cov hmoov agglomeration, qhov tsim nyog stirring ceev yuav tsum tau siv los xyuas kom meej tias HPMC tuaj yeem sib npaug sib npaug hauv dej.
Sawv ntsug thiab yaj: Tom qab HPMC tau tawg mus rau hauv dej txias, nws yuav tsum tau sawv ntsug rau ib lub sijhawm kom yaj tag. Feem ntau, nws raug tso tseg rau 30 feeb mus rau ob peb teev, thiab lub sijhawm tshwj xeeb txawv nyob ntawm tus qauv HPMC thiab dej kub. Thaum lub sij hawm sawv ntsug, HPMC yuav maj mam yaj los ua ib qho kev daws teeb meem.
Cov txheej txheem dej kub ua ntej dissolution
Cov txheej txheem dej kub ua ntej-solution yog tsim rau qee tus qauv HPMC uas muaj viscosity siab lossis nyuaj kom yaj tag nrho hauv dej txias. Txoj kev no yog thawj zaug sib tov HPMC hmoov nrog ib feem ntawm cov dej kub los ua ib qho muab tshuaj txhuam, thiab tom qab ntawd sib tov nrog dej txias kom thaum kawg tau txais cov tshuaj sib xws. Cov kauj ruam tshwj xeeb yog raws li nram no:
Cov dej kub: Kub ib qho dej kom txog li 80 ° C thiab hliv rau hauv lub thawv sib tov.
Ntxiv HPMC hmoov: Ncuav cov hmoov HPMC rau hauv dej kub thiab do thaum pouring los ua ib qho kev sib tov sib xyaw. Hauv dej kub, HPMC yuav yaj ib ntus thiab tsim cov khoom zoo li gel.
Ntxiv dej txias rau dilute: Tom qab muab tshuaj txhuam sib tov txias, maj mam ntxiv dej txias kom dilute nws thiab txuas ntxiv stirring kom txog thaum nws tag nrho yaj mus rau hauv lub pob tshab los yog translucent tov.
Organic solvent dispersion method
Qee zaum, txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau HPMC lossis txhim kho cov txiaj ntsig kev sib cais ntawm qee cov ntawv thov tshwj xeeb, cov kuab tshuaj organic tuaj yeem siv los sib xyaw nrog dej kom yaj HPMC. Piv txwv li, cov kuab tshuaj organic xws li ethanol thiab acetone tuaj yeem siv los rhuav tshem HPMC ua ntej, thiab tom qab ntawd dej tuaj yeem ntxiv los pab HPMC yaj sai dua. Txoj kev no feem ntau yog siv rau hauv kev tsim khoom ntawm qee cov khoom hnyav, xws li cov coatings thiab xim.
Kev sib xyaw qhuav
Txoj kev sib xyaw qhuav yog tsim rau kev lag luam loj loj. HPMC feem ntau yog ua ntej qhuav sib xyaw nrog lwm cov ntaub ntawv hmoov (xws li cov cement, gypsum, thiab lwm yam), thiab tom qab ntawd dej ntxiv rau sib tov thaum siv. Txoj kev no ua kom yooj yim rau cov kauj ruam ua haujlwm thiab zam qhov teeb meem agglomeration thaum HPMC yaj ib leeg, tab sis yuav tsum muaj kev sib tov txaus tom qab ntxiv dej kom paub meej tias HPMC tuaj yeem sib npaug thiab ua lub luag haujlwm thickening.
3. Cov yam ntxwv cuam tshuam rau HPMC kev sib cais
Kub: Lub solubility ntawm HPMC yog rhiab heev rau kub. Qhov kub thiab txias yog qhov tsim nyog rau nws qhov tawg thiab tawg hauv dej, thaum qhov kub siab tau yooj yim ua rau HPMC tsim cov colloids, cuam tshuam nws cov kev tawg tag. Yog li ntawd, nws yog feem ntau pom zoo kom siv dej txias los yog tswj cov dej kub hauv qab 40 ° C thaum dissolving HPMC.
