Laboratory of Stimuli-Responsive Functional Materials & Devices (SFD), Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Den Dolech 2, 5612 AZ, Eindhoven, The Netherlands.
Supramolecular Polymer Chemistry Group, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Den Dolech 2, 5612 AZ, Eindhoven, The Netherlands.
Macromol Rapid Commun. 2021 Jul;42(14):e2100157. doi: 10.1002/marc.202100157. Epub 2021 May 3.
Untethered, light-responsive, high-stress-generating actuators based on widely-used commercial polymers are appealing for applications in soft robotics. However, the construction of actuators that are stable and reversibly responsive to low-intensity ultraviolet, visible, and infrared lights remains challenging. Here, transparent, stress-generating actuators are reported based on ultradrawn, ultrahigh molecular weight polyethylene films. The composite films have different draw ratios (30, 70, and 100) and contain a small amount of graphene in combination with ultraviolet and near-infrared-absorbing dyes. The composite actuators respond rapidly (t < 0.8 s) to different wavelengths of light (i.e., 780, 455, and 365 nm). A maximum photoinduced stress of 35 MPa is achieved at a draw ratio of 70 under near-infrared light irradiation. The photoinduced stress increases linearly with the light intensity, indicating the transfer of light into thermally induced mechanical contraction. Moreover, the addition of additives lead to a reduction in the plastic creep rate of the drawn films compared to their nonmodified counterparts.
基于广泛使用的商业聚合物的无束缚、光响应、高应力产生的驱动器对于软机器人应用非常有吸引力。然而，构建对低强度紫外线、可见光和红外线稳定且可重复响应的驱动器仍然具有挑战性。在这里，报道了基于超拉伸超高分子量聚乙烯薄膜的透明、产生应力的驱动器。复合薄膜具有不同的拉伸比（30、70 和 100），并结合了少量石墨烯以及紫外线和近红外线吸收染料。复合驱动器可以快速响应（t < 0.8 s）不同波长的光（即 780、455 和 365 nm）。在近红外光照射下，拉伸比为 70 时可达到 35 MPa 的最大光致应力。光致应力随光强度线性增加，表明光能转化为热诱导的机械收缩。此外，与未改性的薄膜相比，添加剂的加入降低了拉伸薄膜的塑性蠕变速率。
