Imidazole-containing copolymers

Fig. 18 Reaction rate of hydrolysis of p-nitrophenyl acetate as a function of inverse temperature. Thermosensitive imidazole-containing copolymers (PVCL-Vim, PNIPA-Vim), 1-methylimidazole and poly(l-vinylimidazole) act as catalysts. Numbers in the copolymer abbreviations denote the Vim content (in mole percent). Vim 1-vinylimidazole. (Adapted from Ref. [18])...

The vinylphenol unit was similaily introduced to imidazole-containing copolymers cf. Section 4-4), but the incorporation resulted only in the increase of hydro-phobicity of the polymer catalyst On the other hand, some rate enhancements were observed due to phenolic compounds bound onto Bl-VP copolymers, and cooperative catalysis for die intraoanplex reactirxi was implied (71). 

Catalysis by Imidazole-containing Copolymers of Enhanced Hydrophobic Properties... 

Li M, Feng S, Fang S, Xiao X, Li X, Zhou X, Lin Y (2007) Quasi-solid state dye-sensitized solar cells based on p3uidine or imidazole containing copolymer chemically crosslinked gel... 

Separations with imidazole-containing copolymers have been used for the purification of proteins containing natural metal-ion binding sites and His-tag recombinant proteins, which bind to the metal immobilised onto the metal chelating group (Galaev et al, 1997 Kumar et al, 2003 Mattiasson c/ 7,2007). 

Imidazole-containing polymers and copolymers have been obtained from a variety of derivatized imidazoles, including the unsubstituted 1-, 2- and 4(5)-vinylimidazole monomers. Primary interest in these polymers has centered around metal complexation, ion exchange and catalytic properties. 

Fig. 19 Distribution functions of the hydrodynamic diameter for the imidazole-containing thermosensitive copolymers in 2-propanol-water solutions at various temperatures a PNIPA-Vim, 11% of imidazole b PVCL-Vim, 29% of imidazole. (Adapted from Ref. [18])...

The functions of polymers formed from disubstituted acetylenes have also been studied extensively (Chart 3.6). Kwak et al. found that poly(diphenylacetylene) derivative 21 showed strong blue-green emission. Hsu and coworkers fabricated an LED composed of ITO/PEDOT/ diphenylacetylene copolymer 22/Ca/Al and observed very high device performance with a maximum luminescence of 4230 cd/m at 14 V and a maximum current efficiency of 3.37 cd/A at 7 Imidazole-containing polymer 23 can be prepared from a chlorine-bearing polymer. The fluorescence of 23 is quenched by a trace amount of Cu , but not when also... 

Given that poly(l-vinylimidazole) (PVIm) has a pATa of around 5.5, this polymer does not complex DNA at physiological pH. Thus, Allen et al. quatemized the imidazole ring with various substituents such as bromoethanol in order to obtain permanently charged imidazolium-containing copolymers [107]. As the quatemization degree was increased, fewer sites were available for protonation,... 

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]. 

This review article summarizes our more recent investigations of the esterolytic action of water soluble imidazole containing polymers. In our previous work we have explained increased reactivity of polymeric reactants in terms of electrostatic and cooperative effects. Recently, we have directed our efforts in emphasizing the apolar interaction as it has reflected dramatic rate enhancements and proven a predominant factor in determining the maximum catalytic efficiency. Polymeric catalysts which are included in this review are poly[l-alkyl-4(5)-vinyl-imidazoles] and their copolymers, hydro-phobic terpolymers of 4(5)-vinylimidazole, copoly[vinylamine/4(5)-vinylimidazole], and poly(ethylenimine-g L-histidine). All of these catalysts share the common property of water solubility and the capability of attaining high catalytic efficiencies which is attributed to apolar interactions. 

The hydrolysis of copolymers containing vinyl imidazole (Vim) as the third component, poly(MAOT-co-AA-co-VIm) (No. 15), poly(AOT-co-AA-co-VIm) (No. 13), and poly(MAOA-co-AA-co-VIm) (No. 17), is shown in Fig. 3. These copoly-... 

In other investigations by the author [2,3] additional positive resists compositions were prepared containing either imidazole, (11), or tertiary amine derivatives, (III), respectively, and then blended with the select copolymer, (IV), as illustrated. 

Catalysis by Copolymers Containing Imidazole and Other Secondary... 

The acylation rate (ka) did not differ mudi between die terpolymer (PHA-MIm-AAm) and a copolymer which contains only die hydroxamate functional group (PHA-AAm, 7). In contrast, die hydrolysis of the acelyl hydroxamate intermediate was greatly accelerated by the assistance of the intrapolymeric imidazole group (60—80 fold increase in kj). 

The possibility of the ccmcerted catah c action in the solvolysis of PNPA was investigated for copolymers containing mercaptan and imidazole functions 29(111). 

Heme (7 a) with a triblock copolymer containing styrene and 1-vinyl imidazole is teversiUy, slowly oxidized. ... 

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