阿基米德螺旋型二维纳米复合纤维的制备及性能研究

The introduction of nanomaterials in the processing of polymer fibers can produce nanocomposite fibers with unique properties (or performance enhancement) and specific functions. However, conventional nanofillers have relatively simple functions, and it is difficult for them to achieve a uniform, continuous, and high-efficiency reinforcement of the fiber, while traditional composite-processing methods are difficult to realize a controllable dispersion of nanofillers. These problems significantly limit the realization of the high function and device application of polymer nanocomposite fibers. To this end, in this project, working from the perspective of designing nanofillers and regulating their dispersion structures, we propose the concepts of using two-dimensional (2D) continuous nanofillers to achieve the maximum enhancement of the structural performance and functional properties of composite materials and applying the increment-dimensional processing method starting from 2D films to 3D fibers to precise control the dispersion of nanofillers. An automatic transverse shearing technology will be used to carry out the composite-processing of 2D semiconductors such as MoS2 and the thermoplastic polymer matrix like polyethylene terephthalate to realize a continuous fabrication of nanocomposite fibers containing continuous 2D filler components that follow an Archimedean spiral (or vortex) dispersion. Meanwhile, the mechanical properties of the fibers and their performance as fiber-device components in photoelectric converting and sensing will be studied systematically. The research of this project has important scientific significance and application value for the development of sophisticated functional fiber devices.

在聚合物纤维的加工过程中引入纳米材料，可制得具有特殊性能（或性能提升）和特定功能的纳米复合纤维。但是，传统纳米填料功能性相对单一且难以实现纤维均匀、连续且高效的增强，传统复合加工方法则难以实现纳米材料的可控分散，这极大地限制了聚合物纳米复合纤维的高功能化及器件应用。为此，本项目从纳米填料设计及分散结构调控的角度出发，通过利用二维连续纳米填料实现复合材料结构性能和功能性的最大增强、二维薄膜到三维纤维的增维加工方法实现填料可控分散的设计思路，采用自动化的横向剪切滚动技术，进行二维半导体如二硫化钼与热塑性聚合物如聚对苯二甲酸乙二酯的复合加工，实现二维填料组分连续且呈阿基米德螺旋型（涡卷型）分散的纳米复合纤维的连续定制。同时系统研究纤维的力学性能及其在光电转化和传感等方向的器件应用。本项目的研究对复杂功能纳米复合纤维器件的开发有着重要科学意义和重大应用价值。

在聚合物中可控地引入纳米材料，制备出高性能的聚合物纳米复合纤维，是赋予惰性的聚合物材料各种功能性、实现纤维材料功能器件化的重要途径。其关键在于纳米填料的可控制备与可控分散。而目前受纳米填料自身的尺寸限制以及直接共混的复合方式难以实现纳米材料在纤维中均匀、有序且连续的分布，极大地限制了高性能纳米复合纤维的开发。由此，本项目从功能性纳米材料的可控制备、聚合物基体的结构定制、功能纳米复合材料的可控加工三个方面展开研究。首先实现了大面积单层石墨烯的化学气相沉积生长、二维共价有机框架（COF）材料的结构定制、还原氧化石墨烯（rGO）纳米片的可控制备与修饰以及1T相单层二硫化钼（MoS2）纳米片的大量制备，这些结构可控、功能丰富的纳米材料可以为复合材料带来电学、光学、抗老化等丰富的功能特性，是制备多功能纳米复合材料的制备奠定了基础；进一步通过单体序贯加料策略，结合硫醇-烯点击化学反应制备了动态交联聚烯烃弹性体，其作为高性能聚合物基体为复合材料的设计和应用提供了更加广泛的可能性；最后利用双向拉伸、横向剪切滚动等加工方法，实现了上述二维材料在不同聚合物基体如热塑性树脂聚碳酸酯（PC）、聚苯乙烯（PS），聚烯烃弹性体（POE）以及生物可降解聚酯聚对苯二甲酸己二酸丁二醇酯（PBAT）、聚己内酯（PCL）中的均匀有序分散，制得分散结构可控的纳米复合薄膜与纤维，实现了复合材料力学、电学以及阻隔性能的极限增强，并探究了复合材料在机械应变、温度、光照等外界刺激条件下的微观结构变化规律，最终构建出了一种具有自感知功能的聚合物纳米复合纤维器件。