Affiliation:
1. The Center of Functional Materials for Working Fluids of Oil and Gas Field School of New Energy and Materials Southwest Petroleum University Chengdu 610500 China
2. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Chengdu 610500 China
Abstract
AbstractHumidity‐responsive materials hold broad application prospects in sensing, energy production, and other fields. Particularly, humidity‐sensitive, flexibility, and water resistance are pivotal factors in the development of optimized humidity‐responsive materials. In this study, hydrophobic linear polyurethane and hydrophilic 4‐vinylphenylboronic acid (4‐VPBA) form a semi‐intercross cross‐linking network. This copolymer of polyurethane exhibits excellent humidity‐sensitive, mechanical properties, and water resistance. Its maximum tensile strength and maximum elongation can reach 40.56 MPa and 543.47%, respectively. After being immersed in water at various temperatures for 15 days, it exhibited a swelling ratio of only 3.28% in water at 5 °C and 9.58% in water at 70 °C. While the presence of 4‐VPBA network imparts humidity‐sensitive, reversible, and multidirectional bending abilities, under the stimulus of water vapor, it can bend 43° within 1.4 s. The demonstrated material surpasses current bidirectional humidity actuators in actuating ability. Based on these characteristics, automatically opening waterproof umbrellas and windows, as well as bionic‐arms, crawling robots, and self‐propelled boats, are successfully developed.
Funder
National Natural Science Foundation of China
State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation
Fok Ying Tung Education Foundation