In this study, polydiacetylene (PDA) is embedded in electrospun polyvinylidene fluoride (PVDF) nanofibers for the preparation of mats with dual colorimetric and piezoelectric responses. The diacetylene monomers are self-assembled during the electrospinning process. The PDA-embedded PVDF nanofibers in the blue phase are obtained via photo-polymerization upon UV-light irradiation. The colorimetric transition of the nanofibers is studied as a function of temperature using a spectrophotometer. The morphology and crystal polymorphism of the nanofibers are investigated. The results show that the addition of PDA increases the diameter of the nanofibers due to the increase in the electrospinning solution viscosity. The results of Fourier transform infrared and wide angle X-ray diffraction demonstrate that PDA has the effect of inhibiting the growth of non-polar α-phase crystals, while promoting the growth of the polar β-phase. However, the red phase of PDA-embedded PVDF exhibits a lower intensity of the β-phase in comparison to that of the blue phase. In fact, the blue-to-red color transition of the PDA-embedded electrospun PVDF nanofibers is accompanied by the variation of piezoelectric signaling caused by variations in the β-phase. This phenomenon creates great potential in commercial detection sensors in addition to their colorimetric detection properties.

中文翻译：

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聚二乙炔包埋的电纺聚偏二氟乙烯纳米纤维的晶体多态性

在这项研究中，聚二乙炔（PDA）嵌入电纺聚偏二氟乙烯（PVDF）纳米纤维中，用于制备具有比色和压电响应的垫子。在电纺丝过程中，二乙炔单体是自组装的。蓝相中嵌入PDA的PVDF纳米纤维是通过以下方法获得的在紫外光照射下进行光聚合。使用分光光度计研究了纳米纤维的比色转变与温度的关系。研究了纳米纤维的形貌和晶体多态性。结果表明，由于电纺丝溶液粘度的增加，PDA的添加增加了纳米纤维的直径。傅里叶变换红外和广角X射线衍射的结果表明，PDA具有抑制非极性α相晶体生长，同时促进极性β相生长的作用。然而，与蓝色相相比，嵌入PDA的PVDF的红色相显示出较低的β相强度。实际上，嵌入PDA的电纺PVDF纳米纤维的蓝色到红色过渡伴随有β相变化引起的压电信号变化。除了比色检测特性外，这种现象还在商用检测传感器中创造了巨大的潜力。