Interfacial Interaction between Cellulose Derivatives and Surfactants at Solid Surfaces. An Ellipsometry Study

Abstract

The effect of surfactants on the adsorption properties of ethyl(hydroxyethyl)cellulose (EHEC) and its hydrophobically modified analogue (HM-EHEC) at the solid−liquid interface has been studied by ellipsometry. The adsorption characteristics of EHEC and HM-EHEC without the presence of surfactants are also presented. The polar silica surface and a hydrophobized silica surface were used as substrates. On the polar silica surface, a small addition of the anionic surfactant sodium dodecyl sulfate (SDS) caused a 3- to 5-fold expansion of the preadsorbed EHEC or HM-EHEC layers, while the adsorbed amount was less influenced. On the hydrophobized silica surface, SDS could replace EHEC (>10 mM SDS), while some adsorbed HM-EHEC still could be detected well above the critical micelle concentration of SDS in the bulk (14 mM). The nonionic surfactant octa(ethylene oxide) dodecyl ether (C12E8) did not affect the adsorbed layer structure on silica, and the cationic surfactant cetyltriammonium chloride (CTAC) on hydrophobized silica showed similar effects as SDS but with a smaller magnitude. It is proposed that the adsorbed layer structure mainly is governed by polymer−surfactant interfacial interactions.

Temperature-dependent adsorption of cellulose ethers on silica and hydrophobized silica immersed in aqueous polymer solution

“…Several cellulose ethers share the same behaviour and find use in many applications due to their adsorption properties and due to the fact that their temperature response can be modified by small changes in the degree of substitution. Examples include ethyl(hydroxyethyl)cellulose (EHEC), [5][6][7][8][9][10][11][12][13][14] methylcellulose (MC) [15][16] and hydroxypropylmethylcellulose (HPMC). 17 MC has been used to enhance drug release from microcrystals, 15 and functionalized by laminin it has been utilized in neural tissue engineering.…”

“…[22][23] The inhibition of intermolecular association, due to hydroxypropyl groups, has also been indicated by NMR data. 21 The effect of temperature on adsorption and layer structure has been investigated for some thermo-responsive polymers, including poly(N-isopropylacrylamide) and EHEC, using techniques such as quartz crystal microbalance measurements, 2,27-30 ellipsometry 9,3 and surface force techniques. 8,[11][12]14 In earlier studies, the conformation of EHEC on hydrophobized mica was shown to be relatively flat, and the main driving force for the adsorption was suggested to be hydrophobic interactions.…”

From surfactant to cellulose and DNA self-assembly. A 50-year journey

“…Methodological developments by Bengt Jönsson, Mikael Landgren and Tommy Nylander laid the ground for the Ph D theses of Martin Malmsten (see, for example, references [ 148 , 149 ]) and Fredrik Tiberg (see below), focussing on polymer and surfactant adsorption, respectively. Much of the later work concerned mixed polymer–surfactant systems, with a thesis by Fredrik Joabsson (for example, see reference [ 150 ]) on mixed systems of non-ionic cellulose derivatives and ionic surfactants and much work by Tommy Nylander and students and coworkers on polyelectrolyte-surfactant systems (Yulia Samoshina, Eiji Terada, Marité Cárdenas etc.).…”

Bi-layer formation of imidazole-modified ethyl(hydroxyethyl)cellulose at a hydrophobic surface as monitored by QCM-D

“…Because of the high viscosity and shear thinning properties of solutions of this polymer, these formulations are easy to stir and does not drip [1]. EHEC has been used for research purposes extensively the last 15 years, and its surface characteristics have been studied rigorously [2][3][4][5][6][7][8][9][10]. By chemically cross-linking EHEC large changes in physically properties are obtained [11,12].…”