Gautam Das

Bio-based Sulfonated Epoxy/Hyperbranched Polyurea-modified MMT Nanocomposites

Hyperbranched polyurea modified nanoclay was used for the preparation of vegetable oil modified sulfone epoxy nanocomposites at different loadings (1–5 wt%) for the first time. The bio-based nanocomposites were characterized by XRD, SEM, TEM, and FTIR techniques. These nanocomposites showed an enhancement of thermal stability up to 48°C as revealed by thermo-gravimetric analysis. The nanocomposites with 5 wt% of nanoclay exhibited more than 300 percent improvement in tensile strength, though the elongation at break decreases with the increase of nanoclay loading. Thus the studied nanocomposites possess better performance over the pristine system.

Biodegradable and biocompatible epoxidized vegetable oil modified thermostable poly(vinyl chloride): thermal and performance characteristics post biodegradation with Pseudomonas aeruginosa and Achromobacter sp.

The increased production of municipal solid waste by the disposal of plastic materials heightens the urgency to develop biodegradable materials for daily use. In vitro-biodegradation study on poly(vinyl chloride) (PVC) plasticized by epoxidized Mesua ferrea L. seed oil at three different weight percentages (PVC/ENO ratio of 75/25, 50/50 and 25/75) was conducted by using Pseudomonas aeruginosa and Achromobacter sp. bacteria. The test bacterial species were able to grow on the polymer matrix by using it as a source of energy; however the pristine PVC did not support the microbial growth. The PVC/ENO material of 25/75 ratio showed the highest percent (%) of biodegradation compared to other tested systems. The bacterial count and the dry biomass post 180 days of inoculation in 25/75 plasticized PVC suggested bacterial growth at the expense of degradation of the system. The tensile strength of 25/75 PVC/ENO system, post 180 days of inoculation by Pseudomonas aeruginosa and Achromobacter sp. decreased by about 53% and 43% respectively. Further, surface erosion phenomenon and structural change of the matrix after bacterial growth, as studied by FTIR and SEM analysis of PVC/ENO of 25/75 ratio exhibited noticeable deterioration post 180 days of inoculation.