Transfer of Chirality from Molecule to Phase in Self-assembled Chiral Block Copolymers

Transcription

1 Transfer of Chirality from Molecule to Phase in Self-assembled Chiral Block Copolymers Rong-Ming Ho,* Ming-Chia Li, Shih-Chieh Lin, Hsiao-Fang Wang, Yu-Der Lee, Hirokazu Hasegawa, and Edwin L. Thomas Supporting Information Figure S1 Figure S2 Figure S3 Figure S4 Figure S5 Figure S6 Figure S7 1 H NMR spectrum of hydroxy-terminated PS-perylene (M PS n =32,000 g/mol) 1 H NMR spectrum of PS-perylene-PLLA (f v PLLA =0.21) 1 H NMR spectrum of PS-perylene-PDLA (f v PDLA =0.19) 1 H NMR spectrum of PS-perylene-PLA (f v PLA =0.20) 1 H NMR spectrum of PS-perylene-PLLA (f v PLLA =0.35) 1 H NMR spectrum of PS-perylene-PDLA (f v PDLA =0.35) 3D correlation of GPC elution volume and in-line diode array UV-Vis spectra for (a) PS-perylene-PLLA (f PLLA v =0.35), (b) PS-PLLA (f PLLA v =0.35), and (c) PS-perylene- PDLA (f PDLA v =0.35) in THF solution. The concentration of solution is 0.5wt%. Figure S8 DSC heating thermograms of (a) PLLA, (b) PDLA and (c) PLA samples rapidly cooled from isotropic melt. The heating rate is 10 o C/min. Figure S9 DSC heating thermograms of (a) PS-PLLA, (b) PS-PDLA and (c) PS-PLA rapidly cooled from isotropic melt. The heating rate is 10 o C/min. Figure S10 CD and corresponding UV-Vis absorption spectra of L-lactic acid, D-lactic acid and L,D-lactic acid in dilute AcCN solution. The concentration of solution is 0.1wt%. Figure S11 LD spectra of (a) lactic acids, (b) polylactide homopolymers and (c) polylactidecontaining block copolymers in dilute AcCN solution, respectively. The concentration of solution is 0.1wt%. Figure S12 VCD and corresponding FT-IR absorption spectra of L-lactic acid, D-lactic acid and S1

2 L,D-lactic acid in dilute CH 2 Cl 2 solution. The concentration of solution is 2wt%. Figure S13 Schematic illustration of left-handed and right-handed helices in 3D space (left column) and 2D projection (right column). Figure S14 1D SAXS profiles of PS-PLLA (left) and PS-PDLA (right) after removal of polylactide blocks by hydrolysis. Figure S15 TEM images (left) and corresponding 1D SAXS profiles (right) of PS/SiO 2 helical nanohybrids fabricated using the PS templates from (a) PS-PLLA and (b) PS-PDLA for sol-gel reaction, respectively. Figure S16 (a) and (d) TEM projections of PS/SiO2 helical nanohybrids, fabricated using templates from PS-PLLA and PS-PDLA, respectively. The sample thickness is about 100 nm. The dark spots are the gold nanoparticles used as fiducial markers for image tracing and alignment. Black line in (a) and (d) indicates the tilting axis which the sample was rotated between ±70 around. Red-dashed-line areas refer the range of the reconstructed volumes as presented in (b) and e, after binarization of the reconstructed volume; here the PS phase is dark. (c) and (f) 3D visualization of the color domains in (b) and (e) after binarization and segmentation, respectively. Figure S17 Figure S18 Illustration of the geometric factors of helical phase from the self-assembly of BCPs*. (a) Concentration-dependent CD and (b) the corresponding UV-Vis absorption spectra of PS-perylene-PLLA (f PLLA v = 0.21) in CH 2 Cl 2 solution Figure S19 Temperature-dependent CD and corresponding UV-Vis absorption spectra of PSperylene-PLLA (f PLLA v =0.21) in toluene solution. The concentration of solution is 3wt%. Figure S20 Concentration-dependent VCD spectra of PS-perylene-PLLA (f PLLA v =0.35) and PSperylene-PDLA (f v PDLA =0.35) in toluene solution. Figure S21 VCD spectra of PS-perylene-PLLA (f v PLLA =0.35) and PS-perylene-PDLA (f v PDLA =0.35) in CH 2 Cl 2 (2wt%) and in toluene tolution (2wt%). S2

