SBIR Phase I: Die Optimization Software for Coextruded Multilayer Plastic Products

这个小企业创新研究（SBIR）第一阶段项目的更广泛的影响/商业潜力是减少多层塑料产品共挤出模具的开发时间和成本。本项目开发的模头优化软件将使共挤模头设计的交付时间缩短至少50%，从而为每个模头设计节省15，500 - 22，500美元。该项目的模具优化软件也将提高共挤出产品的质量。共挤塑料产品的应用范围从汽车零件、住房和建筑，到医疗手术期间使用的管材。优化的共挤模头将提高所有这些应用的产品质量。模具优化软件也将被许多大学用于学术研究，以及在塑料工程课程中教授挤出模具设计。该优化软件还将提高对聚合物共挤出中遇到的各种复杂性背后的根本原因的科学理解。该项目的智力价值是开发一种数学算法，该算法将能够优化不同类型的共挤出模具的几何形状，包括用于挤出片材，管材和复杂型材的模具。 共挤出模头设计的主要挑战是开发一种模头几何形状，该模头几何形状将在模头出口处提供均匀的速度分布，并且还将在共挤出产品中提供所需的层结构。如果聚合物离开模具时不同部分的出口速度不同，则材料在出来后会重新分布-这可能会扭曲挤出产品的形状。共挤模头仍然主要使用“试错法”设计。对于复杂的共挤模头，这种通过试错法进行的微调不仅需要2到3个月的时间才能达到最终的模头设计，而且还需要经验丰富的工程师，很少能提供最佳的模头设计。本项目开发的模具优化软件将消除这种试错法，代之以基于科学的数学算法。为了评估每个模具设计，该优化软件将使用最近开发的流动模拟软件，该软件可以准确预测共挤出模具中的层结构的发展沿着多层共挤出产品的模后变形。

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase I project is the reduction in the development time and cost of the dies employed for coextrusion of multilayer plastic products. The die optimization software which will be developed in this project will reduce the lead time for coextrusion die design by at least 50%, resulting in a saving of $15,500-22,500 for each die design. The die optimization software from this project will also improve the quality of the coextruded products. Coextruded plastic products are used in application ranging from automotive parts, housing and construction, to tubing used during medical operations. Optimized coextrusion dies will improve the quality of products for all these applications. The die optimization software will also be used by many universities for academic research as well as to teach extrusion die design in their plastics engineering curriculum. This optimization software will also enhance the scientific understanding of the root cause behind various complexities encountered in polymer coextrusion.The intellectual merit of this project is development of a mathematical algorithm which will be able to optimize the geometry of different types of coextrusion dies including those used for extrusion of sheets, pipes, and complex profiles. The main challenge in design of a coextrusion die is to develop a die geometry which will give a uniform velocity distribution at the die exit and will also provide the required layer structure in the coextruded product. If exit velocity is different in different portions as polymer exits the die, the material is redistributed after it comes out - which can distort the shape of the extruded product. Coextrusion dies are still mostly designed using a "trial-and-error" approach. For complex coextrusion dies, this fine-tuning by trial-and-error not only takes 2 to 3 months to reach the final die design, but also requires highly experienced engineers and rarely provides an optimum die design. The die optimization software which will be developed in this project will eliminate this trial-and-error approach, replacing it with a science-based mathematical algorithm. To evaluate each die design, this optimization software will use a recently developed flow simulation software that can accurately predict the development of layer structure in coextrusion dies along with the post-die distortion of multilayer coextruded products.