Simultaneous Enhancement of Stretchability, Strength, and Mobility in Ultrahigh-Molecular-Weight Poly(indacenodithiophene-co-benzothiadiazole)

• DOI: 10.1021/acs.macromol.1c01513
• Publication Date: 2021-10-21T20:51:53Z
• Authors: Bin Zhao; Dandan Pei; Yu Jiang; Zhongli Wang; Chuanbin An; Yunfeng Deng; Zhe Ma; Yang Han; Yanhou Geng
• Keywords: Chemical Sciences not elsewhere classified; stretchable electronics; 100 cycles; charge transport along; Biophysics; w </ sub; 7 mpa; 02 engineering and technology; Biochemistry; 333; weight poly; free morphology; higher extent; conjugated polymers; dependent study confirms; exhibiting enhanced elasticity; 2 </ sup; >< sub; Computational Biology; larger range; molecular weight; co </; >- benzothiadiazole; charge transport properties; elastic recovery; 6 kg mol; detailed molecular weight; charge mobility; chain entanglement; simultaneously enhance; 63 cm; simultaneous enhancement; indacenodithiophene -<; 0210 nano-technology; Physical Sciences not elsewhere classified; Biotechnology

To simultaneously obtain outstanding stretchability, strength, and charge mobility of conjugated polymers (CPs) has remained a challenge for the field of stretchable electronics to date. Herein, we propose a strategy of increasing the molecular weight of a near-amorphous CP poly­(indacenodithiophene- co -benzothiadiazole) (IDT-BT) to an ultrahigh level to overcome the trade-off. Detailed molecular weight-dependent study confirms that increasing the molecular weight can simultaneously enhance the mechanical and charge transport properties of IDT-BT, owing to the higher extent of chain entanglement and a larger range of charge transport along the backbone. Ultrahigh-molecular-weight (1049.6 kg mol –1 , weight average) IDT-BT exhibited the highest mobility of 2.63 cm 2 V –1 s –1 , modulus of 1126.7 MPa, elastic recovery >80%, crack onset strain >100%, fracture strain ≥20%, and a crack-free morphology after 100 cycles of strain. To the best of our knowledge, the ultrahigh- M w IDT-BT outperforms previously reported stretchable CPs by exhibiting enhanced elasticity, strength, and charge mobility at the same time.