Thermal Studies of New Lead(II) Coated‐Wire Membrane Electrodes

AbstractFive plastic membrane Pb2+‐selective electrodes were prepared based on 1,4‐bis(N‐tosyl‐o‐aminophenoxy)butane I, 1,4‐bis(N‐allyl‐N‐tosyl‐o‐aminophenoxy)butane II, 1,4‐bis(N‐benzyl‐N‐tosyl‐o‐aminophenoxy)butane III, 1,4‐bis[N‐(o‐allyloxybenzyl)‐N‐tosyl‐o‐aminophenoxy]butane IV, and 1,4‐bis(N‐octyl‐N‐tosyl‐o‐aminophenoxy)butane V as neutral carriers. The electrodes exhibited nearly Nernstian responses over the concentration ranges, 2.5×10−4–4.0×10−2, 2.5×10−5–4.0×10−2, 7.9×10−5–4.0×10−2, 2.2×10−5–4.0×10−2, and 1.9×10−4–4.0×10−2 M for electrodes composed with the ionophores I–V, respectively. All electrodes showed pH range of about 4.0 to 11.5 and working temperature range of 22 to 70 °C with isothermal temperature coefficients of 1.19×10−3, 1.16×10−3, 1.16×10−3, 1.00×10−3 , and 1.32×10−3 V/°C for electrodes I–V respectively.