Synthesis and characterization of metal-mercaptoacetate hybrids and its application towards ring-opening polymerization of ε-caprolactone: a comparative study

The Mn2+ and Mo6+ based metal-mercaptoacetate (metal-MA) hybrids were prepared by a simple acid-base titration method. The prepared metal-MA hybrids were analysed by FT-IR spectroscopy, UV-visible spectroscopy, SEM, particle size analyser (PSA), XRD and EDX. The prepared metal-MA hybrids were investigated to assess their catalytic activity for ring-opening polymerization (ROP) of epsilon-caprolactone (CL) in the absence of an initiator at 160 degrees C in N-2 atmosphere by varying the catalyst concentration and temperature. The catalytic activity of the metal-MA hybrid towards the ROP of CL was evidenced by the FTIR-RI method. The % yield, degradation temperature (T-d), melting temperature (T-m) and molecular weight (M-w) of poly(epsilon-caprolactone) (PCL) were also investigated. The structure of PCL was comprehended by analysing its NMR spectrum. The activation energy (E-a) for the ROP of CL was determined as 10,363 kcal/mol. A linear increase in M-w of PCL with the increasing [M-0/I-0] ratio was also noticed. [GRAPHICS] .

Automated summary

The Mn2+ and Mo6+ based metal-mercaptoacetate hybrids were successfully synthesized using a simple acid-base titration method, and characterized by various analytical techniques. The hybrids were found to exhibit catalytic activity towards the ring-opening polymerization of epsilon-caprolactone, leading to an increase in the molecular weight of the product.