Kev tshawb fawb txog Rheological ntawm Hydroxypropyl Methylcellulose (HPMC) thickener systems yog qhov tseem ceeb rau kev nkag siab txog lawv tus cwj pwm hauv ntau yam kev siv, xws li tshuaj mus rau zaub mov thiab tshuaj pleev ib ce. HPMC yog ib qho cellulose ether derivative siv dav ua tus neeg sawv cev thickening, stabilizer, thiab emulsifier vim nws muaj peev xwm hloov kho cov khoom rheological ntawm cov tshuaj thiab cov suspensions.
1. Kev Ntsuas Viscosity:
Viscosity yog ib qho ntawm cov khoom rheological tseem ceeb tshaj plaws uas tau kawm hauv HPMC systems. Ntau yam txheej txheem xws li rotational viscometry, capillary viscometry, thiab oscillatory rheometry yog siv los ntsuas viscosity.
Cov kev tshawb fawb no piav qhia txog qhov cuam tshuam ntawm cov yam xws li HPMC concentration, molecular weight, degree of substitution, temperature, thiab shear rate rau viscosity.
Kev nkag siab txog viscosity yog qhov tseem ceeb vim nws txiav txim siab txog tus cwj pwm ntws, kev ruaj khov, thiab kev siv tau ntawm HPMC thickened systems.
2. Kev coj cwj pwm ua kom nyias nyias:
Cov kev daws teeb meem HPMC feem ntau ua rau pom kev coj tus cwj pwm shear-thinning, txhais tau tias lawv cov viscosity txo qis nrog kev nce ntxiv ntawm shear.
Cov kev tshawb fawb txog rheological tshawb nrhiav txog qhov dav ntawm shear-thinning thiab nws nyob ntawm cov yam xws li polymer concentration thiab kub.
Kev piav qhia txog tus cwj pwm shear-thinning yog qhov tseem ceeb rau cov ntawv thov xws li cov txheej txheem thiab cov nplaum, qhov twg ntws thaum lub sijhawm thov thiab kev ruaj khov tom qab thov yog qhov tseem ceeb.
3. Thixotropy:
Thixotropy yog hais txog lub sijhawm rov qab los ntawm viscosity tom qab tshem tawm ntawm kev ntxhov siab shear. Ntau lub tshuab HPMC qhia txog tus cwj pwm thixotropic, uas yog qhov zoo hauv cov ntawv thov uas xav tau kev tswj hwm kev ntws thiab kev ruaj khov.
Cov kev tshawb fawb rheological suav nrog kev ntsuas qhov rov qab los ntawm viscosity dhau sijhawm tom qab raug lub kaw lus rau kev ntxhov siab shear.
Kev nkag siab txog thixotropy pab tsim cov khoom xws li xim, qhov twg kev ruaj khov thaum khaws cia thiab yooj yim siv yog qhov tseem ceeb.
4. Kev sib xyaw ua ke:
Thaum muaj ntau dua lossis nrog cov khoom ntxiv tshwj xeeb, HPMC cov kev daws teeb meem tuaj yeem dhau los ua gelation, tsim cov qauv network.
Cov kev tshawb fawb txog rheological tshawb nrhiav tus cwj pwm gelation txog cov yam xws li concentration, kub, thiab pH.
Kev tshawb fawb txog gelation yog qhov tseem ceeb rau kev tsim cov tshuaj uas tso tawm tas mus li thiab tsim cov khoom lag luam gel ruaj khov hauv kev lag luam zaub mov thiab kev saib xyuas tus kheej.
5. Kev piav qhia txog cov qauv:
Cov txheej txheem xws li kev tawg ntawm lub kaum sab xis me me (SAXS) thiab rheo-SAXS muab kev nkag siab rau hauv microstructure ntawm HPMC systems.
Cov kev tshawb fawb no qhia cov ntaub ntawv hais txog cov qauv polymer chain, kev coj tus cwj pwm sib sau ua ke, thiab kev sib cuam tshuam nrog cov tshuaj yaj.
Kev nkag siab txog cov yam ntxwv ntawm cov qauv pab tau rau kev kwv yees tus cwj pwm macroscopic rheological thiab ua kom zoo dua cov qauv rau cov khoom xav tau.
6. Kev Tshawb Fawb Txog Kev Siv Tshuab Dynamic (DMA):
DMA ntsuas cov khoom viscoelastic ntawm cov ntaub ntawv nyob rau hauv oscillatory deformation.
Cov kev tshawb fawb txog rheological siv DMA piav qhia txog cov kev ntsuas xws li storage modulus (G'), loss modulus (G"), thiab complex viscosity ua haujlwm ntawm zaus thiab kub.
DMA muaj txiaj ntsig zoo rau kev piav qhia txog tus cwj pwm zoo li khoom khov thiab kua dej ntawm HPMC gels thiab pastes.
7. Kev Kawm Tshwj Xeeb rau Daim Ntawv Thov:
Cov kev tshawb fawb txog rheological yog tsim los rau cov ntawv thov tshwj xeeb xws li cov ntsiav tshuaj kws kho mob, qhov twg HPMC siv los ua cov khoom sib txuas, lossis hauv cov khoom noj xws li cov kua ntses thiab cov khaub ncaws hnav, qhov twg nws ua haujlwm ua cov khoom tuab thiab stabilizer.
Cov kev tshawb fawb no ua kom zoo dua cov qauv HPMC rau cov yam ntxwv ntws, cov qauv, thiab kev ruaj khov ntawm txee, ua kom ntseeg tau tias cov khoom ua tau zoo thiab kev lees txais ntawm cov neeg siv khoom.
Cov kev tshawb fawb txog rheological ua lub luag haujlwm tseem ceeb hauv kev nkag siab txog tus cwj pwm nyuaj ntawm HPMC thickener systems. Los ntawm kev piav qhia txog viscosity, shear-thinning, thixotropy, gelation, cov yam ntxwv ntawm cov qauv, thiab cov khoom siv tshwj xeeb, cov kev tshawb fawb no pab txhawb kev tsim thiab kev ua kom zoo dua ntawm HPMC-based formulations thoob plaws ntau yam lag luam.
Lub sijhawm tshaj tawm: Tsib Hlis-10-2024