Fabrication of effective polyamide-amine acrylonitrile-butadiene-styrene composites using recycled ABS waste plastic for removal of malachite green from aqueous solutions

In this study, polyamide-amine acrylonitrile–butadiene–styrene (PAABS) composites were fabricated using pyromellitic anhydride (PMDA) as a chelating agent and tetraethylenepentamine (TEPA) as a cross-linking agent via two-step chemical process. Dicarboxylic diketo-functionalized ABS (DDABS) was synthesized using RABS and PMDA with AlCl₃ as a catalyst via Friedel–Craft acylation and N-methyl-2-pyrrolidone (NMP) as a solvent. Functionalized ABS was treated TEPA and N, N’-diisopropylcarbodiimide (DIC) via amidation reactions to form PAABS with amide–amine repeating units. Functionalized PAABS was used as an effective adsorbent for the removal of malachite green (MG) dye from aqueous medium. The crystallinity, functional groups, and surface morphology of PAABS were studied using XRD, FTIR and SEM analysis respectively. Adsorption parameters were optimized, and kinetics, isotherms and thermodynamic parameters were evaluated using adsorption experimental date. The result suggests that derived q_e (416 mg/g) value of second-order kinetics is well matched with experimental q_e values (408 mg/g) and the maximum monolayer adsorption capacity was found to be 383 mg/g. Finally, the adsorbed–adsorbent was blended with PLA (MG-PAABS/PLA) to convert into thin film and filaments to avoid solid pollution. Mechanical properties (569 kgf/cm²) and stability of thin film and filaments were performed to enhance the properties of waste by-products.

Graphical abstract