[SCIENCE CHINA Materials] Controlled length and number of thermally conductive pathways for copper wire/poly(lactic acid) composites via 3D printing
作者:Tengbo Ma, Kunpeng Ruan, Yongqiang Guo*, Yixin Han and Junwei Gu
关键字:thermally conductive pathways
论文来源:期刊
具体来源:SCIENCE CHINA Materials
发表时间:2024年
Tengbo Ma, Kunpeng Ruan, Yongqiang Guo*, Yixin Han and Junwei Gu*. Controlled length and number of thermally conductive pathways for copper wire/poly(lactic acid) composites via 3D printing. SCIENCE CHINA Materials, 2023, 66(10): 4012 - 4021. 2022IF=8.1.
https://www.sciengine.com/SCMs/doi/10.1007/s40843-023-2540-9
Abstract
Thermal conduction pathways play a crucial role in understanding the thermal behavior of thermally conductive polymer composites, yet there is a lack of in-depth research on the mechanism of how the properties of thermal conduction pathways (length, number) affect the thermal conductivity of polymer composites. In this study, one-dimensional copper wire/poly(lactic acid) (1D Cw/PLA) thermally conductive composites with controllable length and quantity of copper wire (Cw) thermal conduction pathways were fabricated using 3D printing technology. A thermal conduction model for polymer composites with one-dimensional thermal conduction pathways was established, elucidating the quantitative relationship between the properties of thermal conduction pathways and their thermal performance. With the same Cw content, the in-plane thermal conductivity (λ//) of 1D Cw/PLA thermally conductive composites is positively correlated with the number and length of thermal conduction pathways. When the Cw volume fraction is 25.1 vol%, the λ// of the 1D Cw/PLA thermally conductive composites containing 20 Cw intact thermal conduction pathways can reach up to 4.23 W/(m·K), which is 87.2% higher than the λ// of the 1D Cw/PLA thermally conductive composites without Cw intact thermal conduction pathways (2.26 W/(m·K)), 72.0% higher than the λ// of the 1D Cw/PLA thermally conductive composites containing short Cw (2 intact Cw, 18 broken at 1/2 point Cw) (2.46 W/(m·K)), and 1527% higher than the λ// of the pure PLA matrix (0.26 W/(m·K)). Using the thermal conduction model and empirical equations constructed in this study, the thermal conductivity of 1D Cw/PLA composites was predicted, and it was found that there was no significant difference between the predicted values and the measured values at a 95% confidence level.
导热通路对理解导热高分子复合材料的导热行为至关重要,但目前有关导热通路属性(长度、数量)对高分子复合材料导热系数的影响机制缺乏深入的研究。本文采用3D打印技术制备了铜线(Cw)导热通路长度和数量可控的一维铜线/聚乳酸(1D Cw/PLA)导热复合材料,建立了针对一维导热通路的高分子复合材料的导热模型,明晰了其导热通路属性与其导热性能的定量关系。相同Cw用量下,1D Cw/PLA导热复合材料的面内导热系数(λ//)与导热通路的数量和长度成正相关。当Cw体积分数为25.1 vol%时,含20根Cw贯穿导热通路的1D Cw/PLA导热复合材料的λ//最高可达4.23 W/(m·K),比相同Cw用量下不含Cw贯穿导热通路的1D Cw/PLA导热复合材料λ//(2.26 W/(m·K))高87.2%,比相同Cw用量下含短Cw(2根贯穿的Cw,18根在1/2处被打断的Cw)的1D Cw/PLA导热复合材料的λ//(2.46 W/(m·K))高72.0%,较纯PLA基体的λ//(0.26 W/(m·K))提高了1527%。采用本文构建的导热模型和经验方程对1D Cw/PLA复合材料的导热系数进行预测,95%的置信度认为预测值与实测值无显著差异。