HPMC (hydroxypropyl methylcellulose) yog ib qho thickener thiab stabilizer uas feem ntau siv rau hauv cov ntaub ntawv tsim kho, coatings, tshuaj thiab khoom noj. HPMC 15 cps txhais tau tias nws cov viscosity yog 15 centipoise, uas yog qib viscosity qis.
1. Ua kom HPMC concentration ntau ntxiv
Txoj kev ncaj qha thiab zoo tshaj plaws los ua kom cov viscosity ntawm HPMC nce ntxiv yog kom nce nws cov concentration hauv cov tshuaj. Thaum cov feem loj ntawm HPMC nce ntxiv, cov viscosity ntawm cov tshuaj kuj tseem yuav nce ntxiv. Lub hauv paus ntawm txoj kev no yog tias HPMC ua rau cov viscosity ntawm cov tshuaj nce ntxiv los ntawm kev tsim cov qauv network peb-seem. Raws li tus lej ntawm HPMC molecules hauv cov tshuaj nce ntxiv, qhov ceev thiab lub zog ntawm cov qauv network kuj yuav nce ntxiv, yog li ua rau cov viscosity ntawm cov tshuaj nce ntxiv. Txawm li cas los xij, muaj kev txwv rau kev nce qhov concentration. Cov concentration ntau dhau ntawm HPMC yuav ua rau cov kua dej ntawm cov tshuaj txo qis, thiab tej zaum yuav cuam tshuam rau nws cov kev ua tau zoo hauv cov ntawv thov tshwj xeeb, xws li kev tsim kho thiab kev ua haujlwm.
2. Tswj qhov kub ntawm cov tshuaj
Kub muaj feem cuam tshuam loj heev rau qhov solubility thiab viscosity ntawm HPMC. Thaum kub qis dua, qhov viscosity ntawm HPMC kua yog siab dua; thaum kub siab dua, qhov viscosity ntawm HPMC kua yuav txo qis. Yog li ntawd, txo qhov kub ntawm cov kua kom raug thaum siv tuaj yeem ua rau qhov viscosity ntawm HPMC nce ntxiv. Nws yuav tsum tau sau tseg tias qhov solubility ntawm HPMC hauv cov kua yog txawv ntawm qhov kub sib txawv. Nws feem ntau yooj yim dua rau disperse hauv dej txias, tab sis nws siv sijhawm me ntsis kom yaj tag. Nws yaj sai dua hauv dej sov, tab sis qhov viscosity qis dua.
3. Hloov tus nqi pH ntawm cov kuab tshuaj
Qhov viscosity ntawm HPMC kuj tseem nkag siab rau tus nqi pH ntawm cov tshuaj. Nyob rau hauv qhov tsis muaj zog lossis ze-nruab nrab, qhov viscosity ntawm HPMC cov tshuaj yog qhov siab tshaj plaws. Yog tias tus nqi pH ntawm cov tshuaj deviates los ntawm qhov tsis muaj zog, qhov viscosity yuav txo qis. Yog li ntawd, qhov viscosity ntawm HPMC cov tshuaj tuaj yeem nce ntxiv los ntawm kev kho kom raug tus nqi pH ntawm cov tshuaj (piv txwv li, los ntawm kev ntxiv lub buffer lossis tus tswj acid-base). Txawm li cas los xij, hauv kev ua haujlwm tiag tiag, kev kho tus nqi pH yuav tsum ceev faj heev, vim tias kev hloov pauv loj yuav ua rau HPMC puas tsuaj lossis kev ua haujlwm puas tsuaj.
4. Xaiv cov tshuaj uas tsim nyog
Qhov solubility thiab viscosity ntawm HPMC hauv cov txheej txheem solvent sib txawv yog txawv. Txawm hais tias HPMC feem ntau yog siv rau hauv cov kua dej, qhov ntxiv ntawm qee cov organic solvents (xws li ethanol, isopropanol, thiab lwm yam) lossis cov ntsev sib txawv tuaj yeem hloov pauv cov saw hlau ntawm HPMC molecule, yog li cuam tshuam rau viscosity. Piv txwv li, ib qho me me ntawm cov organic solvent tuaj yeem txo qhov cuam tshuam ntawm cov dej molecules ntawm HPMC, yog li ua rau viscosity ntawm cov tshuaj nce ntxiv. Hauv kev ua haujlwm tshwj xeeb, nws yog qhov tsim nyog los xaiv cov organic solvents tsim nyog raws li daim ntawv thov tiag tiag.
5. Siv cov khoom pab ua kom tuab
Qee zaum, lwm yam khoom pab ua kom tuab tuaj yeem ntxiv rau HPMC kom ua tiav cov txiaj ntsig ntawm kev nce viscosity. Cov khoom pab ua kom tuab feem ntau suav nrog xanthan gum, guar gum, carbomer, thiab lwm yam. Cov khoom ntxiv no cuam tshuam nrog HPMC molecules los tsim cov gel lossis cov qauv network muaj zog dua, ua rau cov viscosity ntawm cov tshuaj ntxiv. Piv txwv li, xanthan gum yog ib qho polysaccharide ntuj nrog cov nyhuv thickening muaj zog. Thaum siv nrog HPMC, ob qho tuaj yeem tsim cov nyhuv synergistic thiab ua rau cov viscosity ntawm lub cev ntau ntxiv.
