Supporting Information

Transcription

1 Supporting Information Multi-Response Shape Memory Nanocomposite with Reversible Cycle for Powerful Artificial Muscles Chi Chen a, Yangyuanchen Liu b, Ximin He c, Hua Li a, Yujie Chen* a, Ying Wei d, Yusen Zhao c, Yanfei Ma c, Zhen Chen a, Xu Zheng a, and Hezhou Liu* a a State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai , China. b University of Michigan-Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, Shanghai , China c Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles 90095, USA d College of Engineering and Applied Sciences, Nanjing University, Nanjing , China * Corresponding author address: yujiechen@sjtu.edu.cn (Y. Chen); hzhliu@sjtu.edu.cn (H. Liu).

2 Supplementary 1: Shape memory behavior and artificial muscle performance test L2 L1 Rf = 1 100% L1 L3 L0 Rr = 1 100% L0 (S1) (S2) Where L0 represents the initial length, L1 represents the deformation length at the room temperature, L2 represents the fixation length after partial elastic contraction, and L3 represents the final length after the recovery process (Figure S24). M g ( L - L ) W M Mload g ( L2 - L3) P = M t load 2 3 = (S3) Where Mload and M represent the mass of the load and deformation section of the sample, respectively. Meanwhile, g represents the acceleration of gravity, and its value is 9.8 N kg -1, while t represents the response time, which is obtained by a high-speed camera. (S4) Supplementary 2: Finite element analysis II(xx) = II 0 ee xxxx dd (S5) Based on Beer-Lambert s law, the resulting deformation was governed by incident light intensity II 0, molecular alignment coefficient (θθ: the angle between liquid crystal orientation and the incident light), and absorption length dd (dd = 1.6 μm). The photocompliance (PP = 1.7 cm 2 W -1 and PP = 0.7 cm 2 W -1 ) correlated the absorbed light II(xx) (xx is the position vector) and the induced strain εε llllllhtt : εε lliiiihtt (xx) = φφpp II(xx) cccccc 2 θθ + φφpp II(xx) ssssss 2 θθ, (S6)

3 Where φφ is the weight fraction of azobenzene (φφ = 0.5). This yielded the resulting stress σσ llllllhtt : σσ llllllhtt,yy = εε bbbbbbbbbbbbbb εε llllllhtt,yy CC 11 ssssss 2 θθ+cc 22 cccccc 2 θθ, (S7) Where CC 11 and CC 22 are elasticity moduli, respectively. In our case, CC 11 = EE = MPa, CC 22 = EE = Mpa. And the light-induced bending radius rr became: rr = φφxx 3 6II 0 PPPP 2dd+2ddee φφφφ dd +φφφφ+φφφφee φφφφ dd, (S8) For heat transient problem inside the sample, the variation of temperature could be described by CC vv kk ff 2 TT = HH(xx, yy), (S9) Where CC vv is the specific heat capacity per unit volume, kk ff is the thermal conductivity of the sample. CC vv = 229 J mol -1 K -1 and kk ff = 0.35 W mol -1 K -1 Moreover, the temperature-induced strain became: εε TT = LL(TT)/LL 0 1 (S10) Where LL is the length of the sample along the xx-direction, LL 0 is the length of the sample in the initial state (LL 0 = 20 mm in the simulaiton). The total strain yielded: εε tttttttttt = εε eeeeeeeeeeeeee + εε TT (S11) Supplementary schemes, figures, tables and movies

4 Scheme S1 Synthetic routes of (a) AZO-diOH, (b) AZO11, and (c) PU. Scheme S2 Preparation of (a) water-soluble Au-nanorods and (b) oil-soluble Aunanorods. Scheme S3 In-situ polymerization of the homogeneous and stable composite.

5 Figure S1 FTIR spectra of 4-ethoxyanilin, AZO-OH, and AZO-11 Figure S2 FTIR spectra of p-aba and AZO-diOH. Figure S3 1 H NMR spectrum of PU.

