纸基石墨烯复合膜的制备及其智能变形研究

Preparation and intelligent deformation of paper-based graphene polymer double-layer composite films

柔性智能驱动器能将外部能量转换为机械能输出,在人工肌肉、软体机器人等领域具有良好的应用前景。文章设计并制备了纸基石墨烯复合双层薄膜,并实现了其在外部光照或湿度变化刺激下的驱动变形。通过多次浸渍-干燥及还原的方法制备了具有良好柔韧特性的纸基石墨烯膜,并与聚丙烯薄膜组成双层复合薄膜驱动器。利用石墨烯的光热转换特性、纸张的吸湿膨胀特性及聚丙烯薄膜的热膨胀特性,实现了该薄膜驱动器在外部光照刺激下的快速弯曲大变形。通过利用纸张中的纤维排列的各向异性,进一步调控该驱动器的光致变形幅度。此外,该驱动器也能对湿度变化进行响应,在环境湿度的变化为10%时,驱动器可产生弯曲角度为41°的弯曲变形。这是由于纸张中纤维素纤维对于环境水分子的吸附以及解吸附从而导致纸张的膨胀或收缩而造成的。该智能驱动器具有光照/湿度的双刺激源响应特性,结合其较简单的制备方法,有望在折纸机器人、智能机械等应用领域发挥作用。

The flexible intelligent actuator can convert external energy into mechanical energy,and has good application prospects in the fields of artificial muscles and software robots.In this paper,a paper-based graphene composite bilayer film was designed and prepared,and the actuating deformation under the stimulation of external light or humidity changes was realized.The paper-based graphene films with good flexibility characteristics were prepared by multiple impregnation-drying and reduction methods,and combined with polypropylene films,a two-layer film actuator was formed.Using the photothermal conversion characteristics of graphene,the hygroscopic expansion characteristics of paper,and the thermal expansion characteristics of polypropylene,the rapid bending and large deformation of the actuator under external light stimulation was realized.The photoinduced deformation amplitude of the actuator was further regulated by utilizing the anisotropy of the fiber arrangement in the paper.In addition,the actuator could respond to the changes of humidity.When the change in ambient humidity was 10%,the actuator could produce a bending deformation with a bending angle of 41°.This is caused by the adsorption and desorption of cellulose fibers in the paper to environmental water molecules,which causes the paper to expand or contract.The smart actuator has dual stimuli source response characteristics,and with its simple preparation method,it is expected to play a role in applications such as origami robots and intelligent machines.