Effect of inoculation on storage and loss moduli of high density polyethylene/cellulose blend

Plastic materials, particularly Polyethylene (PE) are the potential source of environmental pollution. In the present study, a fungal strain was isolated from the dumpsite capable of adhering to High density polyethylene (HDPE) and its cellulose (CELL) blends surface. The fungal strain was identified as Aspergillus niger. Dynamic mechanical analysis (DMA) was used to monitor the effect of Aspergillus niger on the HDPE/CELL blends. The viscoelastic behavior of HDPE/CELL blends was studied to give an insight on the dynamic mechanical properties such as storage modulus, loss modulus. The relaxation processes were greatly affected by inoculation. The intensity of both α and β peaks significantly reduced on inoculation due to the degradation of the blends by A.niger. The β-relaxation was heavily affected by inoculation suggesting that microbial attack started in the crystalline-amorphous interface. However, the crystalline part was also affected by the degradation process. Vogel-Fulcher-Tamman(VFT) model offered a better understanding of the time-temperature dependence of the mean relaxation frequency (τ)for the blends.