Studying the effect of biosilver nanoparticles on polyethylene degradation

The current study is focussed on the silver nanoparticle (AgNP)-based degradation of polyethylene. Two kinds of polyethylenes were usedlinear high-density polyethylene and branched low-density polyethylene. Owing to the demerits of chemically synthesized nanoparticles, the biological synthesis of AgNPs from Aspergillus oryzae was carried out. The AgNPs produced were used along with the culture broth for the degradation studies. This nanoparticle-based method for bioremediating the polyethylene proved to be successful since it could degrade 64.5% of low-density polyethylene (LDPE) and 44.4% of high-density polyethylene (HDPE) in 5weeks. The action of nanoparticles on polyethylene wax emulsion caused the thinning of the fluid. The HDPE samples when subjected to FTIR exhibited bending and stretching of the C-H bonds which form the backbone of the linear polymer. The degraded LDPE showed formation of phenols, alcohols, ketones and other smaller compounds, indicating the breakdown of the branched plastic. The GC-MS studies of the nanoparticle-treated polyethylene revealed the liberation of esters, alcohols and alkenes in HDPE, and aldehydes, alkenes, cyano compounds, esters and alkanes in LDPE. The 100% concentration of the AgNPs-treated degradation products of polyethylene was found to be 34.36% toxic in Allium cepa when compared with 97.35% phytotoxicity of the polyethylene wax emulsion.