碳纳米管（CNT）对聚合物基体的力学增强一直未取得突破性进展，归因于CNT难于分散及其随机取向性。本工作结合定向CNT阵列制备技术的最新进展，将其与传统碳纤维进行优化复合，制备一种新型的碳纳米管阵列/碳纤维叠层复合材料；与传统碳纤维复合材料相比，其不仅具有更低的纤维含量和密度，而且还具有更高的弯曲模量和更优异的阻尼性能（表现为更长的周期负荷使用寿命），其归因于连续碳纤维和定向CNTs的力学增强协同效应。通过这种将传统纤维与纳米纤维进行优化设计和组装，可获得性能更为优异的新型复合材料；为设计多功能复合材料和CNT的大规模工业化应用提供了新的途径和设计思路，可在国防工业、航空航天、建筑结构、交通运输等领域得以广泛应用。

　　该工作“Design and Reinforcement: Vertically Aligned Carbon Nanotube-Based Sandwich Composites”于2010年发表于美国化学学会（ACS）主办的著名期刊 ACS Nano（影响因子9.855），审稿人给予该论文高度的评价：“I was impressed by this paper. The authors seem to put a lot of effort looking for the right combination of Carbon Fibers (CF) and the vertically aligned carbon nanotube (VACNT) composite structures and extensive testing of prepared CF-VACNT-CF composites.---- ， The manuscript makes the impression of a well done and well documented work and can certainly be published.”（这篇论文给我留下了深刻的印象，作者通过大量细致的工作寻找碳纤维和定向碳纳米管的最佳组合---，这篇论文是一篇出色的、结构完整的工作，确实值得发表）；“It could be an interesting paper and worthy to be published inACS Nano---”（这是一篇有趣的论文、值得在ACS Nano 上发表---）。

　　Figure 1. Structures and fabrication of the VACNT sandwich. (a) SEM image of the VACNT sandwich at a low magnification (scale bar, 1 mm). (b) The freestanding VACNTs and their substrate are about 50 mm long and 20 mm wide. (c) The VACNT sandwich was fabricated by using a VARTM technique, which consists of stacking a CF/VACNT/CF sandwich structure, evacuating air, infiltrating resin, and curing procedures. (d) The VACNT sandwich shows a good infiltration of VACNTs with epoxy (scale bar, 5 μm). (e) The VACNT sandwich retains a good alignment of CNTs along the through-thickness direction (scale bar, 1 μm). (f) Rough fracture surfaces in CNT-rich regions imply a tough fracture of the composites compared with smooth fracture surfaces of neat epoxy (scale bar, 50 μm). (g) The VACNT sandwich exhibits a good infiltration of VACNTs with epoxy and a good alignment of the CNTs (scale bar, 5 μm).

　　Figure 2. Dynamic mechanical analyses of the CF/Ep laminate and the VACNT sandwich in a three-point bending mode, reflecting responses of molecular motions to cyclic loads at different temperatures. (a) The VACNT sandwich (blue triangle) exhibits higher storage modulus than the CF/Ep laminate (red circle) due to the vertical alignment of CNTs and the resulting remarkable reinforcement of shear modulus. (b) The deformation of specimens in the three-point bending mode involves a bending deformation and a shearing deformation. (c) The higher loss modulus of the VACNT sandwich than that of the CF/Ep laminate implies high dissipation of energy during cyclic deformations. (d) The VACNT sandwich shows higher damping (a higher value of tan [1]) than the CF/Ep laminate. (e) The VACNT sandwich exhibits a lower mass fraction of fillers, lower density, and higher specific stiffness than the CF/Ep laminate.

　　发表论文刊物：Y. Zeng*, L. Ci, B. Carey, R. Vajtai, P. M. Ajayan*. Design and Reinforcement: Vertically Aligned Carbon Nanotube-based Sandwich Composites, ACS Nano, 2010, 4(10): 6798-6804.