Taw qhia
Hauv kev lag luam xws li zaub mov, tshuaj pleev ib ce, thiab tshuaj, emulsifiers yog cov khoom xyaw tseem ceeb. Lawv tuaj yeem sib xyaw cov roj thiab dej tsis sib xws los ua homogeneous emulsions. Txawm li cas los xij, ntsib nrog ntau yam ntawm emulsifiers, peb tuaj yeem xaiv qhov tsim nyog tshaj plaws li cas? Qhov no coj peb mus rau lub tswv yim tseem ceeb hauv kev tshawb fawb emulsion-HLB value(Hydrophilic{0}}Lipophilic Balance). Kab lus no yuav muab cov lus qhia meej rau lub ntsiab lus, qhov tseem ceeb, thiab lub luag haujlwm tseem ceeb ntawm HLB tus nqi hauv cov ntawv thov emulsifier.
HLB Value yog dab tsi?
HLB stands for "Hydrophilic{0}}Lipophilic Balance." Nws yog tus lej muaj nuj nqis uas ntsuas qhov txheeb ze lub zog ntawm hydrophilic (dej-hlub) thiab lipophilic (roj-hlub) pab pawg hauv cov emulsifier molecule. Lub tswvyim ntawm HLB yog thawj zaug los ntawm Griffin hauv 1949 thiab feem ntau yog los ntawm0 rau 20.
- HLB (0-6): Qhia tias muaj zog lipophilicity, yooj yim soluble hauv roj, haum rau kev npajdej-hauv- roj (W/O)emulsions, qhov twg dej yog dispersed nyob rau hauv roj.
- Medium HLB (7-9): Qhia cov khoom ntub dej, feem ntau siv los ua cov tshuaj ntub dej.
- HLB (8-18): Qhia tias muaj zog hydrophilicity, yooj yim soluble hauv dej, haum rau kev npajroj-hauv- dej (O/W)emulsions, qhov twg roj yog dispersed nyob rau hauv dej.
- Very high HLB (>18): Feem ntau yog siv los ua cov tshuaj solubilizers los muab cov tshuaj insoluble rau hauv dej.
The Importance of HLB Value in Emulsifiers
HLB tus nqi yog cov lus qhia tseem ceeb rau kev xaiv emulsifier thiab daim ntawv thov, thiab nws qhov tseem ceeb yog xav txog hauv cov hauv qab no:
1. Precise Matching ntawm Emulsion Hom
Cov khoom sib txawv xav tau ntau hom emulsion. Piv txwv li, mis nyuj thiab daim tawv nqaij cream feem ntau yog roj - hauv - dej, thaum butter thiab cov tshuaj pleev ib ce yog dej - hauv - roj. Los ntawm HLB tus nqi, cov qauv tsim tuaj yeem tshuaj xyuas cov emulsifiers sai sai rau cov hom phiaj emulsion, zam qhov tsis pom kev sim.
2. Optimizing Emulsification Efficiency
Txhua theem roj muaj nws "hloov tus nqi HLB." Tsuas yog thaum lub HLB ntawm lub emulsifier phim qhov yuav tsum tau HLB ntawm cov roj theem tuaj yeem tsim qhov ruaj khov thiab zoo emulsion. Kev sib txuam tsis raug tuaj yeem ua rau theem sib cais, demulsification, lossis ntxhib ntxhib ntxhib.
3. Taw qhia Emulsifier Blending
Hauv kev xyaum, ib qho emulsifier feem ntau tsis tuaj yeem ua tau raws li txhua qhov kev xav tau ib txhij. Los ntawm kev suav cov HLB tus nqi ntawm cov khoom sib xyaw emulsifiers (qhov hnyav nruab nrab), ob lossis ntau dua emulsifiers tuaj yeem sib xyaw kom ua tiav lub hom phiaj HLB, yog li tau txais cov txiaj ntsig zoo. Piv txwv li, kev sib xyaw siab -HLB thiab qis-HLB emulsifiers hauv kev faib ua feem tso cai rau kev tswj hwm ntawm emulsion stability.
4. Predicting Emulsifier Cwj Pwm
HLB tus nqi kuj tseem pab kwv yees qhov kev ua tau zoo ntawm emulsifiers hauv cov tshuab sib txawv, xws li solubility, dispersibility, thiab stability, muab lub hauv paus theoretical rau kev hloov kho.
Yuav txiav txim thiab siv HLB tus nqi li cas?
1. Determination of HLB Value
HLB tus nqi tuaj yeem txiav txim siab sim, xws li los ntawm kev sib piv emulsion lossis cloud point method, los yog tau los ntawm kev xam cov theoretical. Rau nonionic surfactants, empirical qauv tuaj yeem kwv yees HLB. Piv txwv li, rau polyol fatty acid esters, HLB=20 × (1 - S/A), qhov twg S yog tus nqi saponification ntawm ester, thiab A yog tus nqi acid ntawm fatty acid.
2. Cov kauj ruam rau kev xaiv emulsifier
- Txiav txim siab HLB ntawm cov roj theem: Sib tham txog cov ntaub ntawv los yog kev sim kom pom HLB ntau yam uas xav tau los tsim cov emulsion ruaj khov nrog rau theem roj lub hom phiaj.
- Xaiv cov emulsifiers: Xaiv ib qho emulsifier nrog HLB ze rau tus nqi uas yuav tsum tau muaj, lossis muab ntau yam emulsifiers kom ua tiav lub hom phiaj.
- Txheeb xyuas qhov ruaj khov: Ua emulsification thwmsim los soj ntsuam cov tee me me, theem sib cais, kub / txias tsis kam, thiab lwm yam, kom paub meej tias qhov ua tau ntawm cov emulsifier formulation.
Examples of HLB Values for Common Emulsifiers
| Lub npe Emulsifier | HLB Value | Daim ntawv thov tseem ceeb |
|---|---|---|
| Span 85 | 1.8 | W/O emulsifier |
| Span 80 | 4.3 | W/O emulsifier |
| Span 60 | 4.7 | W/O emulsifier |
| Kev 85 | 11.0 | O / W emulsifier |
| Twee 80 | 15.0 | O / W emulsifier |
| Thib 20 | 16.7 | O / W emulsifier |
| Sodium lauryl sulfate (SDS) | 40 | Anionic emulsifier / solubilizer |
Xaus
Raws li lub tswv yim tseem ceeb hauv kev tshawb fawb emulsifier, HLB tus nqi muab cov cuab yeej yooj yim tab sis muaj zog rau kev tsim qauv. Nws pab cov tsim qauv txav los ntawm kev sim ua pov thawj pom tseeb- thiab - yuam kev rau kev kwv yees, txhim kho kev ua tau zoo thiab kev ua tiav ntawm cov khoom tsim khoom. Txawm hais tias nyob rau hauv cov khoom noj emulsion, cov khoom siv tawv nqaij, lossis cov chaw muag tshuaj, kev nkag siab thiab siv HLB tus nqi yog ib kauj ruam tseem ceeb rau kev ua tiav ruaj khov, siab - cov khoom zoo. Nrog kev txhim kho txuas ntxiv ntawm emulsification thev naus laus zis, daim ntawv thov ntawm HLB tus nqi yuav txuas ntxiv mus ntxiv, paving txoj hauv kev rau cov khoom lag luam tshiab.
