Zuccarello Bernardo, Bartoli Mattia, Bongiorno Francesco, Militello Carmelo, Tagliaferro Alberto, Pantano Antonio
Dipartimento di Ingegneria, Università degli Studi di Palermo, 90128 Palermo, Italy.
Department of Applied Science and Technology (DISAT), Politecnico di Torino, 10129 Torino, Italy.
Polymers (Basel). 2021 Jan 8;13(2):198. doi: 10.3390/polym13020198.
Biocomposites are increasingly used in the industry for the replacement of synthetic materials, thanks to their good mechanical properties, being lightweight, and having low cost. Unfortunately, in several potential fields of structural application their static strength and fatigue life are not high enough. For this reason, several chemical treatments on the fibers have been proposed in literature, although still without fully satisfactory results. To overcome this drawback, in this study we present a procedure based on the addition of a carbonaceous filler to a green epoxy matrix reinforced by Agave sisalana fibers. Among all carbon-based materials, biochar was selected for its environmental friendliness, along with its ability to improve the mechanical properties of polymers. Different percentages of biochar, 1, 2, and 4 wt %, were finely dispersed into the resin using a mixer and a sonicator, then a compression molding process coupled with an optimized thermomechanical cure process was used to produce a short fiber biocomposite with Vf = 35%. Systematic experimental tests have shown that the presence of biochar, in the amount 2 wt %, has significant effects on the matrix and fiber interphase, and leads to an increase of up to three orders of magnitude in the fatigue life, together with an appreciable improvement in static tensile strength.
由于具有良好的机械性能、重量轻且成本低，生物复合材料在工业中越来越多地被用于替代合成材料。不幸的是，在几个潜在的结构应用领域中，它们的静态强度和疲劳寿命还不够高。因此，文献中提出了几种对纤维进行化学处理的方法，尽管仍未取得完全令人满意的结果。为了克服这一缺点，在本研究中，我们提出了一种方法，即在由龙舌兰纤维增强的绿色环氧基体中添加碳质填料。在所有碳基材料中，选择生物炭是因为其环境友好性以及改善聚合物机械性能的能力。使用混合器和超声仪将1%、2%和4%（重量）的不同百分比的生物炭精细地分散到树脂中，然后采用压缩成型工艺并结合优化的热机械固化工艺来制备体积分数Vf = 35%的短纤维生物复合材料。系统的实验测试表明，2%（重量）的生物炭的存在对基体和纤维界面有显著影响，使疲劳寿命提高了多达三个数量级，同时静态拉伸强度也有明显提高。
