Highly water dilutable microemulsions : a structural study

• Highly aqueous dilutable microemulsions based on biocompatible materials were developed and structurally investigated. Phase diagrams were constructed for systems consisting of non-ionic Tweens (20, 40 and blends of them), R-(+)-limonene, ethanol, water and propylene glycol. The obtained phase diagrams reveal the formation of fully aqueous dilutable microemulsions along certain dilution lines in the surfactant-rich region. Two phase transitions of the investigated systems were detected by conductivity measurements, from w/o to bicontinuous and to the o/w, without phase separation. Interfacial properties and the dynamic structure of the surfactant’s monolayer were studied by electron paramagnetic resonance spectroscopy. It was observed that the mobility of the spin probe and the rigidity of the membrane are affected by increasing aqueous content and by the type of surfactant. DLS measurements were performed in (o/w) microemulsions for different aqueous content, and oil droplet diameters in the range of 8.2 to 17.4 nm were observed.

Subject headings

NATURVETENSKAP  -- Kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences (hsv//eng)

Keyword

biocompatible microemulsions

limonene

tweens

epr

dls

electrical conductivity

Chemistry

Kemi

Publication and Content Type

vet (subject category)

ovr (subject category)