Soft Materials Research Laboratory, Department of Materials Science and Engineering, University of California, Los Angeles, 420 Westwood Plaza, Los Angeles, CA, 90095, USA.
Macromol Rapid Commun. 2023 Aug;44(15):e2300160. doi: 10.1002/marc.202300160. Epub 2023 May 28.
Dielectric elastomers based on commercial acrylic dielectric elastomers (VHB adhesive films) are widely investigated for soft actuators due to their large electrically driven actuation strain and high work density. However, the VHB films require prestretching to overcome electromechanical instability, which adds fabrication complexity. In addition, their high viscoelasticity leads to a low response speed. Interpenetrated polymer networks (IPNs) are developed to lock the prestrain in VHB films, resulting in free-standing films that are capable of large-strain actuation. In this work, a prestrain-locked high-performance dielectric elastomer thin film (VHB-IPN-P) by introducing 1,6-hexanediol diacrylate to create an IPN in the VHB network and a plasticizer to enhance the actuation speed is reported. VHB-IPN-P based actuators exhibit stable actuation at 60% strain up to 10 Hz and reach a peak energy density of 102 J kg⁻ . In addition, a hybrid process is also developed for the fabrication of multilayer stacks of VHB-IPN-P with strong inter-layer bonding and structural integrity. Four-layer stacks fabricated preserve the strain and energy density of single-layer VHB-IPN-P films but with linearly scaled force and work output.
基于商业亚克力介电弹性体(VHB 胶膜)的介电弹性体因其具有较大的电致驱动应变和较高的能量密度而被广泛应用于软体驱动器。然而,VHB 薄膜需要预拉伸以克服机电不稳定性,这增加了制造的复杂性。此外,其高粘弹性导致响应速度较慢。互穿聚合物网络(IPN)被开发用于锁定 VHB 薄膜中的预应变,从而得到具有大应变致动能力的独立薄膜。在这项工作中,通过引入 1,6-己二醇二丙烯酸酯在 VHB 网络中形成互穿网络,并添加增塑剂以提高致动速度,从而制备出一种预应变锁定的高性能介电弹性体薄膜(VHB-IPN-P)。基于 VHB-IPN-P 的驱动器在 60%应变下可稳定工作,频率高达 10 Hz,并达到 102 J kg⁻¹ 的峰值能量密度。此外,还开发了一种混合工艺,用于制造具有强层间结合和结构完整性的多层 VHB-IPN-P 堆叠。四层堆叠保留了单层 VHB-IPN-P 薄膜的应变和能量密度,但力和功的输出呈线性比例增加。