Speaker
Mr
Johan Larsson
(Lund University)
Description
The increasing demand for environmentally friendly surfactants has resulted in a comprehensive research to identify surfactants that are biodegradable, non-toxic and produced from sustainable raw materials. In this respect, alkylglycosides with one or more sugar molecules, have shown not only promising surface properties but also favourable characteristics regarding sustainability, especially those with an oligomeric head group. However, the self-assembly and interfacial behaviour of oligomeric sugar surfactants are not very well understood. The aim with this study is therefore to get a deeper understanding of oligomeric alkylglycoside behaviour at interfaces and in solution in relation to their structure.
The properties of different alkylglycosides, with focus on hexadecyl-β-D-maltopyranoside (C16G2) and a polydisperse mixture with tails of both 16 and 18 carbon atoms and head groups lengths between 1 and 20 glucose molecules (TZ30), have been characterized both in terms of interfacial (tensiometry, ellipsometry) and in bulk behaviour (DLS, SAXS, SANS, cryo-TEM). C16G2 has been found to form long wormlike micelles when dissolved in water above the cmc. The size of these micelles are relatively unaffected of temperature changes from 25 °C up to 90 °C and NaCl concentrations up to 1 M, while they are growing slightly with increasing concentration (0.5-10 mM). TZ30 are both forming small spherical micelles and other larger aggregates when dissolved in water at concentrations above the cmc. Ellipsometry measurements have shown that both C16G2 and TZ30 adsorbs at a hydrophobised silica surface to a higher extent than PEG-surfactants of comparable size.
Primary author
Mr
Johan Larsson
(Lund University)
Co-authors
Prof.
Marie Wahlgren
(Lund University)
Prof.
Patrick Adlercreutz
(Lund University)
Prof.
Stefan Ulvenlund
(Lund University)
Prof.
Tommy Nylander
(Lund University)
