Reduction of dissolved oxygen in boiler water using new redox polymers

Abstract

New polymers were used as catalysts for the removal of dissolved oxygen in boiler water. These polymers, based upon hydroquinone-quinone redox system, were prepared by polymerization of methyl 4-(2,5-dimethoxybenzyl)cinnamate and copolymerization of this monomer with 4-(4 0 -vinylphenethyl)-1,10-phenanthroline. The resulting product was used to synthesize polymers containing transition metal ions. Nuclear magnetic resonance, infrared spectroscopy, and elemental analysis were achieved to characterize monomers and/or electron-transfer polymers. These polymers were used for the removal of oxygen from water. It was shown that the oxygen content was reduced to less than 0.1 mg L À1 in $ 70 s. Based on the obtained results, the redox capacity of two polymers were determined. It was established that the poly-4-(2,5-dihydroxybenzyl)cinnamic acid reached a redox capacity of 69.7 mg of O 2 per gram of polymer.

Phenanthroline—A Versatile Ligand for Advanced Functional Polymeric Materials

“…For instance, due to the complexation of transition metals by phen, palladium or nickel catalyzed reactions were excluded, limiting C‐C coupling reactions . Yet, 4‐methyl‐1,10‐phenanthroline proved to be a convenient starting compound for the synthesis of both acrylate‐ and styrene‐based phen‐monomers (Scheme ) . For the synthesis of the acrylate‐based monomer, 4‐methyl‐1,10‐phenanthroline was selectively lithiated at the methyl group and subsequent salt metathesis with (3‐bromopropoxy)‐ tert ‐butyldimethylsilane formed the silyl ether protected alcohol.…”

“…The corresponding Phen‐styrene monomer (Phen‐styrene, 3 ) was synthesized in a similar procedure. In a salt metathesis reaction between the lithiated 4‐methyl‐phenanthroline and chloro‐methylstyrene (CMS), the styrene‐based phenanthroline derivative 4‐(4‐vinylphenethyl)‐1,10‐phenanthroline ( 3 ) was generated …”

“…[23,24] Yet, 4-methyl-1,10-phenanthroline provedt ob eaconvenients tarting compound for the synthesis of both acrylate-and styrene-based phen-monomers (Scheme 1). [25] For the synthesis of the acrylate-based monomer,4 -methyl-1,10-phenanthroline was selectively lithiated at the methyl group and subsequents alt metathesis with (3-bromopropoxy)-tert-butyldimethylsilane formed the silyl ether protected alcohol. After deprotection with tetra-n-butylammonium fluoride (TBAF), an esterification reactionb etween the resulting phen-butanol (1)a nd acryloyl chloride resulted in the acrylatesubstituted phenanthrolined erivative 4-(1,10-phenanthrolin-4yl) butyl acrylate in high yields, herein termedP hen-acrylate (2).…”

“…In as alt metathesis reaction between the lithiated 4-methyl-phenanthroline and chloro-methylstyrene( CMS), the styrene-based phenanthroline derivative4 -(4-vinylphenethyl)-1,10-phenanthroline( 3)w as generated. [25] Polymerization Techniques-Polar SystemA Monomers, which are commonly employed in the synthesis of polar polymers, are often based on acrylates or acrylamides. [26][27][28] For the synthesis of the polar phen-functionalized polymer system A, N,N-dimethylacrylamide (DMAA) was used as ac o-monomer.T he suitability of DMAA in RDRP polymerization procedures has already been demonstrated.…”