Sousa Dora, Baleia Catarina, Amaral Pedro
Instituto de Engenharia Mecânica (IDMEC), Instituto Superior Técnico, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal.
Polymers (Basel). 2025 Feb 28;17(5):662. doi: 10.3390/polym17050662.
Waste stone sludge generated by the extractive industry has traditionally posed significant disposal challenges. This study redefines stone sludge as a valuable raw material by incorporating it into polylactic acid (PLA) to create sustainable composite materials. Pellets and filaments composed of up to 50% by weight of limestone powder and PLA were successfully produced using melt blending in a twin-screw extruder. Scanning electron microscopy (SEM), X-ray fluorescence (XRF), and X-ray diffraction (XRD) analyses revealed a uniform distribution of stone particles within the PLA matrix and confirmed the chemical and structural compatibility of the components. Thermogravimetric analysis (TGA) showed that the composites retained thermal stability, while mechanical testing demonstrated significant enhancements in stiffness, with an increase in elastic modulus for composites containing 50% limestone powder. The melt flow rate (MFR) decreases with increasing filler content. The brittleness also increased, reducing impact resistance. Mechanical tests were performed on injected and 3D-printed specimens. The filament produced was successfully used in 3D printing, with a small XYZ calibration cube.
采掘业产生的废石污泥传统上带来了重大的处置挑战。本研究通过将其融入聚乳酸（PLA）以制造可持续复合材料，将石污泥重新定义为一种有价值的原材料。使用双螺杆挤出机通过熔融共混成功生产出了由高达50%（重量）的石灰石粉末和PLA组成的颗粒和长丝。扫描电子显微镜（SEM）、X射线荧光光谱（XRF）和X射线衍射（XRD）分析表明，石颗粒在PLA基体中分布均匀，并证实了各组分的化学和结构相容性。热重分析（TGA）表明复合材料保留了热稳定性，而力学测试表明刚度有显著提高，含50%石灰石粉末的复合材料的弹性模量有所增加。熔体流动速率（MFR）随填料含量的增加而降低。脆性也增加了，降低了抗冲击性。对注塑和3D打印试样进行了力学测试。所生产的长丝成功用于3D打印，制作了一个小型XYZ校准立方体。
