Bar Avia J, Mead Joey, Dodiuk Hanna, Kenig Samuel
Department of Plastics Engineering, University of Massachusetts Lowell, Lowell, Massachusetts01854, United States.
Department of Polymers and Plastics Engineering, Shenkar College of Engineering and Design, Ramat-Gen52526, Israel.
ACS Omega. 2022 Nov 7;7(45):40766-40774. doi: 10.1021/acsomega.2c01991. eCollection 2022 Nov 15.
We report an innovative approach to creating stretchable conductive materials composed of a tubular shell made from braided carbon nanotube yarns (CNTYs) embedded in an elastomeric matrix. For stretchable electronics, both mechanical properties and electrical conductivities are of interest. Consequently, both the mechanical behavior and electrical conductivities under large deformations were investigated. A new hyperelastic composite model was developed to predict the large deformation response to applied stress for a braid in a tubular elastomer composite. The composite demonstrated a hyperelastic response due to the architecture of the braid, and the behavior was affected by the braiding angle, braid modulus, and volume fraction of fibers. The elastomer matrix was considered a neo-Hookean material and represented by the Yeoh model. An interaction parameter was proposed to account for the effect of the elastomer/braid cooperative restriction as observed in experimental and calculated results. This novel approach enabled the determination of the constitutive behavior of the composite in large deformations (>150%), taking into account the elastomer and yarn properties and braid configurations. The model exhibited good agreement with the experimental results. As the CNTYs are conductive, a stretchable conductive composite was obtained having a resistivity of 5.01 × 10 and 5.67 × 10 Ω·cm for the 1-ply and 4-ply composites, respectively. The resistivity remained constant through cyclic loading under large deformations in tension until mechanical failure. The material has potential for use in stretchable electronics applications.
我们报道了一种创新方法，用于制备由嵌入弹性体基质中的编织碳纳米管纱线（CNTYs）制成的管状外壳组成的可拉伸导电材料。对于可拉伸电子产品而言，机械性能和电导率都备受关注。因此，我们研究了在大变形情况下的机械行为和电导率。开发了一种新的超弹性复合模型，以预测管状弹性体复合材料中编织物在施加应力下的大变形响应。由于编织结构，该复合材料表现出超弹性响应，并且其行为受编织角度、编织模量和纤维体积分数的影响。弹性体基质被视为新胡克材料，并由Yeoh模型表示。提出了一个相互作用参数，以解释在实验和计算结果中观察到的弹性体/编织物协同限制的影响。这种新颖的方法能够确定复合材料在大变形（>150%）情况下的本构行为，同时考虑到弹性体和纱线的性能以及编织结构。该模型与实验结果表现出良好的一致性。由于CNTYs具有导电性，分别获得了1层和4层复合材料，其电阻率分别为5.01×10和5.67×10Ω·cm的可拉伸导电复合材料。在大变形拉伸循环加载直至机械失效的过程中，电阻率保持恒定。该材料具有用于可拉伸电子应用的潜力。
