Fast near-infrared light responsive shape memory composites: Polydopamine nanospheres hybrid polynorbornene

Abstract In this work, polynorbornene (PNB) (plasticized by 50 phr microcrystalline wax) with excellent thermo-triggered shape memory properties was used as the matrix material, in which synthetic polydopamine (PDA) nanospheres were hybrided. Consequently, PNB/PDA composites presented ultrafast near-infrared (NIR) responsive shape memory performance due to PDA's light-to-heat conversion ability. The results showed that PNB/PDA composites hybrided with 1 wt% PDA reached 74 °C within 50 s under the irradiation of NIR (808 nm wavelength). NIR-triggered shape memory performance of the PNB/PDA composites increased with the rise of NIR output power. When light power was 2.5w/cm2, the sample can completely recover its original shape within 20 s. Therefore, PDA-hybrided PNB composites not only have good thermal-responsive shape memory performance, but also have excellent one triggered by NIR, which broaden PNB's responsive ways for shape memory.