Pop Mihai Alin, Cosnita Mihaela, Croitoru Cătălin, Zaharia Sebastian Marian, Matei Simona, Spîrchez Cosmin
Materials Science Department, Transilvania University of Brasov, 29 Eroilor Ave., 500484 Brasov, Romania.
Department of Product Design, Mechatronics and Environment, Transilvania University of Brasov, 29 Eroilor Ave., 500484 Brasov, Romania.
Polymers (Basel). 2023 May 28;15(11):2487. doi: 10.3390/polym15112487.
The first part of this paper is dedicated to obtaining 3D-printed molds using poly lactic acid (PLA) incorporating specific patterns, which have the potential to serve as the foundation for sound-absorbing panels for various industries and aviation. The molding production process was utilized to create all-natural environmentally friendly composites. These composites mainly comprise paper, beeswax, and fir resin, including automotive function as the matrices and binders. In addition, fillers, such as fir needles, rice flour, and (horsetail) powder, were added in varying amounts to achieve the desired properties. The mechanical properties of the resulting green composites, including impact and compressive strength, as well as maximum bending force value, were evaluated. The morphology and internal structure of the fractured samples were analyzed using scanning electron microscopy (SEM) and an optical microscopy. The highest impact strength was measured for the composites with beeswax, fir needles, recyclable paper, and beeswax fir resin and recyclable paper, 19.42 and 19.32 kJ/m, respectively, while the highest compressive strength was 4 MPa for the beeswax and horsetail-based green composite. Natural-material-based composites exhibited 60% higher mechanical performance compared to similar commercial products used in the automotive industry.
本文的第一部分致力于使用聚乳酸（PLA）制作带有特定图案的3D打印模具，这些模具有可能成为各行业及航空领域吸音板的基础。成型生产工艺被用于制造全天然环保复合材料。这些复合材料主要由纸、蜂蜡和枞树脂组成，其中汽车用材料作为基体和粘合剂。此外，还添加了不同数量的填料，如枞针、米粉和（木贼）粉末，以达到所需性能。对所得绿色复合材料的力学性能进行了评估，包括冲击强度、抗压强度以及最大弯曲力值。使用扫描电子显微镜（SEM）和光学显微镜对断裂样品的形态和内部结构进行了分析。含蜂蜡、枞针、可回收纸以及蜂蜡枞树脂和可回收纸的复合材料的冲击强度最高，分别为19.42和19.32 kJ/m，而以蜂蜡和木贼为基础的绿色复合材料的最高抗压强度为4 MPa。与汽车行业使用的类似商业产品相比，基于天然材料的复合材料的机械性能高出60%。
