Halides monomers

Thiazyl halide monomers undergo a variety of reactions that can be classified under the general headings (a) reactions involving the 7i-system of the N = S triple bond, (b) nucleophilic substitution, (c) halide abstraction, and (d) halide addition. The cycloaddition of NSF with hexafluoro-1,3-butadiene provides an example of a type (a) reaction. 

Photoionization and Photoelectron Spectroscopy of Alkali Halide Monomers, Dimers, and Trimers... 

Comparison of Calculated and Experimental Splitting Patterns of Alkali Halide Monomers (in eV)... 

This manuscript summarizes the most significant current experimental information regarding the photoionization behavior of alkali halide monomers, dimers and trimers. Some data exist on higher ionization potentials, (30) and ionic model calculations have also been applied to these higher levels. (19, 30)... 

We now briefly discuss the deflection patterns to be expected when alkali halide monomers and dimers pass between the polefaces of an inhomogeneous electric field (a detailed analysis of the deflection pattern due to molecules possessing strong electric dipole moments will be presented elsewhere). The geometry of the experiment is shown in Figure 1. 

Various synthetic approaches have been demonstrated for the synthesis of PAEs since early days [35 0], PAEs were synthesized by Ullmann condensation between bisphenols and aryl fcis-halide monomers using Cu(I) salt/pyridine as catalyst [36], General Electric developed the first commercially successful PAE poly(2,6-dimethyl phenylene oxide) (PPO) [38], It was prepared by oxidative coupling of 2,6-dimethyI phenol. However, this process has its own restrictions, because it does not allow much structural variation or inclusion of any electron-withdrawing group into the polymer main chain. First attempts to synthesize polysulfones (PSF) were successfully done by Friedel-Crafts sulfonylation reaction of arylenedisulfonyl chlorides, for example, diphenyl ether-4,4 -disulfonyl chloride with diaryl ethers, for example, diphenyl ether, or by self-condensation of 4-phenoxy benzene sulfonyl chloride in the presence of FeCls [41], Whereas the former reaction involves side reactions (sulfonylation not only in the para- but also in the ort/io-position), the latter produces only the desired linear all-para products. 

Hunter and Yohe laid out the first mechanism of carbocationic polymerization in 1933 (13). According to their proposal, the metal halide-monomer interaction leads to the formation of a zwitterion (the German word zwitter stands for between ) ... 

The water pools of the (w/o) microemulsions mediate reactions, and in this work dilute the higher halides and precipitate the halide monomers in the water pools. High amount of water at a constant surfactant concentration, however, compromises the stability of the (w/o) microemulsions [44], Furthermore, at high-water content, the surfactant protective layer becomes less rigid [29], This, in turn, promotes the role of intermicellar nucleation and growth and increases the probabiUty of nanoparticle aggregation. 

At present, many sulfonated derivatives of polymers such as poly(ether ether ketone), polysulfone, poly (ary lene ether snlfone), poly(styrene), and polyCphenylene sulfide) have been developed for fnel cells [10-14], More recently, the synthesis of sulfonated poly(arylene ether snlfone) and/or snlfonated poly(arylene ether ketone)s copolymers by direct copolymerization of biphenol, disnlfonated-activated aromatic halide monomers, and the precnrsor—activated aromatic halide monomer for fnel cell membrane applications— were carried ont [12,15],... 

Somewhat to our surprise, we have been unable to find reference to any published attempt to calculate these bond energies of the gaseous dihalides on the basis of the Bom-Lande lattice energy model. We have therefore carried out such calculations at a level that reproduced the bond energies of the alkali metal halide monomers with an average deviation from the experimental values of 8%. All calculations were carried out on linear XMX structures. The ratio between these calculated values and their experimental counterparts are listed in the last column of Table 2. 

The homocoupling of all yl-aryl halide monomers was carried out by Trumbo, D. L. Marvel, C. S. J. Polym. ScL, Polym. Chem. Ed. 1986,24,2311. The alkynyl cross-coupling reaction conditions employed were developed by Takahashi, S. Kurqyama, Y. Sonogashira, K Hagihara, N. Synthesis 1980,627. 

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