Hyperbranched polymer surfactant: synthesis, characterization and surface tension activity

A series of hyperbranched polymer surfactants (HBP-C8, HBP-C12 and HBP-C16) were synthesized by the reaction between hydroxyl-terminated hyperbranched polymers (HBP) and fatty acyl chloride. The structure of obtained hyperbranched polymer surfactant was characterized by FTIR, NMR and GPC. The results showed that the products have amphiphilic structure. The thermal property of the hyperbranched polymer surfactant investigated by DSC and TGA was strongly influenced by the length of end alkyl chain. Surface activity of hyperbranched polymer surfactant was analyzed by surface tension method and UV spectrophotometry, respectively. The results showed that hyperbranched polymer surfactant took on better surface activity, which can effectively reduce the surface tension of the water. The hyperbranched polymer surfactant has a lower critical micelle concentration (CMC) and displays single molecular micellar properties, which can package small hydrophilic molecules in relatively low concentration. Graphical abstract

Ionic Liquid-Based Surfactants: Recent Advances in Their Syntheses, Solution Properties, and Applications

The impetus for the expanding interest in ionic liquids (ILs) is their favorable properties and important applications. Ionic liquid-based surfactants (ILBSs) carry long-chain hydrophobic tails. Two or more molecules of ILBSs can be joined by covalent bonds leading, e.g., to gemini compounds (GILBSs). This review article focuses on aspects of the chemistry and applications of ILBSs and GILBSs, especially in the last ten years. Data on their adsorption at the interface and micelle formation are relevant for the applications of these surfactants. Therefore, we collected data for 152 ILBSs and 11 biamphiphilic compounds. The head ions of ILBSs are usually heterocyclic (imidazolium, pyridinium, pyrrolidinium, etc.). Most of these head-ions are also present in the reported 53 GILBSs. Where possible, we correlate the adsorption/micellar properties of the surfactants with their molecular structures, in particular, the number of carbon atoms present in the hydrocarbon “tail”. The use of ILBSs as templates for the fabrication of mesoporous nanoparticles enables better control of particle porosity and size, hence increasing their usefulness. ILs and ILBSs form thermodynamically stable water/oil and oil/water microemulsions. These were employed as templates for (radical) polymerization reactions, where the monomer is the “oil” component. The formed polymer nanoparticles can be further stabilized against aggregation by using a functionalized ILBS that is co-polymerized with the monomers. In addition to updating the literature on the subject, we hope that this review highlights the versatility and hence the potential applications of these classes of surfactants in several fields, including synthesis, catalysis, polymers, decontamination, and drug delivery.

Efficiency of single and mixed dimeric surfactants micelles on solubil-ization of polycyclic aromatic hydrocarbons

The solubilization of polycyclic aromatic hydrocarbons (PAHs) such as naphthalene, phenanthrene and pyrene by single and mixed anionic dimeric surfactants was investigated and correlated with micellar properties of these surfactants. The surface and micellar properties of single and binary mixed combinations of anionic dimeric surfactants have been studied through surface tension as well as conductivity measurements at 300 K. The associations between their micelle properties and solubilizing efficiency towards PAHs have been quantified and discussed in terms of the molar solubilization ratio (MSR), micelle-water partition coefficient (Km) and standard free energy of solubilization (ΔG0S).The negative value of ΔG0Sexhibits spontaneously the solubilization process. The MSR values increase with the order “pyrene < phenanthrene < naphthalene”. The current study provides significant information for the selection of mixed dimeric surfactants for solubilizing water-insoluble compounds.