RESUMEN
For the development of selective and sensitive chemical sensors, we have developed a new family of poly(ether-phosphoramide) polymers. These polymers were obtained with satisfactory yields by nucleophilic aromatic polycondensation using isosorbide as green resources, and bisphenol A with two novel difluoro phosphinothioic amide monomers. Unprecedented, the thiophosphorylated aminoheterocycles monomers, functionalized with two heterocyclic amine, N-methylpiperazine and morpholine were successfully obtained by nucleophilic substitution reaction of P(S)-Cl compound. The resulting polymers were characterized by different analytical techniques (NMR, MALDI-ToF MS, GPC, DSC, and ATG). The resulting partially green polymers, having tertiary phosphine sulfide with P-N side chain functionalities along the main chain of polymers are the sensitive film at the surface of a gold electrode for the impedimetric detection of Cd, Ni, Pb and Hg. The bio-based poly(ether-phosphoramide) functionalized with N-methylpiperazine modified sensor showed better analytical performance than petrochemical based polymers for the detection of Ni2+. A detection limit of 50 pM was obtained which is very low compared to the previously published electrochemical sensors for nickel detection.
Asunto(s)
Técnicas Biosensibles , Níquel , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Electrodos , Éter , Éteres , Límite de Detección , Níquel/química , Fosforamidas , Polímeros/química , SulfurosRESUMEN
Three phosphate esters 1â»3 were successfully synthesized from the reaction of 2-, 3- and 4-hydroxybenzaldehyde with phosphoryl chloride. Reactions of 1â»3 with benzidine in the presence of glacial acetic acid gave the corresponding novel phosphorus organic polymers 4â»6 containing the azomethane linkage. The structures of the synthesized compounds were confirmed by Fourier transform infrared spectroscopy, nuclear magnetic resonance and elemental analysis. Interesting physiochemical properties for the polymeric materials 4â»6 were observed using a combination of several techniques such as gel permeation chromatography, scanning electron microscopy, Brunauerâ»Emmettâ»Teller and nitrogen adsorptionâ»desorption isotherm, Barrettâ»Joynerâ»Halenda and H-sorb 2600 analyzer. The mesoporous polymers 4â»6 exhibit tunable porosity with Brunauerâ»Emmettâ»Teller surface area (SABET = 24.8â»30 m²·gâ»1), pore volume (0.03â»0.05 cm³·gâ»1) and narrow pore size distribution, in which the average pore size was 2.4â»2.8 nm. Polymers 4â»6 were found to have high gas storage capacity and physico-chemical stability, particularly at a high pressure. At 323 K and 50 bars, polymers 4â»6 have remarkable carbon dioxide uptake (up to 82.1 cm³·gâ»1) and a low hydrogen uptake (up to 7.4 cm³·gâ»1). The adsorption capacity of gasses for polymer 5 was found to be higher than those for polymers 4 and 6.