Enhancing marine biodegradability of poly(butylene succinate) by blending with 16-hydroxyhexadecanoic acid and poly(ε-caprolactone)

Abstract

One potential solution for reducing marine pollution from plastic waste is to replace conventional plastics with biodegradable alternatives. However, most chemosynthetically biodegradable aliphatic polyesters, such as poly(butylene succinate) (PBS), exhibit extremely slow biodegradation rates in marine environments. To address this problem, we present a novel method to enhance the marine biodegradability of PBS by blending it with 10 wt.% of 16-hydroxyhexadecanoic acid (16HHD) and poly(ε-caprolactone) (PCL). The weight loss rates of the PBS samples with 16HHD and PCL were 18.4- and 7.8-times faster than that of pristine PBS. Scanning electron micrographs of PBS blended with 16HHD and PCL after oceanic incubation for four months showed a rough surface, suggesting that enzymatic degradation occurred. Additionally, unlike pristine PBS, samples with 16HHD and PCL demonstrated biochemical oxygen demand (BOD) biodegradabilities of 90.4% and 83.2%, respectively, under marine conditions. Analysis of the microbial community of BOD testing using 16S ribosomal RNA gene sequencing indicated that the addition of 16HHD and PCL changed the microbial community compared to pristine PBS. These findings demonstrate how blending PBS with 16HHD and PCL enhances its marine biodegradability, thereby offering a promising avenue for addressing plastic pollution in marine ecosystems.