6. Hloov qib ntawm kev hloov pauv ntawm HPMC
Qhov viscosity ntawm HPMC kuj muaj feem cuam tshuam nrog qib ntawm kev hloov pauv ntawm nws cov methoxy thiab hydroxypropoxy pawg. Qib ntawm kev hloov pauv cuam tshuam rau nws cov solubility thiab viscosity ntawm cov tshuaj. Los ntawm kev xaiv HPMC nrog ntau qib ntawm kev hloov pauv, qhov viscosity ntawm cov tshuaj tuaj yeem hloov kho. Yog tias xav tau viscosity siab dua HPMC, cov khoom uas muaj cov ntsiab lus methoxy siab dua tuaj yeem xaiv tau, vim tias cov ntsiab lus methoxy siab dua, qhov muaj zog dua hydrophobicity ntawm HPMC, thiab viscosity tom qab yaj yog qhov siab dua.
7. Ntev lub sijhawm yaj
Lub sijhawm uas HPMC yaj kuj tseem yuav cuam tshuam rau nws cov viscosity. Yog tias HPMC tsis yaj tag, qhov viscosity ntawm cov tshuaj yuav tsis mus txog qhov zoo tagnrho. Yog li ntawd, kev ncua sijhawm yaj ntawm HPMC hauv dej kom zoo kom ntseeg tau tias HPMC tau hydrated tag nrho tuaj yeem ua rau kom muaj viscosity ntawm nws cov tshuaj. Tshwj xeeb tshaj yog thaum yaj ntawm qhov kub qis, cov txheej txheem yaj HPMC yuav qeeb, thiab kev ncua sijhawm yog qhov tseem ceeb.
8. Hloov cov xwm txheej ntawm kev txiav
Qhov viscosity ntawm HPMC kuj muaj feem cuam tshuam nrog lub zog shear uas nws raug thaum siv. Nyob rau hauv cov xwm txheej shear siab, qhov viscosity ntawm HPMC kua yuav txo qis ib ntus, tab sis thaum shear nres, qhov viscosity yuav rov qab los. Rau cov txheej txheem uas xav tau viscosity ntau dua, lub zog shear uas cov kua raug raug tuaj yeem txo qis, lossis nws tuaj yeem ua haujlwm nyob rau hauv cov xwm txheej shear qis kom tswj tau viscosity siab dua.
9. Xaiv qhov hnyav molecular kom raug
Qhov hnyav molecular ntawm HPMC ncaj qha cuam tshuam rau nws qhov viscosity. HPMC nrog qhov hnyav molecular loj dua tsim cov qauv network loj dua hauv cov tshuaj, ua rau muaj viscosity siab dua. Yog tias koj xav tau nce qhov viscosity ntawm HPMC, koj tuaj yeem xaiv cov khoom HPMC nrog qhov hnyav molecular siab dua. Txawm hais tias HPMC 15 cps yog cov khoom lag luam qis-viscosity, qhov viscosity tuaj yeem nce ntxiv los ntawm kev xaiv cov khoom sib txawv siab-molecular-weight ntawm tib yam khoom.
10. Xav txog tej yam uas cuam tshuam rau ib puag ncig
Tej yam ib puag ncig xws li av noo thiab siab kuj tseem yuav muaj qee yam cuam tshuam rau qhov viscosity ntawm HPMC kua. Hauv qhov chaw muaj av noo siab, HPMC tuaj yeem nqus cov dej noo los ntawm huab cua, ua rau nws cov viscosity txo qis. Txhawm rau kom tsis txhob muaj qhov no, cov xwm txheej ib puag ncig ntawm qhov chaw tsim khoom lossis siv tuaj yeem tswj tau kom zoo kom qhov chaw qhuav thiab ntawm qhov siab tsim nyog los tswj qhov viscosity ntawm HPMC kua.
Muaj ntau txoj hauv kev los ua kom cov viscosity ntawm HPMC 15 cps kua, suav nrog kev nce concentration, tswj qhov kub, kho pH, siv cov khoom pab thickening, xaiv qib tsim nyog ntawm kev hloov pauv thiab qhov hnyav molecular, thiab lwm yam. Txoj kev tshwj xeeb uas yuav tsum tau xaiv nyob ntawm qhov xwm txheej ntawm daim ntawv thov tiag tiag thiab cov txheej txheem xav tau. Hauv kev ua haujlwm tiag tiag, nws feem ntau tsim nyog los xav txog ntau yam thiab ua qhov kev hloov kho thiab kev ua kom zoo dua kom ntseeg tau tias qhov kev ua tau zoo tshaj plaws ntawm HPMC kua hauv cov ntawv thov tshwj xeeb.
Lub sijhawm tshaj tawm: Lub Kaum Hli-16-2024