Novel Fluorinated Oligo-Surfactants Imparted by the Aggregation of Fluoroalkyl Segments

Abstract

Fluoroalkanoyl peroxide was found useful for the synthesis of fluoroalkyl end-capped oligomers having COOH, SO₃H, O=C-NR₁R₂, OH, betaine segments, phosphorous segments and blocked-isocyanato segments. The fluoroalkyl end-capped oligomers were generally soluble not only in water but common organic solvents as well. These oligomers were highly surface active, showing very low surface tensions and clear break points, as in the case of low molecular weight fluorinated surfactants. Self-organization thus occurs to form molecular aggregates. Based on light scattering studies, fluoroalkyl end-capped oligomers having COOH formed ellipsoidal micelles. Fluoroalkyl end-capped oligomers with hydroxy or betaine segments gave rise to gelation owing to hydrophobic interaction of end-capped fluoroalkyl segments in addition to the hydrogen bonding and/or the ionic interaction of betaine segments.
Moreover, as some examples of interesting properties of fluoroalkyl end-capped acrylamide type oligomers, the unique binding power of Ca²⁺ or Cr³⁺, selective recognition of organic color material having -NH₂ or -NMe₂ groups such as methylene blue and/or luminol, and the immobilization of cytochrome c are discussed. These features may be due to molecular aggregates produced by the interaction between end-capped fluoroalkyls.