Stirring ceev: Kev nplawm kom zoo tuaj yeem zam HPMC agglomeration, yog li ua kom nrawm nrawm. Txawm li cas los xij, nrawm nrawm nrawm tuaj yeem qhia ntau tus npuas thiab cuam tshuam rau qhov sib xws ntawm cov tshuaj. Yog li ntawd, hauv kev ua haujlwm tiag tiag, qhov tsim nyog stirring ceev thiab cov khoom siv yuav tsum raug xaiv.
Dej zoo: impurities, hardness, pH nqi, thiab lwm yam hauv dej yuav cuam tshuam rau solubility ntawm HPMC. Tshwj xeeb, calcium thiab magnesium ions hauv cov dej tawv tuaj yeem ua rau HPMC thiab cuam tshuam rau nws cov solubility. Yog li ntawd, kev siv cov dej ntshiab los yog dej mos yuav pab txhim kho kev ua kom tiav ntawm HPMC.
HPMC qauv thiab qhov hnyav molecular: Cov qauv sib txawv ntawm HPMC sib txawv hauv kev sib cais ceev, viscosity thiab kub dissolution. HPMC nrog siab molecular hnyav dissolves maj mam, muaj kua viscosity siab, thiab siv sij hawm ntev dua kom yaj tag. Xaiv tus qauv HPMC txoj cai tuaj yeem txhim kho kev ua kom tiav thiab ua tau raws li cov kev cai sib txawv.
4. Tej teeb meem thiab kev daws teeb meem hauv HPMC kev sib cais
Teeb meem agglomeration: Thaum HPMC yaj hauv dej, agglomeration tuaj yeem tsim yog tias cov hmoov tsis sib npaug. Txhawm rau zam qhov teeb meem no, HPMC yuav tsum tau muab ntxiv maj mam thaum lub sijhawm tawg thiab khaws cia ntawm qhov tsim nyog stirring ceev, thaum tsis txhob ntxiv HPMC hmoov ntawm qhov kub thiab txias.
Kev daws tsis sib xws: Yog tias qhov sib tov tsis txaus lossis lub sijhawm sawv ntsug tsis txaus, HPMC yuav tsis yaj tag, uas ua rau muaj kev daws tsis sib xws. Lub sijhawm no, lub sijhawm nplawm yuav tsum tau txuas ntxiv lossis lub sijhawm sawv ntsug yuav tsum tau nce ntxiv kom ntseeg tau tias muaj kev sib cais tiav.
Npuas teeb meem: Kev nplawm nrawm dhau los yog impurities hauv dej tuaj yeem ua kom paub ntau tus npuas, cuam tshuam qhov zoo ntawm cov tshuaj. Vim li no, nws raug nquahu kom tswj lub nplawm nrawm thaum tawg HPMC kom tsis txhob muaj npuas ntau dhau, thiab ntxiv cov defoamer yog tias tsim nyog.
Kev tawg ntawm HPMC yog qhov txuas tseem ceeb hauv nws daim ntawv thov. Mastering tus txheej txheem dissolution yog pab txhim kho cov khoom zoo thiab ntau lawm efficiency. Raws li ntau hom HPMC thiab daim ntawv thov yuav tsum tau, dej txias dispersion, dej kub pre-solution, organic solvent dispersion los yog qhuav mixing. Nyob rau tib lub sijhawm, kev saib xyuas yuav tsum tau them nyiaj rau kev tswj hwm yam xws li qhov kub thiab txias, nplawm nrawm thiab dej zoo thaum lub sij hawm tawg kom tsis txhob muaj teeb meem xws li agglomeration, npuas thiab tsis tiav dissolution. Los ntawm kev ua kom zoo dua qhov kev sib cais, nws tuaj yeem ua kom ntseeg tau tias HPMC tuaj yeem muab kev ua si tag nrho rau nws cov thickening thiab film-forming zog, muab cov kev daws teeb meem zoo rau ntau yam kev lag luam thiab kev siv niaj hnub.
Post lub sij hawm: Sep-30-2024