Viscoelastic Characterization of Poly(3-hexylthiophene): Determination of Young’s Modulus
Viscoelastic Characterization of Poly(3-hexylthiophene): Determination of Young’s Modulus
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DOI：
10.1021/acsapm.3c00939
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发表时间：
2023-07
影响因子：
5
通讯作者：
Branston E. Mefferd;V. V. Nambiar-V.;Hongbing Lu;M. Stefan
中科院分区：
文献类型：
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作者：
Branston E. Mefferd;V. V. Nambiar-V.;Hongbing Lu;M. Stefan
纳米压痕是测量薄膜力学性能的最佳技术。聚合物呈现出一个独特的问题，即它们对负载的响应是时间相关的。因此，许多最常见的纳米压痕方法不适合探测聚合物的纳米级性质。尽管这个问题已经众所周知了几十年，聚（3-己基噻吩）一直是通过与时间无关的机械性能测试方法来分析的。在此，我们提出了一种纳米压痕技术，分析了材料在恒速率加载和阶跃加载下的时间依赖性响应。通过确定粘弹性函数，我们能够提取聚（3-己基噻吩）的杨氏弛豫模量。粘弹性纳米压痕的平均杨氏模量为260±27 MPa。这些结果与薄膜的专门机械测试非常一致，并显示出对其他有机半导体材料分析的希望。
Nanoindentation is an optimal technique for the measurement of thin film mechanical properties. Polymers present a unique problem in that their response to loading is time-dependent. Due to this, many of the most common nanoindentation methods are not suitable for probing polymer nanoscale properties. Despite this issue being well-known for decades, poly(3-hexylthiophene) has been exclusively analyzed by time-independent mechanical properties testing methods. Herein, we present a nanoindentation technique that analyzes the materials’ time-dependent response under both constant rate loading and step loading. By determining viscoelastic functions, we are able to extract the Young’s relaxation modulus of poly(3-hexylthiophene). The average Young’s modulus acquired from viscoelastic nanoindentation is determined to be 260 ± 27 MPa. These results are in excellent agreement with specialized mechanical tests for thin films and show promise for the analysis of other organic semiconducting materials.