Han Yubing, Wang Fang, Li Hongkai, Meng Erchao, Fang Shaoming, Zhao Ansha, Guo Dongjie
State Laboratory of Surface & Interface, Zhengzhou University of Light Industry Zhengzhou 450002 China
College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics Nanjing China 210016.
RSC Adv. 2019 Dec 20;9(72):42450-42458. doi: 10.1039/c9ra07488k. eCollection 2019 Dec 18.
This study provides a facile and effective strategy to fabricate sulfonic SiO nanocolloid (HSO-SiO) doped perfluorosulfonic acid (PFSA) films with enhanced water uptake and inner channel for high-performance and cost-effective ionic exchange polymer metal composite (IPMC) actuators. A commercial precursor of mercaptopropyl trimethoxysilane was hydrolyzed to form thiol functionalized SiO nanocolloids (SH-SiO, ∼25 nm in diameter), which were further oxidized into sulfonic SiO nanocolloids (HSO-SiO, ∼14 nm in diameter). Both SiO nanocolloids were used as additives to dope PFSA film for fabricating IPMC-used matrix films. Due to difference of compatibility, the SH-SiO nanocolloids take phase separation in the cocrystallization course, and aggregate into huge, regular spherical particles with a mean diameter of ∼690 μm; while the HSO-SiO nanocolloids are completely compatible with PFSA, forming a very homogeneous hybrid matrix film. Related physiochemical investigations by analytical tools revealed that, the resultant HSO-SiO hybrid film shows better IPMC-related properties compared to the SH-SiO hybrid film: 1.59 folds in water uptake, and 2.37 folds in ion exchanging capacity, thus contains an increased number of cations and possesses larger and better interconnected inner channels for IPMC bending. Consequently, the HSO-SiO hybrid IPMC actuator exhibits remarkably higher levels of actuation behaviours such as higher force output, higher displacement output, and longer stable working time, which could be used as a valuable artificial muscle for flexible actuators or displacement/vibration sensors at low cost.
本研究提供了一种简便有效的策略，用于制备掺杂磺酸化二氧化硅纳米胶体（HSO-SiO）的全氟磺酸（PFSA）薄膜，该薄膜具有增强的吸水性和内部通道，可用于高性能且经济高效的离子交换聚合物金属复合材料（IPMC）致动器。巯基丙基三甲氧基硅烷的商业前体被水解形成硫醇官能化的二氧化硅纳米胶体（SH-SiO，直径约25 nm），其进一步被氧化成磺酸化二氧化硅纳米胶体（HSO-SiO，直径约14 nm）。两种二氧化硅纳米胶体均用作添加剂来掺杂PFSA薄膜，以制备用于IPMC的基质薄膜。由于相容性的差异，SH-SiO纳米胶体在共结晶过程中发生相分离，并聚集成平均直径约为690μm的巨大、规则球形颗粒；而HSO-SiO纳米胶体与PFSA完全相容，形成非常均匀的混合基质薄膜。通过分析工具进行的相关物理化学研究表明，所得的HSO-SiO混合薄膜与SH-SiO混合薄膜相比，表现出更好的与IPMC相关的性能：吸水性提高了1.59倍，离子交换容量提高了2.37倍，因此含有更多的阳离子，并且拥有更大且相互连接更好的内部通道用于IPMC弯曲。因此，HSO-SiO混合IPMC致动器表现出显著更高水平的致动行为，如更高的力输出、更高的位移输出和更长的稳定工作时间，这可以低成本用作柔性致动器或位移/振动传感器的有价值的人造肌肉。