6 Figure S4 1 H NMR spectrum of AZO-OH. Figure S5 1 H NMR spectrum of AZO11. Figure S6 1 H NMR spectrum of AZO-diOH.

7 Figure S7 1 H NMR spectrum of PU. Figure S8 LC-MS results of AZO-OH.

8 Figure S9 LC-MS results of AZO11. Figure S10 LC-MS results of AZO-diOH. Figure S11 DLS curve of the gold nanorods solution. Figure S12 UV-vis absorption spectra of gold nanoparticles.

9 Figure S13 UV-vis absorption spectra of gold nanoparticles. Figure S14 TEM images of the gold nanorods in (a-c) water-based solution and (d-f) DMF.

10 Figure S15 SEM image of the surface and EDS analysis of the component of PCL- AZO11/Au (El for element, A.C. for apparent concentration). Figure S16 GPC curve of composite sample PU-5AZO11/Au(50PCL).

11 Figure S17 Tan Delta in DMA of samples PU-5AZO11 with different PCL content. Figure S18 DSC diagram of AZO11 in a heating-releasing cycle. Figure S19 DSC curves of PCL-diOH, PU(50PCL), and PU-5AZO11(50PCL) in a heating-releasing cycle.

12 Figure S20 DMA diagrams of composites with different AZO11 and Au content. Figure S21 Tan Delta in DMA of samples with different AZO11 content. Figure S22 POM images of liquid crystal enhanced composite PU- 5AZO11/Au(50PCL), recorded during the heating process and the cooling process.

13 Figure S23 (a) XRD patterns and (b) POM images of the composite PU/Au(50PCL) with different content of AZO11. Figure S24 Schematic diagram of the responsive performance test. Figure S25 Optical images and SEM images of re-writing performance of PU/Au(50PCL) with (a) 10.0wt%, (b) 7.5wt%, (c) 5.0wt% and (d) 2.5wt% AZO11. Table S1 Sample numbers with various proportions and properties of composites. Sample No. PCL [g] AZOdiOH [g] HDI [g] AZO11 [g] Au [g] T g [ o C] T m [ o C] T cp [ o C] E [MPa] σ B [MPa] ε B [%] PU(30PCL)

14 PU(40PCL) PU(50PCL) PU-5AZO11(50PCL) PU-10AZO11(50PCL) PU- 5AZO11/Au(50PCL) PU(60PCL) PU(70PCL) PU(100PCL) Table S2 Artificial muscle application test with varied load (the weight of clip is g and the effect of buoyancy has been taken into account in the calculation of work density). No. L 0[mm] L 2[mm] L 3[mm] M load[g] h[mm] T[ o C] M[g] Rr[%] W [kj kg -1 ] t[s] P [W kg -1 ] > > Movie S1 Shape recovery behavior induced by heat at 60 o C. The movie is shown with 1.0 speed. Movie S2 Shape memory performance at different temperatures. The movie is shown with 0.1 speed. Movie S3 Artificial muscle performance at room temperature and over critical point. The movie is shown with 1.0 speed. Movie S4 Artificial muscle performance over critical temperature with the varied load. The movie is shown with 1.0 speed.

15 Movie S5 Artificial muscle performance through ten cycles. The movie is shown with 0.1 speed. Movie S6 Re-writing performance induced by heat at 100 o C. The movie is shown with 2.0 speed. Movie S7 Photo response performance induced by UV at 365 nm with one end fixed. The movie is shown with 1.0 speed. Movie S8 Photo response performance induced by NIR at 800~900 nm with one end fixed. The movie is shown with 1.0 speed. Movie S9 Photo response performance fixed induced by UV at 365 nm with both ends fixed. The movie is shown with 1.0 speed. Movie S10 Photo response performance fixed induced by NIR at 800~900 nm with both ends fixed. The movie is shown with 1.0 speed.