Apigenin/furfurylamine-based bio-polyamide/cyclophosphazene composite: Preparation and dual applications in dye adsorption and Pb (II) electrochemical probing

Abstract

The construction of polymer/phosphazene organic-inorganic hybrids using biomass can improve the sustainability of their preparation. In addition, introducing diverse functional units to these hybrids is a potential way to broaden their downstream applications. Herein, a benzoxazine derivative (AP-f), prepared from biomasses (apigenin and furfurylamine), is used as starting materials to construct a polymer/phosphazene hybrid. Through efficient benzoxazine-isocyanide-mechanochemistry (BIC-MC), a bio-polyamide derivative (PA-af) containing diverse molecular fragments (amide, phenolic hydroxyl, and tertiary amine) is prepared by solid-state ball-milling. Using PA-af as a phenolic source, a novel polyamide (PA)/phosphazene organic-inorganic hybrid (PACP-af) is successfully constructed by condensation with hexachlorocyclotriphosphazene (HCCP). PACP-af shows selective adsorption for cationic dye methylene blue (MB). Experimental results show that the maximum adsorption capacity of MB by PACP-af reaches 598.4 mg/g, and the adsorption process followed the pseudo-second-order kinetic and Langmuir adsorption model. PACP-af is also used as an enrichment-type Pb (II) electrochemical probe with an acceptable detection range (1–100 μM) and detection limit (0.085 μM).