Benzimidazole 2-vinyl-1-oxide

Whereas UL 94 delivers only a classification based on a pass-and-fail system, LOI can be used to rank and compare the flammability behavior of different materials. In Figure 15.2 the increasing LOI values are presented for different polymers as an example POM = poly(oxymethylene), PEO = poly(ethyl oxide), PMMA = poly(methyl methacrylate), PE = polyethylene), PP, ABS, PS, PET = polyethylene terephthalate), PVA = poly(vinyl alcohol), PBT, PA = poly(amide), PC, PPO = poly(phenylene oxide), PSU, PEEK = poly(ether ether ketone), PAEK = poly(aryl ether ketone), PES, PBI = poly(benzimidazole), PEI = poly(ether imide), PVC = poly(vinyl chloride), PBO = poly(aryl ether benzoxazole), PTFE. The higher the LOI, the better is the intrinsic flame retardancy. Apart from rigid PVC, nearly all commodity and technical polymers are flammable. Only a few high-performance polymers are self-extinguishing. Table 15.1 shows an example of how the LOI is used in the development of flame-retarded materials. The flame retardant red phosphorus (Pred) increases... 

Structural studies of polymer surfaces. Materials that have been studied include PMMA [239], PMMA-polypyrrole composites [240], polyfchloromethyl styrene) honnd 1,4,8,11-tetrazacyclotetradecane, polyfchloromethyl styrene) honnd thenoyl triflnoroacetone [241], poly(dimethyl siloxane)-polyamide copolymers [242], PS [243], ion-implanted PE [244], monoazido-terminated polyethylene oxide [245], polynrethanes [246], polyaniline [247], flnorinated polymer films [248], poly(o-tolnidine) [249], polyetherimide and poly benzimidazole [250], polyfnllerene palladinm [251], imidazole-containing imidazolylethyl maleamic acid-octadecyl vinyl ether copolymer [252], polyphenylene vinylene ether [253], thiophene oligomers [254], flnorinated styrene-isoprene derivative of a methyl methacrylate-hydroxyethyl methacrylate copolymer [255], polythiophene [256], dibromoalkane-hexaflnorisopropylidene diphenol and bisphenol A [257], and geopolymers [258]. 

Reddy VP, Kumar V, Rao KR (2010) Copper oxide nanoparticles catalyzed vinylation of imidazoles with vinyl halides under ligand-free conditions. Tet Lett 51 3181-3185 Dandia A, Parewa V, Rathore KS (2012) Synthesis and characterization of CdS and Mn doped CdS nanoparticles and their catalytic application for chemoselective synthesis of benzimidazoles and benzothiazoles in aqueous medium. Catal Comm 28 90-94 Itoh T, Nagata K, Ishikawa H, Ohsawa A (2004) Synthesis of 2-arylbenzothiazoles and imidazoles using scandium triflate as a catalyst for both a ring closing and an oxidation steps. Heterocycles 63 2769-2783... 

A very mild copper-catalyzed vinylation of amines, which involved the use of advantageous vinyl boronic acids at room temperature, was developed by Lam (Scheme 21) [89]. They proved that a combination of Cu(OAc)2 and pyridine A-oxide was an efficient catalyst system for the coupling of tra/w-1-hexenyl boronic acid with certain amines. In this respect, not only A-heterocycles such as benzimidazole and indazole but also numerous ureas and lactams underwent the cross-coupling under similar conditions. 

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