Li Baozhang, Xu Chengyi, Zheng Jianming, Xu Chunye
CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China.
Sensors (Basel). 2014 Jun 4;14(6):9889-99. doi: 10.3390/s140609889.
We have developed a highly sensitive flexible pressure sensor based on a piezopolymer and silver nanowires (AgNWs) composite. The composite nanofiber webs are made by electrospinning mixed solutions of poly(inylidene fluoride) (PVDF) and Ag NWs in a cosolvent mixture of dimethyl formamide and acetone. The diameter of the fibers ranges from 200 nm to 500 nm, as demonstrated by SEM images. FTIR and XRD results reveal that doping Ag NWs into PVDF greatly enhances the content of β phase in PVDF. This β phase increase can be attributed to interactions between the Ag NWs and the PVDF matrix, which forces the polymer chains to be embedded into the β phase crystalline. The sensitivity of the pressure sensors agrees well with the FTIR and XRD characteristics. In our experiments, the measured sensitivity reached up to 30 pC/N for the nanofiber webs containing 1.5 wt% Ag NWs, which is close to that of poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE), (77/23)]. This study may provide a new method of fabricating high performance flexible sensors at relatively low cost compared with sensors based on [P(VDF-TrFE), (77/23)].
我们基于压电聚合物和银纳米线（AgNWs）复合材料开发了一种高灵敏度柔性压力传感器。复合纳米纤维网是通过在二甲基甲酰胺和丙酮的共溶剂混合物中静电纺丝聚偏氟乙烯（PVDF）和AgNWs的混合溶液制成的。如扫描电子显微镜图像所示，纤维直径范围为200纳米至500纳米。傅里叶变换红外光谱（FTIR）和X射线衍射（XRD）结果表明，将AgNWs掺杂到PVDF中可大大提高PVDF中β相的含量。这种β相含量的增加可归因于AgNWs与PVDF基体之间的相互作用，这种相互作用迫使聚合物链嵌入β相晶体中。压力传感器的灵敏度与FTIR和XRD特性吻合良好。在我们的实验中，对于含有1.5 wt% AgNWs的纳米纤维网，测得的灵敏度高达30 pC/N，这与聚（偏氟乙烯-三氟乙烯）[P（VDF-TrFE），（77/23）]的灵敏度相近。与基于[P（VDF-TrFE），（77/23）]的传感器相比，本研究可能提供一种以相对低成本制造高性能柔性传感器的新方法。
