聚苯乙烯-b-聚丙烯酸模板剂成核段长度对聚苯胺尺寸及性能的影响

Influence of the Core Forming Block Length ofPolystyrene- b -Poly(acrylic acid) Template onthe Size and Properties of Polyaniline

以两亲性嵌段共聚物为模板是构筑导电聚合物纳米结构并对其形貌尺寸进行调控的有效方法之一。嵌段共聚物成核段长度的变化对其胶束化行为有显著影响,进而也会改变受限于其胶束形貌的导电聚合物的形貌尺寸。形貌尺寸的变化必然导致导电聚合物电化学性能变化。本文欲通过嵌段共聚物模板诱导实现对聚苯胺(PANI)形貌尺寸的调控并使其电化学性能得到优化,采用可逆加成-断裂链转移自由基聚合(RAFT)法成功合成了嵌段共聚物聚苯乙烯-b-聚丙烯酸PS x-b-PAA 70(x=38、64、101)并以其胶束为“模板”制备了窄相对分子质量分布的PANI。在成核段(PS)长度较短时,模板诱导形成的棒状PANI颗粒,直径为100~200 nm。当x=101时PANI呈现空间网状结构,其放电比容量高于其它样品,在电流密度为1 A/g时,其放电比容量可达386.71 F/g。

Use of amphiphilic block copolymers as templates is one of the effective methods to construct conducting polymer nanostructures and adjust their morphologies and sizes.The change of the length of core-forming block has a significant effect on their micellization behavior,and then changes the morphology and size of conducting polymers limited by their micelle morphology.The change of morphology and size will inevitably lead to the change of electrochemical properties of conducting polymers.In this paper,the morphology and size of polyaniline(PANI)were controlled and its electrochemical performance was optimized by block copolymer template induction.Polystyrene-b-poly(acrylic acid)(PS x-b-PAA 70,x=38,64,101)was successfully synthesized by reversible addition-fragmentation chain transfer radical polymerization(RAFT)and its self-assembled micelles were used as templates to prepare PANI.When the length of core forming block is shorter,the PANI shows rod-like particles with diameters 100~200 nm.When x=101,PANI presents spatial network structure and has the highest discharge specific capacitance.When the current density is 1 A/g,its discharge specific capacity can reach 386.71 F/g.