纤维膜在机械压力下由不透明到透明的转变
王超 , 赵景 , 刘柳 , 张鹏 , 王先锋 , 俞建勇 , 丁彬
工程(英文) ›› 2022, Vol. 19 ›› Issue (12) : 84 -92.
纤维膜在机械压力下由不透明到透明的转变
Transformation of Fibrous Membranes from Opaque to Transparent Under Mechanical Pressing
智能可穿戴设备、电子皮肤、空气过滤和组织工程等领域,对透明薄膜材料或基材的需求很大。传统透明材料,如玻璃、塑料等,由于缺乏相互连通的孔道、不理想的孔隙率和柔性,不能满足这些新兴领域的要求。静电纺丝纤维膜因其具有小孔径、高孔隙率和良好的柔性等优点可以弥补传统材料的不足,因此,开发透明的静电纺丝纤维膜具有重大的价值。本文报道了一种简单有效的方法,在不使用任何其他添加剂的情况下,通过机械压力,直接将静电纺丝纤维膜制备成柔性的、有孔的透明纤维膜材料。同时,首次总结了压制后聚合物的透明度性能与分子结构之间的关系。经过机械压力处理后,纤维膜仍可以保持纤维形态、微米级孔道和一定的孔隙率。以聚苯乙烯静电纺丝纤维膜为例,所制备的透明聚苯乙烯纤维膜具有优异的光学性能和机械性能。透明纤维膜可实现高透光率(≈89%,可见光波长在550 nm处)、大孔隙率(10%~30%)和强的机械拉伸强度(≈148 MPa),该拉伸强度约为初始静电纺丝纤维膜的78倍。此外,本文基于透明纤维膜,利用真空辅助抽滤银纳米线和机械压力作用,制备出透明的导电纤维膜材料。与氧化铟锡导电薄膜相比,我们所制备的透明导电纤维膜展示出良好的导电性(9 Ω·sq-1,78%的透光率)和优异的机械性能(可承受大量的弯曲应力)。
There is a great demand for transparent films, membranes, or substrates in the fields of intelligent wearables, electronic skins, air filtration, and tissue engineering. Traditional materials such as glass and plastics cannot satisfy these requirements because of the lack of interconnected pores, undesirable porosity, and flexibility. Electrospun fibrous membranes offset these shortcomings because they contain small pores and have high porosity as well as outstanding flexibility. Thus, the development of transparent electrospun fibrous membranes is of great value. This work reports a simple and effective way to develop flexible and porous transparent fibrous membranes (TFMs) directly from electrospun fibrous membranes via mechanical pressing, without employing any other additives. In addition, the relationship between the transparency performance and the molecular structure of the polymers after pressing was summarized for the first time. After mechanical pressing, the membranes maintained fibrous morphology, micron-sized pores, and desired porosity. Polystyrene fibrous membranes, which exhibited excellent optical and mechanical properties, were used as a reference. The TFMs possessed high transparency (∼89% visible light transmittance at 550 nm), high porosity (10%–30%), and strong mechanical tensile strength (∼148 MPa), nearly 78 times that of the pristine electrospun fibrous membranes. Moreover, this study demonstrated that transparent and conductive membranes can be fabricated based on TFMs using vacuum-assisted filtration of silver nanowires followed by mechanical pressing. Compared with indium tin oxide films, conductive TFMs exhibited good electrical conductivities (9 Ω per square (Ω·sq−1), 78% transmittance at 550 nm) and notable mechanical performance (to bear abundant bending stresses).
透明 / 静电纺丝纤维膜 / 孔道结构 / 机械压力 / 导电
Transparent / Electrospun fibrous membranes / Porous structure / Mechanical pressing / Conductivity
/
| 〈 |
|
〉 |