Thang Q. Tran, Sayyam Deshpande, Smita Shivraj Dasari, Kailash Arole, Denis Johnson, Yufan Zhang, Ethan M. Harkin, Abdoulaye Djire, Hang Li Seet, Sharon Mui Ling Nai, and Micah J. Green ACS Applied Materials Interfaces 2024 16 (50), 69929-69939
Abstract:
Here we demonstrate direct ink write (DIW) additive manufacturing of carbon nanotube (CNT)/phenolic composites with heat dissipation and excellent electromagnetic interference (EMI) shielding capabilities without curing-induced deformation. Such polymer composites are valuable for protecting electronic devices from overheating and electromagnetic interference. CNTs were used as a multifunctional nanofiller to improve electrical and thermal conductivity, printability, stability during curing, and EMI shielding performance of CNT/phenolic composites. Different CNT loadings, curing conditions, substrate types, and sample sizes were explored to minimize the negative effects of the byproducts released from the cross-linking reactions of phenolic on the printed shape integrity. At a CNT loading of 10 wt %, a slow curing cycle enables us to cure printed thin-walled CNT/phenolic composites with highly dense structures; such structures are impossible without a filler. Moreover, the electrical conductivity of the printed 10 wt % CNT/phenolic composites increased by orders of magnitude due to CNT percolation, while an improvement of 92% in thermal conductivity was achieved over the neat phenolic. EMI shielding effectiveness of the printed CNT/phenolic composites reaches 41.6 dB at the same CNT loading, offering a shielding efficiency of 99.99%. The results indicate that high CNT loading, a slow curing cycle, flexible substrates, and one thin sample dimension are the key factors to produce high-performance 3D-printed CNT/phenolic composites to address the overheating and EMI issues of modern electronic devices.
License type:
Attribution 4.0 International (CC BY 4.0)
Funding Info:
This research / project is supported by the A*STAR Graduate Academy - A*STAR International Fellowship program
Grant Reference no. : NA