A Zwitterionic Polymerizable Surfactant from ω-Hydroxyltetradecanoic Acid Provides Stimuli-Responsive Behavior

Abstract

ω-Hydroxytetradecanoic acid (ω-HOC14), prepared via an efficient yeast-catalyzed ω-hydroxylation of the corresponding fatty acid, was converted in two steps to the polymerizable zwitteronic surfactant ω-O-maleate-α-2-dimethyl­aminoethyl tetradecanamide (DMTA). Emulsion polymerizations of styrene with DMTA, bearing carboxylic and tertiary amine groups at the ω- and α-positions, were conducted in different pH environments. Emulsion polymerizations were most successful (particle diameters <80 nm, high styrene conversion) under basic conditions (pH 9.8 and 11.0), where latex samples have highly negative zeta potentials (−40.4 to −46.0 mV). Because of the zwitterionic nature of the surfactant, transparent or semitransparent latexes were obtained under either acidic (pH < 4) or basic (pH > 9) conditions. In the pH range of 4–9, aggregation occurred; however, by adjustment of the pH to either acidic or basic conditions, partial redispersion occurred highlighting DMTA’s ability to provide stimuli-responsive colloidal behavior. Unexpectedly, upon drying the latex formed at pH = 3.1, a membrane with nanodimension pores was formed.

Fundamentals and applications of zwitterionic antifouling polymers

“…Apart from antifoulingrelated applications, the unique structures and chemistries of zwitterionic materials also offer other properties and functions for other application, e.g. ionic liquid for polyelectrolyte systems [6,7], drug/gene delivery system with supreme cell uptake efficiency and nontoxicity [8], and smart materials with pH-, solvent-, thermal-responsive property [9][10][11]. As a generally-accepted water barrier principle, the antifouling property of zwitterionic polymers fundamentally originates from a tightly and stably bounded water layer near zwitterionic polymers via strong electrostatically induced hydration [12].…”

Geometry transformation of ionic surfactants and adsorption behavior on water/n-decane-interface: calculation by molecular dynamics simulation and DFT study

“… 5 Moreover, adjusting pH value could obtain both cationic and anionic surfactant due to the structural feature of amide based ionic surfactants. 6 However, investigation of the structural effect on interfacial properties of amide based ionic surfactants on water/ n -decane interface is limited. Especially, research about interpretation the weak interactions between the ionic surfactants, oil phase and water molecules at a quantum level is extremely limited.…”