基于共聚诱导自组装方法的聚丙烯腈基碳材料的可控制备及其电容性能研究

Polyacrylonitrile (PAN) is an excellent precursor of carbon materials. Controlled synthesis of PAN nanomaterials is a promising method to produce carbon nanomaterials with designed structure, which is conducive to prepare supercapacitor electrode with high performance. Polymerization-induced self-assembly (PISA) is a powerful tool for preparing polymeric nanomaterials with multiple morphologies. It offers many advantages over traditional self-assembly, such as one-pot, uniform morphologies and high solid content. However, the PISA of PAN is different to be performed because of their poor compatibility. Styrene（St）is introduced here as comonomer to solve this problem. In this proposal, we will develop a new method to prepare nanostructured carbons based on copolymerization-induced self-assembly of AN and St, and the route of “polymeric nanomaterials-carbon nanomaterials- capacitance performance” will be used here. Firstly, P4VP-b-(PAN-co-PS) nanomaterials with multiple morphologies will be obtained by copolymerization-induced self-assembly, and four factors in PISA are investigated to establish regularities of morphologies. Then, carbonization of polymeric precursors will be carried out to obtain carbon nanomaterials, and their microstructure will be discussed as well. Finally, their capacitance performance will be systematically studied, and the relationship between capacitive performance and nanostructure will be built. This project is expected to develop PISA in the formation of carbon nano-objects with more complex nanostructure and will provide an experimental and theoretical basis for further design and preparation of various nanosturetured carbons.

聚丙烯腈（PAN）是一种优异的碳材料前驱体，对其可控制备有望实现碳材料结构的精确调控，对制备高性能超级电容器电极材料具有重要的意义。聚合诱导自组装（PISA）方法简单高效，在聚合物纳米材料形貌调控方面具有明显的优势。但PAN体系相容性差，PISA难以进行，本项目设计了共聚策略，采用共聚诱导自组装方法实现其形貌调控。因此，项目拟采用 “PAN纳米材料制备-碳材料制备-电容性能研究”路线，以St和AN为共聚单体，利用共聚诱导自组装方法制备各种形貌的P4VP-b-(PAN-co-PS)纳米材料，通过单因素实验建立形貌调控规律；并以该PAN纳米材料为碳源，热解获得各种结构的碳材料，建立碳材料的结构调控规律；考察各种结构碳材料的电化学性能，阐明碳材料结构与电容性能的关系，获得碳基电极材料的设计优化原则。通过本项目的研究，为设计和可控制备高性能碳材料提供一种新的途径，推进碳材料在超级电容器领域的应用。

本项目通过发展丙烯腈（AN）体系的聚合诱导自组装（PISA）方法，可控制备多种形貌的PAN基纳米材料，并以此为前驱体热解制备碳材料，为碳材料结构的精确调控提供思路。PAN相容性差、分子间相互作用强，使其在聚合诱导自组装过程中单体转化率低、易团聚、形貌不可控。本项目一方面采用共聚策略，通过引入苯乙烯（St）单体和AN共聚，利用聚苯乙烯的插入减弱PAN的相互作用，提高其相容性；另一方面采用溶剂性质调控策略，在聚合介质中引入部分良溶剂来促进PAN链的溶剂化，提高运动能力，有利于PAN链的聚合增长和自组装。项目采用“PAN纳米材料制备-碳材料制备-电容性能研究”路线，主要研究内容如下：.（1）采用共聚策略发展AN体系的聚合诱导自组装，制备各种形貌的PAN基纳米材料，如球形、囊泡、针垫状、杨梅状、复合囊泡等。以PAN纳米材料为碳源，预氧化、碳化获得各种结构的碳材料。当电流密度为0.5 A·g-1时，其电容值为201 F·g-1。.（2）基于PISA方法，调控聚合体系的溶剂性质，制备均一规整的三维花团状结构PAN基纳米材料，碳化后具有良好的形貌保持性。当电流密度为0.5 A·g-1时，其电容值为124 F·g-1。.（3）静电纺丝方法制备PAN纳米纤维，碳化后得到多孔碳纤维，电流密度为0.5A·g-1时，电容值为180 F·g-1。.本项目为特定结构碳材料的制备提供可行的思路，对制备高性能超级电容器电极材料具有重要意义。