Synthesis and application of polyzwitterionic and polyampholytic maleic acid-alt-(diallylamino)propylphosphonates

Abstract

Ammonium persulfate-initiated alternate copolymerization of maleic acid with phosphonate ester monomer [(CH2CH–CH2)2NH+(CH2)3PO3Et2Cl−] gave polyzwitterion A which upon ester hydrolysis afforded antiscalant polyampholyte B.

A sorbent containing pH-responsive chelating residues of aspartic and maleic acids for mitigation of toxic metal ions, cationic, and anionic dyes

“…1b). The succinic acid motifs have two ionizable CO 2 H groups having expected pK a of 2.6 and 5.8, 18 while the pK a values of 2.5 and 4.5 could be assigned to the two CO 2 H groups in the residues of aspartic acid residue. 25,26 In the pH range 6-7.25 used in the current study, the majority of CO 2 H groups is expected to be anionic CO 2 À which can impart electrostatic attraction to entrap cationic MB (Scheme 3).…”

“…Under the reaction conditions, neither diallyamine salts nor maleic acid can undergo homopolymerization; the polymerization invariably leads to the formation of alternate addition of diallylamine salt and maleic acid. 18 The high IEC value of 7.65 mmol g À1 was attributed to CAPE 8 having four CO 2…”

“…16,17 Copolymerization of maleic acid (MA) with diallylammonium salts having reactivity ratios of almost zero gives alternate copolymers. 18 Copolymerization precludes the formation of individual homopolymers because of the zero reactivity ratios. To synthesize the cross-linked alternate copolymer, cross-linker 4 was synthesized in excellent yield as outlined in Scheme 1.…”

“…Herein, we would like to synthesize a new resin and examine its efficacy in the removal of Pb(II), cationic dye MB, and anionic dye Eriochrome Black T (EBT) from aqueous systems. For this purpose, adsorbent cross-linked polyzwitterionic acid (CPZA) 7 has been synthesized for the rst time using cyclopolymerization protocol [16][17][18] involving inexpensive cross-linker 4, N,N-diallylaspartic acid hydrochloride (5) bearing the skeleton of aspartic acid [H 3 N + CH(CH 2 CO 2 H) 2 CO 2 À ], and maleic acid (MA) 6 (Schemes 1 and 2). The current pH-responsive resin 7, loaded with four CO 2 H and chelating motifs of NH + /CO 2 À in each repeating unit, offers the latitude for effective mitigation of cationic as well as anionic materials.…”

Synthesis of stimuli‐responsive ionic cyclopolymers in search of phosphorous‐free antiscalants

“…Judicious choice of the substituents (R 1 , R 2 ) in the DAA salts has led to the incorporation of anionic, zwitterionic (±) and ampholytic (+ −) charges on the pH‐responsive polymer backbone 7,8 . Copolymerization of DAA salts with sulfur dioxide 9 or maleic acid (MA) 10,11 invariably leads to alternate copolymers as a result of each monomeric pairs having reactivity ratios of zeros (i.e., r 1 ≈ 0, r 2 ≈ 0) 10 …”