Pei Dandan, An Chuanbin, Zhao Bin, Ge Mengke, Wang Zhongli, Dong Weijia, Wang Cheng, Deng Yunfeng, Song Dongpo, Ma Zhe, Han Yang, Geng Yanhou
School of Materials Science and Engineering, and Tianjin Key Laboratory of Molecular Optoelectronic Science, Tianjin University, Tianjin 300072, China.
Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Fuzhou 350207, China.
ACS Appl Mater Interfaces. 2022 Jul 18. doi: 10.1021/acsami.2c07445.
Polymer semiconductors with large elastic recovery (ER) under high strain in thin film state are highly desirable for stretchable electronics. Here we report a type of stretchable semiconductor PU(DPP), by copolymerization of oligodiketopyrrolopyrrole-based conjugated block and hydrogenated polybutadiene flexible block via urethane linkage for intermolecular hydrogen bonding. By regulating block ratio, PU(DPP) with 35 wt % conjugated block exhibits high intrinsic ER > 80% under 175% strain (ε) in pseudo free-standing thin film state, comparable with commercial elastomers, and crack onset strain (COS) > 300% along with maximum hole mobility of 0.19 cm V s in organic thin film transistors to bring it to the best performing block copolymer-type stretchable semiconductors. Enhanced mobility is achieved using PU(DPP) as the binder for conjugated polymer PDPPT3. The 25 wt %-PDPPT3 blend displays mobility up to 1.28 cm V s along with COS ∼120%, and 10 wt %-PDPPT3 blend exhibits ER of 78% at ε = 150%, COS of ∼230%, modulus of 36.5 MPa, maximum mobility of 0.62 cm V s and no obvious degradation of mobility at ε = 150% after 100 cycles of strain. Moreover, the structural similarity enables the blend film uniform and stable microstructure against mechanical and thermal deformation. Notably, PU(DPP) and the blend are characterized by high mechanical performance similar to that of commercial elastomers in thin film state, and demonstrate their potential for high performance stretchable electronics.
对于可拉伸电子器件而言，非常需要在薄膜状态下高应变时具有大弹性回复率（ER）的聚合物半导体。在此，我们报道了一种可拉伸半导体PU（DPP），它是通过基于低聚二酮吡咯并吡咯的共轭嵌段与氢化聚丁二烯柔性嵌段经由脲烷键进行共聚以形成分子间氢键而制备的。通过调节嵌段比例，具有35 wt%共轭嵌段的PU（DPP）在伪独立薄膜状态下于175%应变（ε）时表现出>80%的高固有ER，与商用弹性体相当，并且裂纹起始应变（COS）>300%，同时在有机薄膜晶体管中的最大空穴迁移率为0.19 cm² V⁻¹ s⁻¹，使其成为性能最佳的嵌段共聚物型可拉伸半导体。使用PU（DPP）作为共轭聚合物PDPPT3的粘合剂可实现迁移率的提高。25 wt%-PDPPT3共混物的迁移率高达1.28 cm² V⁻¹ s⁻¹，同时COS约为120%，而10 wt%-PDPPT3共混物在ε = 150%时的ER为78%，COS约为230%，模量为36.5 MPa，最大迁移率为0.62 cm² V⁻¹ s⁻¹，并且在150%应变下经过100次循环后迁移率没有明显下降。此外，结构相似性使共混薄膜具有均匀且稳定的微观结构，能抵抗机械和热变形。值得注意的是，PU（DPP）及其共混物在薄膜状态下具有与商用弹性体相似的高机械性能，并展示了它们在高性能可拉伸电子器件方面的潜力。
