Amphiphilic Properties of Hydrotropes Derived from Isosorbide: Endo/Exo Isomeric Effects and Temperature Dependence

Abstract

The hydrotropic properties of short-chain monoalkyl ethers of isosorbide have been studied with emphasis on the difference between the two regioisomers (2-O- and 5-O-monoalkylisosorbide, C(i)Iso-exo and C(i)Iso-endo, respectively). On the one hand, the partitioning in a water/cyclohexane system has been measured, and on the other hand, the "optimal formulation" of C(i)Iso/oil/water systems has been determined by changing the oil polarity. In both cases, whatever the alkyl chain length (four or five carbons), C(i)Iso-exo appears to be less hydrophilic due to an intramolecular hydrogen bond that makes the free hydroxyl group less available. With one substituted position, the hydrophilicity contribution of isosorbide is slightly higher than the one of two ethylene glycols when the exo hydroxyl remains free, whereas it is closer to one ethylene glycol when this hydroxyl is substituted. With regard to the sensitivity to temperature, the hydrophilicity loss on heating seems to be similar for both isomers and close to what is obtained for poly(ethylene glycol) derivatives if we consider the evolution of the partition coefficients. In C(i)Iso-endo/oil/water systems, however, the variation of the optimal oil with temperature tends to show that the isosorbide derivatives are approximately 2 times less sensitive than their poly(ethylene glycol) counterparts to temperature changes.

Unsaturated polyester resins for thermoset applications using renewable isosorbide as a component for property improvement

“…The results show that longer reaction times (60296 h) needed to account for lower reactivity of the endohydroxyl on the isosorbide due to sterics. 26,27 This extended reaction time was necessary to achieve higher molecular weight prepolymers which also resulted in greater conversion to the fumarate ester.…”

“…On the other hand, the endo hydroxyl on the isosorbide fused ring system has been shown to undergo intramolecular hydrogen bonding in addition to being protected by the steric bulk of the rest of the molecule. 26 Thus, the simple addition of the steric hindrance from the secondary alcohols 5 likely retards the reaction. Thus, these combined factors necessitate a significant increase in the amount of time needed to facilitate the formation of larger molecular weight oligomers.…”

Experimental Investigation and Modeling of the Performance of Pure and Mixed Surfactant Inhibitors: Partitioning and Distribution in Water-Oil Environments

“…The cell is a glass cylinder, one inch in diameter, which has two ports (top and bottom) for the sampling of oil and aqueous phase separately without contamination from each other. The cell was kept in a water bath at the desired temperatures (25,40,50, and 60…”

Selective Syntheses and Properties of Anionic Surfactants Derived from Isosorbide

“…Scheme shows the different reactivity based on the geometry of the two hydroxy groups. The hydroxy group of C2 appears to be in the exo orientation, whereas that of C5 appears to be in the endo orientation, because of the fused tetrahydrofuran (THF) cycles (Abenhaïm et al, ; Claffey et al, ; Kumar and Ramachandran, ; Zhu et al, ). The reaction shown in Scheme is used to prepare many compounds such as isosorbide nitrates (used to treat cardiac or vascular disease) and alkyl derivatives (used as solvents in pharmaceutical and cosmetic compositions) (Durand et al, ; Fenouillot et al, ; Lavergne et al, ).…”