Synthesis and Surface Properties Characterization of Perfluoroalkylated Oligo(oxyethylene)glycols

Abstract

A series of perfluoroalkylated oligo(oxyethylene) glycols as non-ionic fluorinated surfactants was prepared. The synthesis was performed by adding a molecule of a oligo(oxyethylene)glycol of the general formula HO(CH 2 CH 2 O) n OH (n = 1, 2, 4, 6.4, 22.3) to 2-(perfluorooctylmethyl) oxirane in the presence of catalytic amounts of a Lewis acid. This procedure led to the formation of an amphiphilic molecule characterized by an hydrophobic lipophobic perfluorinated tail and hydrophilic non-ionic oligo(oxyethylene)chain. Infra red spectroscopy, mass spectroscopy and multinuclear NMR spectroscopy allowed the chemical characterization of the synthesized compounds to be made. Critical micellar concentration, surface tension, interfacial tension and cloud point measurements carries out on aqueous solutions allowed us to evaluate the surface and interfacial properties of the perfluoroalkylated oligo(oxyethylene)glycols. In addition, surface pressure-area (p, A) diagrams allowed us to determine the principal parameters characterizing the state of their monolayers. The aim of the work was to investigate the effect of the hydrophilic chain length on physical and surface properties.

Preparation of Epoxy Resin Emulsifiers with Different Structures and a Comparative Study of their Properties

“…According to Figure 10, the surface tension of epoxy resin emulsifiers decreases significantly with increasing emulsifier concentration and levels off when the concentration reaches CMC. This is a common phenomenon followed by emulsifiers or surfactants in general [53–55] . The CMC values for each of the epoxy resin emulsifiers with different structures are therefore calculated and included in Table 3.…”

“…This a common phenomenon followed by emulsifiers or surfactants in general. [53][54][55] The CMC values for each of the epoxy resin emulsifiers with different structures are therefore calculated and included in Table 3.…”