Bio-Compatible Ca-BDC/Polymer Monolithic Composites Templated from Bio-Active Ca-BDC Co-Stabilized CO2-in-Water High Internal Phase Emulsions

Evaluation of stress-controlled high-cycle fatigue characteristics in PLA-wood fused deposition modeling 3D-printed parts under bending loads

PLA (Poly-lactic acid)-wood provides more biodegradability through natural fibers, a significant advantage of pure PLA. Nevertheless, these bio-composites may have inferior mechanical properties compared to non-degradable polymer composites, considering the lower strength of natural particles compared to synthetic fibers. This research examines the fatigue behavior of additive-manufactured biopolymer PLA-wood and assesses its comparability with pure PLA. Therefore, solid fatigue test samples were printed using the FDM (fused deposition modeling) method. Afterward, fully reversed rotary bending fatigue experiments were performed at 4 different stress levels (7.5 to 15 MPa) to extract the S-N curve of PLA-wood. Moreover, the fatigue fracture surfaces of the PLA-wood were investigated and compared at the highest and lowest stress levels using an FE-SEM (Field Emission Scanning Electron Microscopy), indicating more ductile fracture marks at higher stress levels. The fatigue lifetime of the PLA-wood decreased by 87.48% at the highest stress level (15 MPa), rather than the result at the lowest stress level (7.5 MPa). Additionally, the results demonstrated that the fatigue characteristics of the printed pure PLA and PLA-wood were comparable, suggesting that the 3D-printed PLA-wood with the used printing parameters can be an alternative choice.

Enzymatic Upcycling of PET Waste to Calcium Terephthalate for Battery Anodes

Biotechnological recycling offers a promising solution to address the environmental concerns associated with waste plastics, particularly polyethylene terephthalate (PET), widely utilized in packaging materials and textiles. To advance the development of a bio-based circular plastic economy, innovative upcycling strategies capable of generating higher-value products are needed. In this study, we enhanced the enzymatic depolymerization of waste PET by incorporating highly concentrated calcium ions (up to 1 m) to the hydrolytic reaction catalyzed by the best currently known enzyme LCCICCG . The presence of calcium ions not only improved the thermal stability and activity of the biocatalyst but also significantly reduced the consumption of base required to maintain optimal pH levels. Employing optimized conditions at 80 °C for 12 h, we successfully converted ≈84 % of the waste PET (200 g L-1 ) into solid hydrated calcium terephthalate (CaTP ⋅ 3H2 O) as the primary product instead of soluble terephthalate salt. CaTP ⋅ 3H2 O was easily purified and employed as a raw material for battery electrode production, exhibiting an initial reversible specific capacity of 164.2 mAh g-1 . Through techno-economic analysis, we conclusively demonstrated that the one-pot biocatalysis-based synthesis of CaTP is a superior PET upcycling strategy than the secondary synthesis method employing recycled terephthalic acid.

Interconnectivity and morphology control of poly-high internal phase emulsions under photo-polymerization

We here demonstrate that the interconnectivity and morphology of photo-polymerized HIPEs can be controlled by changing the type of initiators and stabilizers, and the intensity of light.