Poly(butylene adipate-co-terephthalate) (PBAT) is a biodegradable polymer derived from fossil-based raw materials. Combined with poly(lactic acid) (PLA), a major material used in 3D printing, PBAT provides mechanical properties that are particularly attractive for applications requiring flexible 3D-printed objects. However, blends with high PBAT content in fused filament fabrication (FFF) are currently not well-documented, and optimal printing parameters remain unclear for advancing this field. This study aims to address this gap by first exploring the extrusion of filaments at different temperatures, followed by analyzing the printing conditions for PBAT/PLA blends to enhance their spectrum of applications. Using a commercial blend, Ecovio (R) (86 mol% PBAT), this paper demonstrates the feasibility of employing high PBAT content in the additive manufacturing process. Printing parameters such as nozzle temperature and speed were assessed based on the visual quality and mechanical properties of the specimens. The results indicate that extruding at 120 degrees C yields smoother filaments with adequate diameter for FFF applications. Regarding 3D-printing analysis, variations in parameters did not significantly impact elongation at break. However, increasing the nozzle temperature from 180 to 210 degrees C and the printing speed from 50 to 80 mm/s resulted in a 29% increase in tensile strength and a 77% increase in the modulus of elasticity of the 3D-printed specimens which is attributed to better interlayer adhesion. Therefore, high PBAT content blends can improve the performance of 3D-printed materials, and parameters must be optimized to exploit their effectiveness fully across various industrial uses.Highlights Extrusion temperature variations minimally affect PLA/PBAT thermal properties. Higher nozzle temperature and speed significantly improve mechanical properties. Optimal printing conditions for high PBAT blends enable flexible materials. PBAT blends show potential for enhanced 3D printing performance in all sectors.
The preservation of the ancient seawall site is a focal point and challenge in the protection of historical relics along Hangzhou's Grand Canal in China. This endeavor holds significant historical and contemporary value in uncovering and perpetuating Hangzhou's cultural heritage. Researchers investigating the Linping of the seawall site aimed to address soil site deterioration by selecting environmentally friendly alkali-activated slag cementitious materials and applying the response surface method (RSM) to conduct solidification experiments on the seawall soil. Researchers used the results of unconfined compressive strength tests and microscopic electron microscopy analysis, considering the comprehensive performance of soil solidification mechanisms and mechanical properties, to establish a least-squares regression fitting model to optimize the solidification material process parameters. The experimental results indicate that the optimal mass ratio of lime, gypsum, and slag for achieving the best solidification process parameters for the seawall soil, with a 28-day curing period, is 1:1.9:6.2. This ratio was subsequently applied to the restoration and reconstruction of the seawall site, with parts of the restored seawall exhibited in a museum to promote the sustainable conservation of urban cultural heritage. This study provides theoretical support and practical guidance for the protection and restoration of soil sites.