3 S1. Characterization of BCP with polylactide-containing BCPs with a perylene bisimide junction Figure S1. 1 H NMR spectrum of hydroxy-terminated PS-perylene (M n PS =32,000 g/mol) S3

4 Figure S2. 1 H NMR spectrum of PS-perylene-PLLA (f PLLA v =0.21) S4

5 Figure S3. 1 H NMR spectrum of PS-perylene-PDLA (f PDLA v =0.19) S5

6 Figure S4. 1 H NMR spectrum of PS-perylene-PLA (f PLA v =0.20) S6

7 Figure S5. 1 H NMR spectrum of PS-perylene-PLLA (f PLLA v =0.35) S7

8 Figure S6. 1 H NMR spectrum of PS-perylene-PDLA (f PDLA v =0.35) S8

9 a b c Figure S7. 3D correlation of GPC elution volume and in-line diode array UV-Vis spectra for (a) PS-perylene-PLLA (f PLLA v =0.35), (b) PS-PLLA (f PLLA v =0.35) and (c) PS-perylene-PDLA (f PDLA v =0.35) in THF solution. The concentration of solution is 0.5wt%. S9

10 S2. Characterization of polylactide homopolymers and polylactide-containing block copolymers. S2-1. Thermal properties The thermal behaviors of polylactide homopolymers (PLLA and PDLA and PLA) and polylactide-containing block copolymers (PS-PLLA, PS-PDLA and PS-PLA) were examined by DSC. As shown in Figure S8, the glass transition temperature (T g ) of PLLA and PDLA homopolymers can be found at 54 o C, and the maximum crystallization temperature (T c ) is at 89 o C for PLLA and 92 o C for PDLA. At higher temperature region, there are double melting temperatures (T m ) observed in both homopolymers: 160 o C and 169 o C for PLLA, and 161 o C and 169 o C for PDLA, which is attributed to the reorganization behavior during heating. In contrast to the crystallization of helical homopolymers due to their regular chiral configuration, racemic homopolymer (PLA) only exhibits T g at 39 o C, and no melting can be identified due to its irregular configuration (Figure S8c). In contrast to polylactide homopolymers, polylactide-containing BCPs* exhibit different crystallization behavior due to the confinement effect of vitrified PS at which the T g of PS block in PS-PLLA and PS-PDLA is approximately 100 o C and above the maximum crystallization temperature of chiral polylactides so that the DSC thermograms of PS- S10

11 PLLA and PS-PDLA exhibit only T g of each constituent blocks but no significant exothermic peak from the crystallization of chiral polylactides can be identified during heating (Figure S9a, b) 1, 2. Consistently, the T g of polylactide block in PS- PLLA is 54 o C and that in PS-PDLA is 55 o C. As a result, only a small endothermic peak appearing at 166 o C for PS-PLLA and 169 o C for PS-PDLA can be found because of the occurrence of crystallization at temperature over the T g of PS block. By contrast, the DSC thermogram of PS-PLA only shows two glass transitions at 46 o C for PLA block and approximately 100 o C for PS block (Supplementary Figure S9c). The lower T g of PLA than that of PLLA and PDLA is attributed to the irregular configuration of PLA so as to result in higher flexibility than that of PLLA and PDLA 3, 4. S11

12 Figure S8. DSC heating thermograms of (a) PLLA, (b) PDLA and (c) PLA samples rapidly cooled from isotropic melt. The heating rate is 10 o C/min. S12

13 Figure S9. DSC heating thermograms of (a) PS-PLLA, (b) PS-PDLA and (c) PS-PLA rapidly cooled from isotropic melt. The heating rate is 10 o C/min. S13

14 Figure S10. CD and corresponding UV-Vis absorption spectra of L-lactic acid, D- lactic acid and L,D-lactic acid in dilute AcCN solution. The concentration of solution is 0.1wt%. S14

15 S2-2. Anisotropic effect on CD spectrum Figure S11. LD spectra of (a) lactic acids, (b) polylactide homopolymers and (c) polylactide-containing block copolymers in dilute AcCN solution, respectively. The concentration of solution is 0.1wt%. S15

16 Figure S12. VCD and corresponding FT-IR absorption spectra of L-lactic acid, D- lactic acid and L,D-lactic acid in dilute CH 2 Cl 2 solution. The concentration of solution is 2wt%. S16

