School of Materials Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive, Atlanta, Georgia 30332, USA.
ACS Appl Mater Interfaces. 2010 Sep;2(9):2637-45. doi: 10.1021/am100456m.
We show the fast preparation of printable highly conductive polymer nanocomposites for future low-cost electronics. Highly conductive polymer nanocomposites, consisting of an epoxy resin, silver flakes, and incorporated silver nanoparticles, have been prepared by fast sintering between silver flakes and the incorporated silver nanoparticles. The fast sintering is attributed to: 1) the thermal decomposition of silver carboxylate-which is present on the surface of the incorporated silver flakes-to form in situ highly reactive silver nanoparticles; 2) the surface activation of the incorporated silver nanoparticles by the removal of surface residues. As a result, polymer nanocomposites prepared at 230 °C for 5 min, at 260 °C for 10 min, and using a typical lead-free solder reflow process show electrical resistivities of 8.1×10(-5), 6.0×10(-6), and 6.3×10(-5) Ω cm, respectively. The correlation between the rheological properties of the adhesive paste and the noncontact printing process has been discussed. With the optimal rheological properties, the formulated highly viscous pastes (221 mPa s at 2500 s(-1)) can be non-contact-printed into dot arrays with a radius of 130 μm. The noncontact printable polymer nanocomposites with superior electrical conductivity and fast processing are promising for the future of printed electronics.
我们展示了一种用于未来低成本电子设备的可打印高导电性聚合物纳米复合材料的快速制备方法。通过快速烧结银薄片和掺入的银纳米粒子之间的银薄片和掺入的银纳米粒子，制备了由环氧树脂、银薄片和掺入的银纳米粒子组成的高导电性聚合物纳米复合材料。快速烧结归因于：1）银羧酸盐的热分解 - 存在于掺入的银薄片的表面上 - 形成原位高反应性银纳米粒子; 2）通过去除表面残留物对掺入的银纳米粒子的表面活化。结果，在 230°C 下制备 5 分钟，在 260°C 下制备 10 分钟，并且使用典型的无铅焊料回流工艺，聚合物纳米复合材料的电阻率分别为 8.1×10（-5），6.0×10（-6）和 6.3×10（-5）Ω cm。讨论了胶黏剂糊料的流变性能与非接触印刷工艺之间的相关性。具有最佳流变性能的配方高粘性糊料（在 2500 s（-1）时为 221 mPa s）可以非接触印刷成 130 μm 半径的点阵列。具有优异导电性和快速加工性能的非接触式可打印聚合物纳米复合材料有望成为印刷电子技术的未来。
