Premium
Changes in Phase Behavior from the Substitution of Ethylene Oxide with Carbon Dioxide in the Head Group of Nonionic Surfactants
Author(s) -
Spiering Vivian J.,
Ciapetti Aurora,
Lima Michelle Tupinamba,
Hayward Dominic W.,
Noirez Laurence,
Appavou MarieSousai,
Schomäcker Reinhard,
Gradzielski Michael
Publication year - 2020
Publication title -
chemsuschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.412
H-Index - 157
eISSN - 1864-564X
pISSN - 1864-5631
DOI - 10.1002/cssc.201902855
Subject(s) - ethylene oxide , chemical engineering , oxide , chemistry , petrochemical , liquid crystal , rheology , materials science , organic chemistry , copolymer , composite material , optoelectronics , engineering , polymer
Nonionic ethylene oxide (EO)‐based surfactants are widely employed in commercial applications and normally form gel‐like liquid crystalline phases at higher concentrations, rendering their handling under such conditions difficult. By incorporating CO 2 units in their hydrophilic head groups, the consumption of the petrochemical EO was reduced, and the tendency to form liquid crystals was suppressed completely. This surprising behavior was characterized by rheology and studied with respect to its structural origin by means of small‐angle neutron scattering (SANS). These experiments showed a strongly reduced repulsive interaction between the micellar aggregates, attributed to a reduced hydration and enhanced interpenetration of the head groups owing to the presence of the CO 2 units. In addition, with increasing CO 2 content the surfactants became more efficient and effective with respect to their surface activity. These findings are important because the renewable resource CO 2 is used, and the CO 2 ‐containing surfactants allow handling at very high concentrations, an aspect of enormous practical importance.