Anionic fluorinated surfactants

Surfactants used as lubricants are added to polymer resins to improve the flow characteristics of the plastic during processing they also stabilise the cells of polyurethane foams during the foaming process. Surfactants are either nonionic (e.g. fatty amides and alcohols), cationic, anionic (dominating class e.g. alkylbenzene sulfonates), zwitterionic, hetero-element or polymeric (e.g. EO-PO block copolymers). Fluorinated anionic surfactants or super surfactants enable a variety of surfaces normally regarded as difficult to wet. These include PE and PP any product required to wet the surface of these polymers will benefit from inclusion of fluorosurfactants. Surfactants are frequently multicomponent formulations, based on petro- or oleochemicals. 

At the end of the 1990s statistics show that the non-ionic surfactants achieved the highest growth in production rates world-wide, though anionic surfactants (anionics) maintained the dominant position in the surfactant market. Today they are produced in a larger variety by the petrochemical industry than all other types of surfactants. Their production spectrum covers alkyl sulfates (ASs), secondary alkane sulfonates (SASs) and aryl sulfonates and carboxylates via derivatives of partly fluorinated or perfluorinated alkyl surfactants to compounds with an alkylpolyglycolether substructure combined with an anionic moiety such as alkylether sulfates (AESs), phosphates, phosphonates or carboxylates. 

Partly fluorinated or perfluorinated sulfonic and carboxylic acids are compounds with excellent surface activity combined with an extreme stability against chemical or physico-chemical attacks as also described for non-ionic fluorine containing surfactant compounds. The anionic surfactants are shown with their structural formulae in Fig. 2.11.24(1)—(III). A selected ESI-FIA-MS(-) spectrum of a partly fluorinated surfactant (CF3-(CF2)4-(CH2)8-S03H, m/z 461) is presented in Fig. 2.11.25. The FIA spectrum also contains ions of the by-products CF3-(CF2)2-(CH2)8-S03H (m/z 361) and CF3-(CF2)3-(CH2)8-S03H (m/z 411). 

Fluorinated phosphinic and phosphonic acid derivatives Perfluoro derivatives of alkyl phosphonic acid CnF2n+1-P(0)(0H)2 and alkyl phosphinic acid CnF2n+i(CmF2m+1)-P(0)0H (n = m or n m) shown with their general structural formulae in Fig. 2.11.29(1) and (II) were examined by negative ESI- and APCI-FIA-MS. These anionic surfactant compounds contained perfluoro alkyl chains [2,22,25]. By analogy with their behaviour in the TSI-FIA-MS(—) process [25], the phosphonic acid formed [M — H] ions at m/z 399 and 499... 

Linear alkylbenzenes are made from linear terminal olefins and benzene and are important precursors of biodegradable anionic surfactants (LAS, linear alkylbenzenesulfonates). The conventional catalyst is HF, first to be replaced by a fluorinated silica-alumina in the DETAL process. The DETAL process is safer than the HF process and also more cost-effective because no special metallurgy is required and no calcium fluoride waste stream exists.52 Zeolites such as Beta may come to the fore here because they display a higher selectivity to the desired 2-phenyl isomers.55... 

Currently, there is concern about the use of ammonium perfluorooctanoate (APFO), also known as C8 , which is necessary for the manufacture of fluorinated plastics and elastomers in water. C8 is a perfluorinated anionic surfactant used as a dispersing agent in the polymerization and copolymerization of many fluoropolymers, including poly(tetrafluoroethylene) (PTFE), poly(vinylidene... 

Baran JR, Terrazas MS, Dams RJ (2009) Fluorinated anionic surfactants and fluoropolymers in well treatment fluids for petroleum recovery. World Appl 2,009,085,899,200,9. 3M Innovative Properties Company, USA... 

Block copolymers 2.45 and 2.46 were prepared by emulsion copolymerization of styrene and methyl methacrylated terthiophenes in the presence of a fluorinated anionic surfactant using K2S2O8 as a... 

