SBIR Phase I: High-resolution High-speed Dynamic Nanoindenter to Measure Viscoelastic Properties of Soft Materials

这个小型企业创新研究第一阶段项目旨在测试一种新技术的可行性，以研究生物材料、细胞、组织、聚合物和纳米复合材料等软材料的机械性能。与现有技术相比，提出的方法将提供更高的空间分辨率，并将软材料的粘弹性属性映射速度提高100倍以上。此外，建议的技术将使用户能够在进行测量的同时测试纳米级应变-应力关系的线性(这种线性信息对于正确计算刚性系数至关重要)。我们将通过原子力显微镜(AFM)，通过同时测量多个频率(而不是像目前在现有的纳米压头上所做的那样，顺序地)，用纳米级探针分析材料的粘弹性(频率相关)特性。这将加快任何材料的测量速度，但也将代表着材料研究的真正突破。除了提高测量速度外，还将有更高的空间分辨率，因为不需要等待软材料的缓慢松弛(一种称为“蠕变”的现象)。该项目的更广泛的影响/商业潜力将是能够绘制软材料的机械粘弹性特性图，与现有的纳米压痕相比，空间分辨率和速度显著提高(超过100倍)。这将为在纳米尺度上研究聚合物、纳米复合材料、生物材料和组织的纳米力学增加一个新的维度。这一解决方案将对纳米压头(2010年市场规模为5000万美元)和原子力显微镜(市场规模超过5亿美元)的用户具有商业价值。更广泛地说，这一工具对于从事生物纳米技术(约1000-1500亿美元)、生物材料(250亿美元)和聚合物(2000多亿美元)领域的研究人员来说将是无价的。这项工作将导致为现有的原子力显微镜开发一种附件(硬件和软件)，并最终作为一个独立的系统来测量软材料的独特粘弹性特性光谱。

This Small Business Innovation Research Phase I project is aimed at testing the feasibility of a new technology for studying the mechanical properties of soft materials, such as biomaterials, cells, tissues, polymers, and nanocomposites. The proposed method will provide substantially higher spatial resolution and increase the speed of mapping viscolelastic properties of soft materials, by a factor of more than 100 versus existing technology. In addition, the proposed technique will give users the ability to test the linearity of strain-stress relation at the nanoscale while performing the measurements (such linearity information is paramount for proper calculation of the rigidity modulus). We will analyze viscoelastic (frequency-dependent) properties of materials with a nanoscale probe through atomic force microscopy (AFM), by measuring multiple frequencies at the same time (rather than sequentially, as is currently done in existing nanoindenters). This will accelerate the measurements for any material, but will also represent a true breakthrough for materials research. Besides increased measurement speed, a substantially higher spatial resolution will be attached because there will be no need to wait for the slow relaxation of soft materials (a phenomenon called "creep").The broader impact/commercial potential of this project will be to enable mapping of mechanical viscoelastic properties of soft materials with dramatically improved spatial resolution and speed (by more than a factor of 100) as compared to existing nanoindenters. This will add a new dimension to the study of the nanomechanics of polymers, nanocomposites, biomaterials, and tissues at the nanoscale. This solution will be commercially valuable for the users of nanoindenters (representing a $50 million market in 2010) and AFMs (representing a market of more than half a billion dollars). More broadly, this tool will be invaluable for researchers working in the areas of bio-nanotechnology (~$100-150 billion), biomaterials ($25 billion), and polymers ($200+ billion). The work done in this effort will result in the development of an attachment (both hardware and software) for existing AFMs, and eventually, as a stand-alone system to measure the unique spectra of viscoelastic properties of soft materials.