Sulfonated styrenic block copolymers

Sulfonated Styrenic Block Copolymers Two kinds of styrene-based membranes were introduced by Dais Analytic Corporation (see Fig. 29.10). The first was fabricated from a commercially available styrene-ethylene-butylene-styrene triblock polymer (Kraton) by postsulfonation of the styrenic units (Ehrenberg et al., 1995). Later, a new Dais Analytic membrane was developed based on an ethylene-styrene pseudorandom interpolymer from Dow Chemical Corporation (Serpico et al., 2002). Using a... 

Weiss et al. [75] have synthesized Na and Zn salt of sulfonated styrene(ethylene-co-butylene)-styrene triblock ionomer. The starting material is a hydrogenated triblock copolymer of styrene and butadiene with a rubber mid-block and PS end-blocks. After hydrogenation, the mid-block is converted to a random copolymer of ethylene and butylene. Ethyl sulfonate is used to sulfonate the block copolymer in 1,2-dichloroethane solution at 50°C using the procedure developed by Makowski et al. [76]. The sulfonic acid form of the functionalized polymer is recovered by steam stripping. The neutralization reaction is carried out in toluene-methanol solution using the appropriate metal hydroxide or acetate. 

Shi, Z. Q., and Holdcroft, S. 2005. Synthesis and proton conductivity of partially sulfonated poly([vinylidene difluoride-co-hexafluoropropylene]-b-styrene) block copolymers. Macromolecules 38 4193-4201. 

Sulfonation is very useful chemical modification of polymer, as it induces high polarity in the polymer changing its chemical as well as physical properties. Sulfonated polymers are also important precursors for ionomer formation [75]. There are reports of sulfonation of ethylene-propylene diene terpolymer (EPDM) [76, 77], polyarylene-ether-sulfone [78], polyaromatic ether ketone [79], polyether ether ketone (PEEK) [80], styrene-ethylene-butylene-styrene block copolymer, (SEBS) [81]. Poly [bis(3-methyl phenoxy) phosphozene] [82], Sulfonated polymers show a distinct peak at 1176 cm"1 due to stretching vibration of 0=S=0 in the -S03H group. Another peak appears at 881 cm 1 due to stretching vibration of S-OH bond. However, the position of different vibrational bands due to sulfonation depends on the nature of the cations as well as types of solvents [75, 76]. 

Synthesis of the poly(sodium styrene sulfonate)-/7-polymethyl methacrylate-II-polymethyl Methacrylate-/ -poly(sodium styrene sulfonate) (Plla) block copolymer... 

Mauritz, K. A., Blackwell, R. L, and Beyer, F. L., Viscoelastic properties and morphology of sulfonated poly(styrene-i -ethylene/butylenes-i>-styrene) block copolymers (sBCP), and sBCP/[silicate] nanostructured materials. Polymer, 45, 3001-3016 (2004). 

Slyrene-ethylene/butylene-styrene block copolymer Poly (styrene-co-allyl alcohol). See Styrene/allyl alcohol copolymer Poly (styrene-co-butadiene). See Styrene/butadiene polymer Poly (styrene-co-maleic anhydride). See Styrene/MA copolymer Polystyrene latex Polystyrene resin. See Polystyrene Polystyrene, sulfonated. See Sodium polystyrene sulfonate... 

Styrene-ethylene/butylene-styrene block copolymer 66197-78-2 Nonoxynol-9 phosphate 66455-14-9 C12-13 pareth-7 lmbentln-C/123/065 66455-15-0 CIO-12 pareth-3 CIO-12 pareth-6 CIO-12 pareth-8 Sulfonic L12-3... 

Polytetramethylene ether glycol diamine Polyurethane, thermoplastic Polyvinyl butyral Pyridine Ricinoleic acid Sodium o olefin sulfonate Styrene-ethylene/butylene-styrene block copolymer Styrene/MA copolymer Sucrose octaacetate Tall oil glycerides... 

Several sulfonated block copolymers such as SSEBS (sulfonated poly (styrene-b-ethylene-co-butylene-b-styrene)) block copolymer (Wang et al. 2007), ABA-Triblock copolymer (Imaizumi et al. 2012), sulfonated pentablock ABCBA copolymers (Gao et al. 2012), and sulfonated pentablock ionomer (PBI)-based... 

