Collaborative Research: Elastic and Viscoelastic Characterization and Modeling of Polymer Based Structures for Biological Applications

该奖项的研究目标是促进对软聚合物材料机械响应机制的科学理解，以便设计和构建有效的微/纳米结构和生物医学应用设备。 弹性和粘弹性表征和建模的软聚合物材料，即聚二甲基硅氧烷（PDMS），将进行。 这样的聚合物材料将在不同的尺度下进行探测，从散装到微米/纳米水平使用冲压试验，和纳米压痕技术。 结果将实施到一个粘弹性有限元分析模型开发串联。 经验证的模型最终将用于根据测量的PDMS柱阵列偏转来确定活细胞的机械力。 为此，所提出的研究将需要粘弹性材料的表征和细胞力测量应用的理论或数值粘弹性建模的发展之间的平衡。 从PDMS的粘弹性的深入研究的科学见解将有助于在生物医学行业中常用的微/纳米尺度的许多其他软聚合物材料的分析。 其愿景是通过开发新的理论模型和实验方法，扩大科学和工程界在小规模探测软聚合物材料的能力。 这些表征技术和平台将使科学家能够提出与生物医学研究相关的深刻而棘手的问题，并获得定量的经验答案，其分辨率足以在小尺度上表征软材料。 该奖项将实施和传播一项教育和培训计划，通过软聚合物材料微/纳米表征的综合研究机会，在生物和纳米力学的边界上开发跨学科的思维模式。 该项目将包括本科生和研究生研究，这两个机构的研究生教育，并推广到高中学生。

The research objective of this award is to contribute to the scientific understanding of the mechanisms of the mechanical response of soft polymer materials so as to permit the design and construction of effective micro/nano structures and devices for biomedical applications. Elastic and viscoelastic characterization and modeling of a soft polymer material, namely polydimethylsiloxane (PDMS), will be performed. Such a polymer material will be probed at different scales from bulk down to the micro/nano levels using punch tests, and nanoindentation techniques. The results will be implemented into a viscoelastic finite element analysis model developed in tandem. The validated model will ultimately be utilized to determine the mechanical forces of living cells from the measured deflection of PDMS pillar arrays. To this end, the proposed research would entail a balance between characterization of the viscoelastic material and the development of a theoretical or numerical viscoelastic modeling for cellular force measurement applications. The scientific insights from the in-depth study of the viscoelasticity of PDMS will contribute to the analysis of many other soft polymer materials at micro/nano scales commonly used in biomedical industries. The vision is to expand the science and engineering community's capacity to probe soft polymer materials at small scales by developing both new theoretical models and experimental methodologies. These characterization techniques and platforms will allow scientists to ask profound and previously intractable questions related to biomedical research, and to obtain quantitative empirical answers with resolution sufficient to characterize the soft materials in small scales. This award will implement and disseminate an educational and training program that develops interdisciplinary modes of thought at the boundary of bio- and nano-mechanics through integrated research opportunities in micro/nano characterization of soft polymer materials. The project will incorporate undergraduate and graduate research, graduate education at both institutions and also outreach to high-school students.