In this work,we demonstrate the microwave-assisted synthesis of naphthalene diimide-based polymers via three-component polymerization (TCP) of diynes,dialdehydes and dibenzylamine,and the applications of such polymers as cathode interfacial layers for polymer solar cells.The TCP of diynes (1a～1e),dialdehydes (2a～2b) and dibenzylamine catalyzed by InC13 could be performed smoothly under microwave irradiation in very short reaction time,yielding soluble polymers P1 ～P4 with high molecular weights.The chemical structures of these resulting polymers were confirmed by nuclear magnetic resonance spectroscopy.The thermal stability,photophysical and electrochemical properties of the resulting polymers were also investigated.Besides,the effects of chemical environment of amine groups on the resulting polymers'electrode modification capability and self-doping behavior were explored by conducting scanning Kelvin probe microscopy and electron paramagnetic resonance (EPR) spectroscopy studies,respectively.It was found that the chemical environment variation of amine groups,including the decreasing electron density of the nitrogen atoms in alkylamine and the enhancing steric hindrance around the nitrogen atoms from substituent groups,can substantially influence the electrode modification capability and self-doping behavior of the resulting polymers.Moreover,quantum chemistry calculation was also conducted to qualitatively illuminate the essential distinction in chemical environment of different amine groups.It was found that the negative atomic dipole moment corrected Hirshfeld (ADCH) charge of nitrogen atoms in side chains was significantly larger than the ADCH charges of nitrogen atoms in main chains.Among all the resulting polymers,P1 can be easily dissolved in alcohol due to its amino functionalized side chain groups and thus was utilized as the cathode interlayer for polymer solar cells.The device with P1 as the cathode interlayer and PTB7-Th:PC71BM as the photoactive layer exhibits a high power conversion efficiency of 9.34％,which is much better than that of the control device without such cathode interlayer.All these results provide a guideline for the material design of amino-functionalized polymers for the optoelectronic devices.And it was also shown that the multicomponent polymerization (MCP) is an effective strategy for the synthesis of functional polymers,and may trigger broad research interests in developing effective polymerization approaches toward multi-functional polymer materials.%通过微波辅助炔、醛、胺三组分一锅法聚合反应合成了一系列基于萘并二酰亚胺的聚合物P1～P4,并通过核磁表征确认其结构.目标聚合物的光物理与电化学性能研究表明,由于聚合物主链共轭被打断,聚合物的吸收和能级主要由其重复单元决定.通过开尔文探针与电子顺磁共振谱研究了聚合物侧链与主链胺基不同的化学环境对其电极功函调节以及自掺杂行为的影响.发现由于主链胺基与苄基、炔丙基相连,胺基氮的电子云密度显著降低,导致聚合物形成界面偶极能力减弱,从而使其电极功函调节能力与自掺杂强度都大大降低.所有聚合物中P1具有良好的醇溶性,可被用于聚合物太阳电池的阴极界面层.以PTB7-Th:PC71BM为活性层,P1为阴极界面层的聚合物太阳电池器件的光电转换效率达到9.34％.
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