The investigation primarily focuses on synthesizing Polyvinyl Chloride (PVC)-coordination polymer (CP) polymeric membranes that employ L-Cu-NO₃ (¹_∞[Cu₃L₂(NO₃)]NO₃·2MeOH·2H₂O based on the Schiff base H₂L, where H₂L stands for N,N’-bis[(2-hydroxybenzilideneamino)-propyl]-piperazine)) as a coordination polymer. The membrane’s capacity to hold moisture is greatly improved by the addition of CPs. The water contact angle dropped from 73.4° for the PVC to about 71° for the composite membrane, indicating that the CP–PVC polymer interactions improved the hydrophilicity. Impedance spectroscopy (EIS) was used to determine the membranes response to the tested concentrations of phenol solution at pH 9.11 in the concentration range of 10⁻¹⁰ to 10⁻² mol·L⁻¹. A PVC membrane with a 0.6 wt% L-Cu-NO₃ deposit on a Cu electrode yields the best response. Between 10⁻⁸ and 10⁻⁵ mol·L⁻¹ phenol, a linear dependence was found. The detection limit was 4.64 × 10⁻⁸ mol·L⁻¹.

The corrosion inhibitory performance of a coordination polymer, ¹_∞[Cu₃L¹₂(NO₃)](NO₃)·2H₂O and a complex compound, [Zn₂L²(CH₃COO)₂]·2H₂O, toward iron corrosion in a saline medium at pH 2.5 was investigated. Here, L¹ and L² stand for N,N’-bis[(2-hydroxybenzylideneamino)-propyl]-piperazine and N,N’-bis[(3-methoxysalicylideneamino)-propyl]-piperazine, respectively. This study was motivated by the recognized potential of organic compounds incorporating N, S, and O heteroatoms and π-conjugated electronic systems as effective corrosion inhibitors. The evaluation of the performance is determined using electrochemical impedance spectroscopy (EIS) and potentiometric methods (CP). The experimental findings reveal that an optimal inhibitor concentration of 100 ppm ensures enhanced corrosion protection. For both inhibitors, the corrosion rate decreased by two orders of magnitude compared with the untreated iron sample.