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Abstract Copper ions in wastewater present substantial environmental hazards, toxic to aquatic species and prone to bioaccumulation. Addressing this, we present a novel cross‐linked polythiourethane (C‐PTU) as a promising chelating adsorbent for the effective removal of copper ions from wastewater. A new monomer, 5‐(2,2,2‐trifluoroacetamide) benzene‐1,3‐bis(carbonyl) isothiocyanate (TFA‐ITC), was synthesized and further condensed with a 1,4‐butane diol to produce a trifluoroacetamide functionalized polythiourethane (TFA‐PTU) and subsequently generating amine functionalized polythiourethane (A‐PTU). The cross‐linking reaction was carried out through amino groups present on the polymer backbone with terephthaloyl chloride, resulting in the formation of C‐PTU. The monomer and polymers underwent characterization using Fourier transform infrared,1H, and13C nuclear magnetic resonance spectroscopy, with X‐ray diffraction analyzing the resin's chain alignment. Thermogravimetric and differential scanning calorimetry assessed C‐PTU's thermal properties. The adsorption process for Cu(II) ions was studied using atomic absorption spectroscopy, optimizing conditions for maximal uptake. Results revealed that C‐PTU exhibited a significant adsorption capacity for Cu(II) ions, reaching 67% after a 2 h contact time, with optimal adsorption occurring at pH 6. The Langmuir adsorption isotherm described the sorption mechanism, indicating favorable monolayer cation adsorption via coordination with donor sites on C‐PTU. This research presents a viable solution for copper ion contamination in wastewater, illustrating C‐PTU as an efficient, environmentally friendly adsorbent, marking progress toward cleaner water resources.
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Synthesis and characterization of modular polyphosphonate homopolymers and copolymers
Abstract Linear polyphosphonates with the generic formula –[P(Ph)(X)OR′O]n– (X = S or Se) have been synthesized by polycondensations of P(Ph)(NEt2)2and a diol (HOR′OH = 1,4‐cyclohexanedimethanol, 1,4‐benzenedimethanol, tetraethylene glycol, or 1,12‐dodecanediol) followed by reaction with a chalcogen. Random copolymers have been synthesized by polycondensations of P(Ph)(NEt2)2and mixture of two of the diols in a 2:1:1 mol ratio followed by reaction with a chalcogen. Block copolymers with the generic formula –[P(Ph)(X)OR′O](x + 2)–[P(Ph)(X)OR′O](x + 3)– (X = S or Se) have been synthesized by the polycondensations of Et2N[P(Ph)(X)OR′O](x + 2)P(Ph)NEt2oligomers with HOR′O[P(Ph)(X)OR′O](x + 3)H oligomers followed by reaction with a chalcogen. The Et2N[P(Ph)(X)OR′O](x + 2)P(Ph)NEt2oligomers are prepared by the reaction of an excess of P(Ph)(NEt2)2with a diol while the HOR′O[P(Ph)(X)OR′O](x + 3)H oligomers are prepared by the reaction of P(Ph)(NEt2)2with an excess of the diol. In each case the excess, x is the same and determines the average block sizes. All of the polymers were characterized using1H,13C{1H}, and31P{1H} NMR spectroscopy, TGA, DSC, and SEC.31P{1H} NMR spectroscopy demonstrates that the random and block copolymers have the expected arrangements of monomers and, in the case of block copolymers, verifies the block sizes. All polymers are thermally stable up to ~300°C, and the arrangements of monomers in the copolymers (block vs. random) affect their degradation temperatures andTgprofiles. The polymers have weight average MWs of up to 3.8 × 104 Da.
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- Award ID(s):
- 1632881
- PAR ID:
- 10451014
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Polymer Science
- Volume:
- 58
- Issue:
- 13
- ISSN:
- 2642-4150
- Page Range / eLocation ID:
- p. 1825-1842
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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