Vaterite is thermodynamically most unstable in the three crystal structures. Vaterite, however, is expected to be used in various purposes, because it has some features such as high specific surface area, high solubility, high dispersion, and small specific gravity compared with the other two crystal systems. Spherical vaterite crystals have already been reported in the presence of divalent cations [33], a surfactant [bis(2-ethylhexyl)sodium sulfate (AOT)] [32], poly(styrene-sulfonate) [34], poly(vinylalcohol) [13], and double-hydrophilic block copolymers [31]. The control of the particle size of spherical vaterite should be important for application as pigments, fillers and dentifrice. 

Styrenic-siloxane block and graft copolymers, Tg dependence on architecture and molecular weight, 95,95/ Styrenic-siloxane block copolymers, 86 Substrate catalyst ratio, chloromethylation, 18 Sulfonation, instability of sulfonated PPO, improvement, 6 Surface grafting... 

There have been few synthetic reports employing these monomers beyond the Ballard work, most likely as a result of presumed high cost and monomer availability. However, the performance and stability demonstrated by these materials in fuel cells may spur further developments in this area. The above-reported copolymers are believed to be random systems both in the chemical composition of the copolymer backbone and with regard to sulfonic acid attachment. Novel methods have been developed for the controlled polymerization of styrene-based monomers to form block copolymers. If one could create block systems with trifluorostyrene monomers, new morphologies and PEM properties with adequate stability in fuel cell systems might be possible, but the mechanical behavior would need to be demonstrated. 

As an extension of the previous work, copolymers based on partially sulfonated ethylene—styrene pseudorandom interpolymers have also been employed instead of the block copolymers (Figure Due to the unique nature of the polymerization catalyst, styrene residues are separated by at least one ethylene residue and the acid groups are distributed randomly along the chain. This material provides an economical and unique counterpoint to the sulfonated SEES PEMs, where the sulfonic acid groups are bunched together in the styrene blocks. Controlling the styrene content in each material provides a route to control the level of sulfonation and resultant ion exchange capacity of the PEM. 

Miyaki and Fujimoto and co-workers [16,17] have obtained an even finer distribution of fixed charge groups by casting films from multicomponent block copolymers such as poly(isoprene- >-styrene- >-butadiene- >-(4-vinyl benzyl)dime-thylamine- Msoprene). These films show a very regular domain structure with a 200-500 A spacing. After casting the polymer film, the (4-vinyl benzyl) dimethy-lamine blocks were quatemarized with methyl iodide vapor, and the styrene blocks were sulfonated with chlorosulfuric acid. 

Mixed anionic (sulfonated - carboxylated) ionomers [81] were prepared by sulfonation of maleated block-copoly (styrene/ethylene-butylene/styrene) (m-SEBS) by acetyl sulfate, followed by neutralisation of the sulfonated maleated product, leading to the formation of a new block copolymer ionomer based on both carboxylate and sulfonate anions according to Scheme 4.6. FT-IR spectra confirm the presence of both carboxylated and sulfonate ions (Figure 4.9). 

Th-FFF can be applied to almost all kinds of synthetic polymers, like polystyrene, polyolefins, polybutadiene, poly(methyl methacrylate), polyisoprene, polysulfone, polycarbonate, nitrocelluloses and even block copolymers [114,194,220]. For some polymers like polyolefins, with a small thermal diffusion coefficient, high temperature Th-FFF has to be applied [221]. Similarly, hydrophilic polymers in water are rarely characterized by Th-FFF, due to the lack of a significant thermal diffusion (exceptions so far poly(ethylene oxide), poly(vi-nyl pyrrolidone) and poly(styrene sulfonate)) [222]. Thus Th-FFF has evolved as a technique for separating synthetic polymers in organic solvents [194]. More recently, both aqueous and non-aqueous particle suspensions, along with mixtures of polymers and particles, have been shown to be separable [215]. 

Using the same method Storey et al. prepared ionic star—block copolymers.55-58 Styrene was oligomerized followed by the polymerization of butadiene. The living diblock copolymer was subsequently linked with methyltrichlorosilane to provide a three-arm star—block copolymer of styrene and butadiene. Hydrogenation of the diene blocks and sulfonation of the styrene blocks produced the desired ionic star-block structure having ionic outer blocks and hydro-phobic inner blocks, as depicted in Scheme 13. 

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