Zhejiang excellent shape memory polymer configuration fast response of TF / graphene composite material
May 5th, reporters learned that Zhejiang University ,, superb (Corporate Communication), Xu Zhen (Corporate Communication) team and the Marxist-Leninist (Corporate Communication) team and other partners to work together, breaking the speed of response problem. This work graphene airgel highly stretchable as a template to build structures polycaprolactone (polycaprolactone, PCL) thin films (2.5-60nm) made of a shape memory network in its interior. Wherein the graphene nanonetwork energy conversion and energy as a quick injection channel, PCL nanonetwork energy transfer and rapid deformation as the carrier. Such airgel nanocomposites having PCL / graphene interpenetrating network structure under electrical stimulation response time of 50 ms, the response speed of 175 ± 40 mm s-1, a maximum deformation of about 100%. A shape memory polymer can be modified in accordance with established procedures external stimulation, which makes it has a promising prospect in drivers, sensors, drug delivery and the like. Since the polymer material of low thermal conductivity itself, and the slow rate of movement of the chain, the response speed of the shape memory polymer material having a large gap remains other than shape memory material (e.g., a shape memory alloy). The work \”Millisecond Responseof Shape Memory Polymer Nanocomposite Aerogel Powered by Stretchable GrapheneFramework\” was published in ACS Nano. conventional shape memory polymer composite preparation method and use more conductive additives blended, resulting in thermal conduction from the conductive network to the SMP matrix generally micron. However, the thermal conductivity of polymer materials are generally low (such as polycaprolactone PC used herein, – 0.3 W mK-1), which leads to the response time of the conventional shape memory polymer blend generally second level and above. This study is a highly stretchable airgel as a template to build nanoscale polycaprolactone continuous layer on the surface thereof nanometers (2.5-60 nm), to reduce the heat transfer distance. This can stretch the Institute airgel used is based on the team\’s 2018 \”Highly Stretchable Carbon Aerogels\” work (Nat.Commun.2018, 9, 881) are expanded ( \”Nature Communications\” Zhejiang University Professor Gao Chao team developed full high tensile carbon airgel elastomer). Using graphene airgel as injection and rapid energy conversion skeleton SMP achieve rapid phase transition. Finally obtained millisecond response time (50 ms), ultra-light composite airgel material elongation of 100% or more. At the same time, the work in situ TEM sample rod Wang Hongtao Task Force Zhejiang University School of Aeronautics and Astronautics developed independently observed composite airgel basic unit – graphene / PCL composite sheet shape memory behavior under electrical stimulation. The airgel composite material of lightweight fast response has broad application prospects, may be designed for ultra fast fuses to protect the delicate circuits in the event of an overload, disconnection may be within 134 ms, the protective appliances. It also can be combined with an electromagnet, as the micro-oscillator. PhD Professor Gao Chao Guo is the first author of the paper, PhD professor of Marxism-Zheng Wen is the second author of the paper. Professor of Polymer Science Professor Ma Liehu aerospace Wang Hongtao School of Zhejiang University, Zhejiang University, provides strong support and cooperation guidance for the completion of this work. Paper was funded by the National Key R & D Program, National Natural Science Foundation of China and other related funds.