Abstract
The massive accumulation of plastic packaging wastes in the natural environment is surging at a breakneck pace, highlighting the significance of sustainable alternatives. We have previously reported that Kraft paper (KP) coated by crosslinked poly(vinyl alcohol) (PVA) (henceforth referred to as KP-PVA) features remarkable oxygen and water vapor barrier along with mechanical properties comparable to most commodity plastics. Here, we demonstrate that this same KP-PVA can be significantly biodegraded in the marine environment. The biodegradation test was conducted by employing respirometry per ASTM D6691-17. The KP-PVAs were mineralized (59.2–81.6%) into CO2 in 111 days. Depolymerization of polymer chains and surface degradation of KP-PVAs were evidenced using Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The intensive disintegration of KP-PVA was synergistically driven by both biotic and abiotic factors (mechanical stress). Moreover, the in vitro biocompatibility test for MEF (mouse embryonic fibroblasts) and HEK293 (human embryonic kidney cells), and in vivo biocompatibility test with mice proved that the KP-PVA is safe and does not endanger marine life. These results suggest that the KP-PVA could be a sustainable alternative to non-degradable plastic packages polluting the marine environment.
