Effect of Mesoporous Silica Nanoparticles in the biodegradation of Polyoxymethylene polymer

The engineering thermoplastic polyoxymethylene (POM) is a polymer of formaldehyde. Even though it is believed to replace the usage of metals, it also degrades easily under many circumstances like heat, acids, alkalis, oxygen, abrasion, enzymes, radiations etc. This work aims to study the degradation of POM Nano composite with Mesoporous Silica Nanoparticle (MSN) and pure POM at periodical intervals. Degradation in two different atmospheres viz., natural withering and soil buried condition were studied. The POM materials were characterized with Tensile strength, Diffused Reflectance Spectroscopy (DRS) and Fourier Transform Infra Red Spectroscopy (FTIR), before and after degradation. These characterizations revealed that tensile strength of the pure POM material was lost significantly after six months of natural withering whereas POM nanocomposite with MSN showed no significant loss, indicating stability of the material due to MSN. Both DRS and FTIR supported this result. By DRS, it was identified that the optical property of the materials increased due to degradation. FTIR shows differences in the peak intensity for the aldehyde group after degradation. In all the cases soil buried samples showed quick degradation. Hence, microbial analysis was done with soil buried POM samples. Physical, biochemical and molecular characterization confirmed that the isolated organism was Methylobacterium sp.