Large-scale Additive Manufacturing of Highly Exothermic Reactive Polymer Systems
Large-scale Additive Manufacturing of Highly Exothermic Reactive Polymer Systems
复制标题
高放热反应性聚合物体系的大规模增材制造
DOI：
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发表时间：
2019
期刊：
影响因子：
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通讯作者：
V. Kunc
中科院分区：
文献类型：
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作者：
S. Romberg;C. Hershey;J. Lindahl;W. Carter;B. Compton;V. Kunc
反应性聚合物体系的添加剂制造(AM)涉及在室温下沉积材料，这些材料要么在打印过程中通过化学引发的反应固化，要么在打印后需要热引发。本文重点介绍了化学引发热固性树脂的大规模AM，以表征热产生、依赖于温度的粘弹性和交联性对印刷过程的影响。使用红外(IR)和光学视觉系统，结合选定的材料染料，研究了在构建过程中对温度和固化前沿的实时跟踪。观察到先前沉积层内的热产生导致新沉积层的存储模数(G‘)和粘度显著降低，从而导致珠子不稳定和打印失败。对薄壁结构的定量实验观察提出了通过选择印刷参数和调整原料树脂的粘弹性性质来缓解这种失效模式的策略。
Additive manufacturing (AM) of reactive polymer systems involves the deposition of materials at room temperature that either cure during printing through a chemically initiated reaction or require thermal initiation after printing. This presentation focuses on large-scale AM of chemically initiated thermosetting resins to characterize the effects of heat generation, temperature-dependent viscoelasticity, and crosslinking on the printing process. Real-time tracking of both temperature and cure fronts during the build process were investigated using infrared (IR) and optical vision systems in combination with selected material dyes. Heat generation within the previouslydeposited layers was observed to cause significant reduction in the storage modulus (G’) and viscosity of newly-deposited layers, resulting in bead instabilities and failure of the print. Quantitative experimental observations on thin-wall structures suggest strategies for mitigating this failure mode through selection of print parameters and tailoring of viscoelastic properties of the feedstock resin.