The influence of the anion type on the thermal stability of the imidazolium ILs has been studied by Awad et al. [32]. TTiey have demonstrated that for the hexa-fluorophosphate PF, tetrafluoroborate BF , and bis(trifluoromethylsulfonyl)amide [(CF3SOj)JN, increase of 100 C in the degradation temperature was obtained compared to the use of the halide salts (bromide and chloride). For nanoclays modified with imidazolium salts as surfactants, the works reported in the literature demonstrate a large increase of degradation temperature under nitrogen and oxidative atmosphere compared to ammonium-treated MMT. However, despite the intrinsic stability of imidazolium ILs induced by the substitution of halide anions by fluorinated ones, no significant improvement in the thermal stability of the MMT treated by ILs having tetrafluoroborate or hexafluorophosphate anions has been reported. 

Gohy JF, Mores S, Varshney SK, Jerome R (2003) Self-organization of water-soluble complexes of a poly(2-vinylpyridinium)-block-poly(ethylene oxide) diblock with fluorinated anionic surfactants. Macromolecules 36 2579-2581. doi 10.1021/ma025665v... 

Woods et al. [95] have studied the influence of the fluorocarbon-based polymer processing additive (PEA) Dynamar FX 9613/5920A on the surface and optical properties of polyolefin plastomer blown film by means of XPS and SSIMS. The same techniques were used to study the effect of Dynamar FX 9613 on the surface properties of HDPE [96]. Migration of fluorinated processing aids in HDPE film was also studied by XPS and ATR-FTIR [97]. Lens et al. [98] have reported an XPS study of the orientation of molecules of anionic surfactants, such as... 

Figure 8.7 compares experimental values of the surface excess of C14TAB, CigTAB, and C12TAB + NaBr below the cmc, with values calculated from Equation 8.2 assuming diffusion-controlled adsorption. The excellent agreement between the calculated and measured values demonstrates the absence of an activation barrier in this system. The same conclusion was drawn for the fluorinated anionic surfactant sodium bis(lH,lH nonafluoropentyl)-2-sulfosuccinate (di-CF4). A... 

The segregation and phase sequence of semifluorinated cat-anionic surfactant membranes at different excess surface charges was investigated by freeze-fracture transmission electron microscope (FF-TEM), X-ray diffraction (XRD), and NMR. The thermal behavior of the membranes was evaluated by conductivity, rheology, and deuterium NMR ( H NMR). The cat-anionic fluorinated surfactant mixtures can form faceted vesicles and punctured lamellar phase when there is excess surface charge. The cationic and anionic fluorinated surfactants are stiff in the membranes, like phospholipids in the frozen ciystalline or gel phase. ... 

Homogeneous biocatalysis in both fluorous biphasic and supercritical CO systems has been demonstrated [6]. By forming protein-surfactant complexes by hydrophobic ion pairing with a highly fluorinated anionic surfactant cytochrome c can be solubilized in perfluoromethylcyclohexane (PMFC) and in scCO. The secondary structure of the proteins within these ion-paired complexes has been shown to remain intact, and particle size analysis indicated that small aggregates of protein molecules surrounded by surfactant molecules are formed. The presence of the KDP (perfluoropolyether carboxylate surfactants) ion paired with a-chymotrypsin appears to enhance its catal)4ic activity as compared to that of the native enzyme in a fluorous biphasic system. The facile recycling of the a-chymotrypsin-KDP complex in a fluorous biphasic system has been demonstrated with retention of enzyme artivity over four reaction cycles. 

Anionic surfactants—the hydrophobic part is an anion, for example, RfCOO Na, where Rf is a fluorine-containing hydrophobe. 

Ionic surfactants dissociate in water and form a surface-active ion with an oppositely charged counterion. The surface-active ions of anionic surfactants bear a negative charge. Anionic fluorinated surfactants can form water-insoluble ion pairs with cationic species and are usually not compatible with most cationic surfactants. 

Anionic surfactants are the most important class of fluorinated surfactants. Based on the hydrophile stmcture, anionic fluorinated surfactants can be divided into four main categories ... 

A fluorinated sulfonyl chloride can be reacted with an amino acid to give a fluorinated anionic surfactant with a carboxylic group and a sulfonamido linkage... 

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