Collaborative Research: Variothermal Roll-to-Roll Embossing Process for Rapid and Precision Production of Large-Area Microstructures

这个合作研究项目的目的是确定是否可以实现可接受的复制保真度的连续压花工艺制造的大面积聚合物薄膜上的微结构。 该方法是用具有改变辊表面温度的能力的压花辊对聚合物膜进行压花。这种温度在轧辊圆周上的空间变化将使用一种创新的高频加热方法来实现，利用这种方法可以实现每秒超过100 ℃的温度变化率。 实验将观察快速加热对聚合物薄膜的可行性及其对聚合物变形行为的影响。 在此基础上，建立了该聚合物微加工工艺的预测数学模型。如果成功，这项研究将导致一种新的制造工艺，用于在聚合物薄膜上制造微结构。基本的贡献，预计有关的建模和材料行为的聚合物变形的压花为基础的过程。具体而言，该研究将推进理解的变形的无定形聚合物与尖锐的温度梯度和这种介观状态的行为的发展的流动模式在压花过程中的影响。此外，这种新的制造方法预计将在具有精确尺寸、高纵横比、尖锐半径和脆边的微结构的质量和成本效益方面发挥至关重要的作用。该方法将进一步有利于传统的薄膜纹理化工业在开发新的应用与地形相关的表面功能，以前不能实现。 此外，该项目的跨学科性质将扩大研究生和本科生的教育和培训。预计该项目的成果将丰富更广泛的课程开发工作，特别是在聚合物加工，计量学和微/纳米技术领域。

The objective of this collaborative research project is to determine if a continuous embossing process for fabrication of microstructures on large-area polymer films can be achieved with acceptable replication fidelity. The approach is to emboss the polymer film with an embossing roll that has an ability of varying the roll surface temperature. This spatial variation of temperature over the roll circumference will be accomplished using an innovative high-frequency heating method, with which a rate of temperature change exceeding 100C per second can be achieved. Experiments will be conducted to observe the feasibility of the rapid heating on polymer films and its effect on the deformation behavior of polymers. Further, a predictive mathematical model for this innovative polymer microfabrication process will be established based on the experimental verifications. If successful, this research will lead to a new manufacturing process for fabricating microstructures on polymeric films. Fundamental contributions are anticipated regarding the modeling and material behavior of polymer deformation in embossing based processes. Specifically, the research will advance understanding of deformation of amorphous polymers with sharp temperature gradient and the influence of such meso-state behavior on the development of the flow pattern during the embossing processes. Moreover, this new manufacturing method is expected to play a vital role in terms of quality and cost-effective fabrication of microstructures with accurate dimensions, high aspect ratios, sharp radii, and crispy edges. The process would further benefit the traditional film texturing industry in the development of novel applications with topography-related surface functionalities that cannot be realized before. In addition, the interdisciplinary nature of the project will broaden the education and training of graduate and undergraduate students. It is expected that the results of the project will enrich broader curriculum development efforts, particularly in the areas of polymer processing, metrology, and micro/nano technology.