Supporting Information

Transcription

1 Supporting Information Graphene-elastomer composites with segregated nanostructured network for liquid and strain sensing application Yong Lin, Xuchu Dong, Shuqi Liu, Song Chen, Yong Wei, Lan Liu* College of Materials Science and Engineering, Key Lab of Guangdong Province for High Property and Functional Macromolecular Materials, South China University of Technology, Guangzhou , P. R. China * Corresponding author. psliulan@scut.edu.cn Tel: S-1

2 Figure S1. SEM images of segregated S-NRGE-0.42 composites (a and b) and homogeneous H-NRGE-0.42 composites (c and d). Figure S2. Comparison of mechanical properties of S-NRGE and H-NRGE as a function of GE content. (a) Tensile strength, (b) Elongation at break. S-2

3 Figure S3. Photographs of illumination changes for segregated S-NRGE-0.63 composites during immersing-drying process. Figure S4. Schematic of microstructural development for the segregated S-NRGE composites during the immersing-drying process. S-3

4 Table S1 The experimental formula for preparation of NR composites. Samples Neat GE-0.21 GE-0.42 GE-0.63 GE-0.84 GE-1.66 GE-3.27 GE 0 α NRL ZnO SA MB CZ DM S OP-10 α parts per fifty parts of solid rubber. S-4

5 Table S2 The comparison of electrical percolation threshold (φ c ) and conductivity for elastomer-ge composites previously reported. Samples φ c Conductivity (S m -1 ) Ref. TPU a /GE 0.05 vol% ~ ENR b /GE 0.23 vol% ~ SBR/GE 0.39 vol% ~ NR/GE 0.21 vol% ~ SBR/GE 0.55 vol% ~ SBR/GE 1.76 vol% ~ NR/GE 0.62 vol% ~ S-NRGE 0.40 vol% ~10-6 a TPU: Thermoplastic polyurethane; b ENR: Epoxidized natural rubber. S-5

6 Table S3 Comparison of liquid sensing performance of polymer composites previously reported. Samples Responsivity Response time (s) Ref. TPU a /CB b 0~70 ~200 8 TPU/PP c /CB 0~ PLA d /MWNT e 0~2 120~ PC f /CNT g 0~2000 0~ PLA/MWNT 0~12 30~ NR/MWNT/RGO h 1- ~ NR/RGO@CNC i ~ ~ NR/CB/CNs j 40~ ~ H-NRGE S-NRGE S-NRGE S-NRGE a TPU: Thermoplastic polyurethane, b CB: Carbon black, c PP: Polypropylene, d Poly(Ɛ-caprolactone), e MWNT: Multiwalled carbon nanotubes, f PC: Polycarbonate, g CNT: Carbon nanotubes, h RGO: Reduced grapheme oxide, i CNs: Cellulose nanowhiskers. S-6

7 Table S4 Interaction parameters χ and characteristics of solvents and NR used in the present work. Substances Solubility parameter ((J/cm 3 ) 1/2, 25 C) Molar volume (cm 3 /mol, 25 C) Boiling point ( C) χ NR Xylene Toluene Petroleum ether ~ n-hexane Tetrahydrofuran Dichloromethane S-7

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