Kumar Vineet, Alam Md Najib, Manikkavel Amutheesan, Song Minseok, Lee Dong-Joo, Park Sang-Shin
School of Mechanical Engineering, Yeungnam University, 280, Daehak-ro, Gyeongsan 38541, Korea.
Graduate School of Mechanical Engineering, Yeungnam University, 280, Daehak-ro, Gyeongsan 38541, Korea.
Polymers (Basel). 2021 Jul 15;13(14):2322. doi: 10.3390/polym13142322.
Without fillers, rubber types such as silicone rubber exhibit poor mechanical, thermal, and electrical properties. Carbon black (CB) is traditionally used as a filler in the rubber matrix to improve its properties, but a high content (nearly 60 per hundred parts of rubber (phr)) is required. However, this high content of CB often alters the viscoelastic properties of the rubber composite. Thus, nowadays, nanofillers such as graphene (GE) and carbon nanotubes (CNTs) are used, which provide significant improvements to the properties of composites at as low as 2-3 phr. Nanofillers are classified as those fillers consisting of at least one dimension below 100 nanometers (nm). In the present review paper, nanofillers based on carbon nanomaterials such as GE, CNT, and CB are explored in terms of how they improve the properties of rubber composites. These nanofillers can significantly improve the properties of silicone rubber (SR) nanocomposites and have been useful for a wide range of applications, such as strain sensing. Therefore, carbon-nanofiller-reinforced SRs are reviewed here, along with advancements in this research area. The microstructures, defect densities, and crystal structures of different carbon nanofillers for SR nanocomposites are characterized, and their processing and dispersion are described. The dispersion of the rubber composites was reported through atomic force microscopy (AFM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The effect of these nanofillers on the mechanical (compressive modulus, tensile strength, fracture strain, Young's modulus, glass transition), thermal (thermal conductivity), and electrical properties (electrical conductivity) of SR nanocomposites is also discussed. Finally, the application of the improved SR nanocomposites as strain sensors according to their filler structure and concentration is discussed. This detailed review clearly shows the dependency of SR nanocomposite properties on the characteristics of the carbon nanofillers.
没有填料时，诸如硅橡胶之类的橡胶类型表现出较差的机械、热和电性能。传统上，炭黑（CB）用作橡胶基体中的填料以改善其性能，但需要高含量（接近每百份橡胶60份（phr））。然而，这种高含量的CB常常会改变橡胶复合材料的粘弹性。因此，如今使用诸如石墨烯（GE）和碳纳米管（CNT）之类的纳米填料，它们在低至2 - 3 phr时就能显著改善复合材料的性能。纳米填料被归类为那些至少有一维尺寸低于100纳米（nm）的填料。在本综述论文中, 基于碳纳米材料的纳米填料如GE、CNT和CB，从它们如何改善橡胶复合材料性能的角度进行了探讨。这些纳米填料能显著改善硅橡胶（SR）纳米复合材料的性能，并已用于广泛的应用，如应变传感。因此，这里对碳纳米填料增强的SR进行了综述，以及该研究领域的进展。对用于SR纳米复合材料的不同碳纳米填料的微观结构、缺陷密度和晶体结构进行了表征，并描述了它们的加工和分散情况。通过原子力显微镜（AFM）、透射电子显微镜（TEM）和扫描电子显微镜（SEM）报道了橡胶复合材料的分散情况。还讨论了这些纳米填料对SR纳米复合材料的机械性能（压缩模量、拉伸强度、断裂应变、杨氏模量、玻璃化转变）、热性能（热导率）和电性能（电导率）的影响。最后，根据其填料结构和浓度，讨论了改进后的SR纳米复合材料作为应变传感器的应用。这篇详细的综述清楚地表明了SR纳米复合材料性能对碳纳米填料特性的依赖性。
