One-pot synthesis of zinc ion coordinated hydroxy-terminated polyurethanes based on low molecular weight polyethylene glycol and toluene diisocyanate

Present work reports the synthesis of polyethylene glycol, PEG 300 (soft segment) and toluene 2,4-diisocyanate, TDI (hard segment) based hydroxy-terminated polyurethane ligands (HTPU₃₀₀) for the formulation of metal ion coordinated polymeric systems. The effect of zinc ions within HTPU₃₀₀ [Zn(II)HTPU₃₀₀] was evaluated by studying the thermal, and antibacterial properties of the polymeric material along with their conductivity and crystalline properties. Zn(II)HTPU₃₀₀ was conveniently synthesized in appreciable yields by following a facile one-pot addition polymerization reaction. The detailed thermal stability of Zn(II)HTPU₃₀₀ was evaluated using TGA and DSC analysis combined with IPDT calculations. FTIR technique was used to ascertain the structure of Zn(II)HTPU₃₀₀, while SEM/EDX and XRD techniques were used to study their morphology and elemental analysis of the material. Further, the in-vitro antimicrobial activity of the HTPU₃₀₀ and Zn(II)HTPU₃₀₀ was investigated against gram-positive (Staphylococcus aureus and Bacillus subtilis) and gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacterial strains. The comparatively moderate efficacy against bacterial strain supports the possible application of such HTPU₃₀₀ as thermally stable bacterial resistant additive material in polymeric or other structural constructions.