Polymerizable electrolytes

On the oOier hand, a major problem encountered in inverse emulsion polymerization is the formation of coagulum in the course of the reaction, due either to rapid autoacceleration or poor colloidal stability. The coagulum forma-ti i is more severe vrith water-soluble initiators at low concentraticus and at temperatures above 50 C [2,23]. The incoixxnation of additives such as electrolytes (sodium sulfate, 2-5 wt% based on the aqueous phase) can in some cases decrease flie amount of coagulum by a factor of five or more [12,14]. When polymerizable electrolytes (sodium acrylate, methaciyloyloxyethyltrimetbylam-moniiim chloride) are copolymerized with acrylamide, they have the same action... 

The electrolyte, AN-100, is an aqueous solution of a polymerizable unsaturated resin partially neutralized with triethylamine. Synthesis of the polymer and the electrolyte are described below. 

The acylation of alcohol-containing monomers, e.g. hydroxyethyl acrylates or vinyl benzyl alcohol with maleic, succinic or sulfosuccinic anhydride leads to bifunctional polymerizable surfactants. A range of such products has been synthesized and tested in batch polymerization and core-shell polymerization of styrene and butyl acrylate [26]. In both cases good stability, high conversion and little burying of the Surfmers were observed. Water rebound was also limited. These advantageous features were however offset by an unacceptable resistance to electrolytes and to freeze-thaw. 

The development of transparent polymer electrolyte membrane from the bi-continuous-microemulsion polymerization of 4-vinylbenzene sulfonic acid Hthium salt (VBSIi), acrylonitrile and a polymerizable non-ionic surfactant, co-methoxypoly(ethylene oxide)4o-undecyl-a-methacrylate (Ci-PEO-Cn-MA-40) was reported in 1999 [94,95]. The ionic conductivities of the polymer electro-... 

Also reported for comparison are the curves relative to two non polymerizable salts, sodium acetate and sodium chloride which cause a salting out of the surfactant. The role of electrolytes in the stabilization of the polymerized systems will be discussed below. The cloud point shift values, for the surfactant blend, measured after addition of a unimolal electrolyte solution are listed in Table II. 

These salting-out effects are partly responsible for the high HLBopt values found experimentally (see Figure 1). At a given temperature, the HLB of the blend is made more lipophilic on addition of an electrolyte monomer. The HLBopt has to be shifted to higher values in order to counterbalance the solubility decrease in water. Thus, the HLBopt measured is an apparent value, the effective one being that obtained in the absence of electrolyte. Figure 5 shows the increase in the HLBopt value observed when the ionic monomer content in an acrylamide-sodium acrylate feed stock increases from 0 to 65% (11). Vhen the monomer used is not an electrolyte (acrylamide), a similar curve is obtained by addition of a non polymerizable salt such as sodium acetate. 

Similarly, electrolytes play a major role in the stability of the final latices. Polymerization of AH microemulsions in the absence of salt gives unstable latices, even at high surfactant concentrations. When salts with high salting-out efficiency (sodium acetate) are added to the systems, stable and clear microlatices are produced. Polymerization of microemulsions containing a polymerizable salt leads, under appropriate conditions, to the formation of stable microlatices (11,29). 

These results clearly show that the nost effective polymerizable microemulsions for industrial applications (minimum amount of surfactant) are bicontinuous. It is interesting to note that addition of salting-in-type electrolytes (inducing no W I - W III transition) to AM microemulsions gives unstable and turbid latices. 

Dendrimers containing polymerizable groups can be electrodeposited onto suitable electrode surfaces (Pt or ITO) either by controlled potential electrolysis or by repeated cycling between the appropriate anodic and cathodic potential limits. The amount of electroactive material electrodeposited can be controlled with the electrolysis time or number of scans [86,107], Enzymes or other biomolecules can be dissolved in the electrolyte of appropriate pH and the biocatalytic role of the dendrimer can be studied. 

Diblock polyoxyethylene-polyoxypropylene styrenic macromonomers, with the polymerizable group at the end of the hydrophobic part have been prepared and used in styrene emulsion polymerization [34]. Latexes of high stability towards added electrolyte have been obtained. However the HLB was not well-optimized so that a high amount of coagulum was formed (Surfmer XI). 

Besides the above-described polymerizable monomer additives, snlfnr-based componnds were proposed in our group as additives for forming anode SEI, inclnding butyl sultone (BS) [82, 83], propane sultone (PS) [84, 85], prop-l-ene-l,3-sulton (PES) [86], as well as ES [54,87], These sulfur family additives have higher reduction potentials than the electrolyte solvents, as shown in Fig. 5.29. 

The later methods, proposed by Motorola [159, 170] and Mitsubishi Electric [171] researchers, differ in implementation details, but they share a common feature in that a separate adhesive layer (PVdF) is applied to the separator and used to bond the electrode and the separator films, using in the first case the hot, liquid electrolyte as an in situ PVdF plasticizer. Sony [172, 173] researchers described the use of thin, liquid electrolyte-plasticized polyacrylonitrile layer directly applied either to the electrode or the separator surfaces as an effective ion-conductive adhesive. Sanyo [174,175] investigators, on the other hand, used thermally polymerizable additives to gel, or solidify, liquid electrolyte solutions in a wound, packaged battery. 

Many IL synthesized have a polymerizable double bound, so as a second way of action, we planned to polymerize these molecules, in order to obtain electrolytes polymers type. These... 

The acylation of alcohol-containing monomers, such as hydroxyethyl acrylates and methacrylates or vinylbenzyl alcohol, with maleic, or succinic, or sulfosuccinic anhydride, allows easy preparation of bifunctional polymerizable surfactants [64]. Some among these compounds, listed in Table 5, have been engaged in batch polymerization of styrene as well as in core-shell copolymerization of styrene and butyl acrylate. Stable latexes have been obtained in both cases, with only low floe production. A high conversion of the surfmers was most often reached, with little burying. However, these latexes do not show a noticeable resistance to the addition of electrolytes and cannot withstand freezing tests these features are not so surprising because their stabilization is only electrostatic and in no way steric. It can be noted, however, that their water rebound is somewhat limited, unless their water... 

The products were polymers of methyl methacrylate, butyl acrylate, or their copolymer. The amount of surfactant was about 9% of the monomers and for the cosurfactant the feature was only 1 %. When the same surfactant was used with pentanol as cosurfactant or with no cosurfactant, the particle size distribution was much broader, even bimodal. The latexes were shown to be stable vs. electrolyte (aluminum sulfate), and also for several freeze-thaw cycles. These features were attributed more to the nature of the surfactant than to the use of polymerizable cosurfactant. 

The introduction of polymerizable groups into the ionic liquid structure has been presented as a very interesting way to obtain good ionic conductivity without liquid components. These polymerized ionic hquids (PlLs) have been developed for battery electrolyte and for other solid electrolyte apphcations.0iang et al., 2006 Ohno et al., 2004 Washiro et al., 2004 Winther-Jensen et al., 2009)... 

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