面向高性能柔性电子的强韧、可修复和优异抗穿刺的氟化弹性体

There is usually a trade-off between high mechanical strength and dynamic self-healing because the mechanisms of these properties are mutually exclusive.Herein,we design and fabricate a fluorinated phenolic polyurethane(FPPU)elastomer based on octafluoro-4,4'-biphenol to overcome this challenge.This fluorine-based motif not only tunes interchain interactions throughπ-πstacking between aromatic rings and free-volume among polymer chains but also improves the reversibility of phenol-carbamate bonds via electron-withdrawing effect of fluorine atoms.The developed FPPU elastomer shows the highest recorded puncture energy(648.0 m J),high tensile strength(27.0 MPa),as well as excellent selfhealing efficiency(92.3%),along with low surface energy(50.9 MJ m^(-2)),notch-insensitivity,and reprocessability compared with non-fluorinated counterpart biphenolic polyurethane(BPPU)elastomer.Taking advantage of the above-mentioned merits of FPPU elastomer,we prepare an anti-fouling triboelectric nanogenerator(TENG)with a self-healable,and reprocessable elastic substrate.Benefiting from stronger electron affinity of fluorine atoms than hydrogen atoms,this electronic device exhibits ultrahigh peak open-circuit voltage of 302.3 V compared to the TENG fabricated from BPPU elastomer.Furthermore,a healable and stretchable conductive composite is prepared.This research provides a distinct and general pathway toward constructing high-performance elastomers and will enable a series of new applications.

一种具有优良自愈合性和再加工性的富氟聚酚氨酯弹性体及其在可穿戴电子领域的应用

具有共价适应性网络的聚氨酯弹性体(PU-CANs)因其具有再加工性、自适应性和自愈合性而引起了人们的广泛关注.然而氨基甲酸酯的键能通常较高,在低温下实现其优异的动态性能仍然是一项艰巨的挑战.针对以上问题,基于动态性能可调范围广的酚氨基甲酸酯键,我们成功设计并制备了一种具有CANs的氟化聚酚氨酯弹性体(FPPU),系统地研究了氟原子对弹性体力学性能、热学性能、可再加工性、自愈性、表面自由能及疏水性的影响.和非氟化的聚酚氨酯弹性体(APPU)相比,FPPU表现出缺口不敏感性、自愈合效率高(98%)、动态解离温度低(60℃)、优异的可再加工性和低表面能(62 MJ m^(-2)).基于上述优点,FPPU被选为弹性基底,用于组装自供电的摩擦纳米发电机(TENG).该TENG具有优良的电输出性能,开路电压的峰值为103 V,短路电流的峰值为4.7μA,短路电荷的峰值为43 nC.此外,TENG还具有良好的自清洁性和再加工性.更进一步地,基于FPPU构建了面向柔性电子器件的可拉伸和自愈合复合导体.