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Biodegradable polymeric materials derived from renewable resources have attracted tremendous attention in different application. Polylactic acid (PLA) is one of the most useful biodegradable polymers. It is difficult to synthesize high molecular weight polylactic acid by direct polycondensation. The present work describes the synthesis of high molecular weight PLA by varying the duration of reaction and changing the sequence of catalyst addition. Binary catalyst used was SnCl2.2H2O/maleic anhydride and p-toluene sulfonic acid. PLA with molecular weight (6.503X105) was obtained in 50 hours. FTIR, H1 and 13C NMR ascertained the structure of synthesized PLA whereas GPC was used for determining molecular weight.

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In the present study, unsaturated polyester resins based on castor oil was synthesized. Structure elucidation of the synthesized unsaturated polyester resin was done by FTIR and 1H NMR spectroscopy. Thermogravimetric analysis was used to evaluate the thermal stability of cured unsaturated polyester resin. Thermogram plot was further utilized to calculate various other parameters such as statistic heat-resistant index (Ts) and the integral procedural decomposition temperature (IPDT). Comparable properties with respect to commercial resins were reported for the synthesized polymers

Raw banana fiber (RBF), acid treated banana fiber (ATBF) from banana stem was evaluated as adsorbent for the elimination Cd 2+ from solution. The Cd 2+ solution of 1000 mg/L concentration was prepared from Cd(NO3)2 and different concentrations were prepared by dilution of stock solution. Effects of adsorbent dose, contact time, temperature, initial metal concentration and pH study were evaluated. Langmuir and Freundlich isotherms were employed to describe adsorption capacity The maximum amounts of cadmium(II) adsorbed (qm), which was evaluated by Langmuir isotherm, were 0.469 mg/g and 5.230 mg/g, and highest R 2 (0.9968, 0.9815,) for raw banana fiber and acid treated banana fiber, respectively. Pseudo-second order kinetics best fitted with R 2 = (0.9457), (0.9571) for raw banana fiber and acid treated banana fiber, respectively. Thermodynamic parameters obtained were ∆G° (-8.268) kJ mol -1 K -1 , ∆H° (-9.874), kJ mol -1 K -1 and ∆S° (-5.152) kJ mol -1 for acid treated banana fiber and spontaneity decreases with increase in temperature in case of raw banana fiber and acid treated banana fiber. This indicates that the system is exothermic. Banana stems possess feasible characteristics for making an adsorbent and acid treated banana fiber is more efficient for removal of Cd 2+ ion from its aqueous solution.