Centre for Composite Materials, Department of Mechanical Engineering, Kalasalingam Academy of Research and Education, Krishnankoil 626 126, Tamilnadu, India; Department of Mechanical and Process Engineering, The Sirindhorn International Thai-German Graduate School of Engineering (TGGS), King Mongkut's University of Technology North Bangkok, Bangkok 10800, Thailand.
Department of Aerospace Engineering, Faculty of Engineering, Universiti Putra Malaysia, Serdang 43400, Malaysia.
Int J Biol Macromol. 2019 Dec 1;141:1-13. doi: 10.1016/j.ijbiomac.2019.08.231. Epub 2019 Aug 28.
Bio-composites are easy to manufacture and environmentally friendly, could reduce the overall cost and provide lightweight due to the low density of the natural fibers. In a bid to compete with the synthetic fiber reinforced composites, a single natural fiber composite may not be a good choice to obtain optimal properties. Hence, hybrid composites are produced by adding two or more natural fibers together to obtain improved properties, such as mechanical, physical, thermal, water absorption, acoustic and dynamic, among others. Regarding thermal stability, the composites showed a significant change by varying the individual fiber compositions, fiber surface treatments, addition of fillers and coupling agents. The glass transition temperature and melting point obtained from the thermomechanical analysis and differential scanning calorimetry are not the same values for several hybrid composites, since the volume variation was not always parallel with the enthalpy change. However, the difference between the temperature calculated from the thermomechanical analysis and differential scanning calorimetry was lower. Significantly, this critical reviewed study has a potential of guiding all composite designers, manufacturers and users on right selection of composite materials for thermal applications, such as engine components (covers), heat shields and brake ducts, among others.
生物复合材料易于制造且环保，由于天然纤维的低密度，可降低整体成本并提供轻质效果。为了与合成纤维增强复合材料竞争，单一的天然纤维复合材料可能不是获得最佳性能的理想选择。因此，通过添加两种或更多种天然纤维来生产混合复合材料，以获得改善的性能，例如机械性能、物理性能、热性能、吸水性、声学性能和动态性能等。关于热稳定性，通过改变单个纤维成分、纤维表面处理、添加填料和偶联剂，复合材料的热稳定性发生了显著变化。从热机械分析和差示扫描量热法获得的玻璃化转变温度和熔点并非所有混合复合材料的相同值，因为体积变化并不总是与焓变平行。然而，从热机械分析和差示扫描量热法计算出的温度之间的差异较小。值得注意的是，这项重要的综述研究有可能为所有复合材料设计师、制造商和用户提供指导，帮助他们正确选择用于发动机部件（罩盖）、隔热罩和制动导管等热应用的复合材料。
