Insights into the biodegradation of PHA / wood composites: Micro- and macroscopic changes

Abstract

et al., Insights into the biodegradation of PHA / wood composites: Micro-and macroscopic changes, Sustainable Materials and Technologies,

Review of recent advances in the biodegradability of polyhydroxyalkanoate (PHA) bioplastics and their composites

“…215 Other natural soil biodegradation studies include soil sourced from South African agricultural fields, black soil and leaf mould, oil palm cultivation soil, soil from Russia and Vietnam, and soil from California landfills. Field soil and landfill soil appear to have the highest rate of PHA biodegradation activity, being the only samples approaching 100% PHA degradation 142,144,151,175,181,205,223,224 (Table 1, entries 1 and 4-7). This may be due to the microbial diversity found in moist soil with consistent environments that maximize microbial population growth and diversity.…”

“…PHA/ wood flour 50/50 composites under natural and laboratory conditions are reported to show wood flour degradation improvements although the two studies vary from 12.5% in 365 days to 50% in 84 days respectively, which can be attributed to the higher surface area and moisture in laboratory studies. 165,224 Furthermore, depending on the type of wood flour the lignin content can vary from 21-34%. 303 The presence of lignin is still not enough to determine if the biodegradation rate will be impacted and to what extent.…”

Scanning Electron Microscopy and Atomic Force Microscopy: Topographic and Dynamical Surface Studies of Blends, Composites, and Hybrid Functional Materials for Sustainable Future

“…A network of fungal hyphae filaments has been embedded in the matrix with the presence of spores. e decreases in molar mass of PHA throughout 12 months of soil burial became more severe as the wood content increased [23]. e degradation of PLA and its composites with starch in compost and soil also indicates the process catalysed by enzymes in the case of composites.…”

Exploring the role of biodegradable plastics

“…In regards to the influence of the material characteristics, surface phenomena, particularly roughness, can influence bacterial attachment and enzymatic action (Woolnough et al, 2013), as can porosity (Chan et al, 2019;Tsuji and Suzuyoshi, 2003) and crystallinity (Spyros et al, 1997). The type of polymer processing (solvent cast, melt pressed, extruded), post processing treatment, and surface chemistries (e.g.…”

“…A deeper understanding of these factors influencing biodegradation rates will require studies to investigate targeted comparisons between samples as opposed to just considering biodegradation in general. In particular, studies are required that look at the influence of shape, surface morphology, porosity, additives and processing techniques as they have the potential to be used as controlling factors (Chan et al, 2019;Sridewi et al, 2006;Tsuji and Suzuyoshi, 2003). There has also been no targeted consideration of the method of production of the PHA objects tested, the processing additives, or the post-processing methodology, although this influences the material properties and potentially the biodegradation rate (Cherpinski et al, 2017;Follain et al, 2014;Laycock et al, 2017).…”