17 S2-3. 3D TEM. It is noted that 2D TEM imaging is the result of 3D object projection. Considering the projection of the microsection for TEM observation, the thickness is approximately equivalent to the geometric factors of the self-assembled helix. It is highly possible to cause the artificial effect for projection imaging. Consequently, the 2D TEM projections might not be suitable for the identification of the handedness of the helix (see below for reasons). As shown in Figure S13, full-sized left-handed and righthanded helices exhibit the same 2D projected images in 2D projection. Moreover, while the helix was cut in half by microsectioning, the left-handed helix might give both right-handed and left-handed 2D projections, depending on which part of the helix examined. Similarly, the right-handed helix might give the left-handed and right-handed 2D projections. Obviously, it is impractical to use 2D TEM projection for the determination of the helical handedness because of the artificial effect from 2D projection for 3D object. Consequently, the electron tomography should be carried out for the determination of the handedness of the H* phase. S17

18 Figure S13. Schematic illustration of left-handed and right-handed helices in 3D space (left column) and 2D projection (right column). S18

19 S2-4. Enhancement of mass-thickness contrast for image reconstruction. As shown in Figure S14, the reflection peaks of the 1D SAXS profiles of PS- PLLA and PS-PDLA after hydrolysis occur at q* ratios of 1: 3: 4: 7: 13: 27 for both samples. The scattering results are similar to the PS-PLLA and PS-PDLA before hydrolysis (Figures 3B, D), indicating the preservation of nanostructured texture after hydrolysis. Also, significant enhancement on the scattering contrast gives the appearance of high-order reflections so as to further confirm the completion of polylactide hydrolysis (see Experimental Section in detail). Figures 15a, b show the TEM projection images of unstained PS/SiO 2 microsections (approximately 100 nm in thickness) fabricated using the PS templates from PS-PLLA and PS-PDLA for solgel reaction, respectively. In contrast to Figures 3A, 3C, similar helical projection images can be observed but the contrast is inversed (i.e., bright matrix and dark minor domains), reflecting that the polylactides are degenerated completely by hydrolysis and the SiO 2 is loaded successfully by templated sol-gel process. The corresponding 1D SAXS profiles of the PS/SiO 2 helical nanohybrids further demonstrate the formation of large-scale nanohybrids from templating at which the reflection peaks occur at q* ratios of 1: 3: 9: 13 (Figure 15), similar to the results in Figure 3. Nevertheless, there is a significant amount of deformation after sol-gel reaction; the interspacing is reduced to approximately 44.5 nm for the PS/SiO 2 helical nanohybrids S19

20 as compared to the original value of 50.3 nm for the PS template from PS-PDLA. In comparison with the domain sizes of the polylactide helices and SiO 2 helices from TEM observations, no significant change in dimension can be found. We speculate that the change in the interspacing (about 12% reduction) is caused by the relaxation of helical textures resulting from the swelling of the PS matrix by the sol so as to lead the dimensional change in the interspacing after the formation of dry gel. Accordingly, it is expected that the decrease in the interspacing could associate with the increase of the helical pitch length so as to maintain the mean density of PS template. Figures S16a, d show wave-like projection images of the PS/SiO 2 helical nanohybrids fabricated by using the templates from PS-PLLA and PS-PDLA for solgel reaction, respectively. Figures S16b, e are the side-view images and the crosssection slices after binarization of the reconstructed volumes (red-dashed-line areas in Figures S16a, d) at which the PS phase is dark, confirming the hexagonally packed character of the helical nanostructures. Subsequently, 3D visualization after binarization and segmentation for the helical nanostructures was performed. As shown in Figures S16c, f, left- and right-handed SiO 2 nanohelices can be clearly identified. S20

21 Figure S14. 1D SAXS profiles of PS-PLLA (left) and PS-PDLA (right) after removal of polylactide blocks by hydrolysis. S21

22 Figure 15. TEM images (left) and corresponding 1D SAXS profiles (right) of PS/SiO 2 helical nanohybrids fabricated using the PS templates from (a) PS-PLLA and (b) PS-PDLA for sol-gel reaction, respectively. S22

23 Figure S16. (a) and (d) TEM projections of PS/SiO2 helical nanohybrids, fabricated using templates from PS-PLLA and PS-PDLA, respectively. The sample thickness is about 100 nm. The dark spots are the gold nanoparticles used as fiducial markers for image tracing and alignment. Black line in (a) and (d) indicates the tilting axis which the sample was rotated between ±70 around. Red-dashed-line areas refer the range of the reconstructed volumes as presented in (b) and e, after binarization of the reconstructed volume; here the PS phase is dark. (c) and (f) 3D visualization of the color domains in (b) and (e) after binarization and segmentation, respectively. S23

24 Figure S17. Illustration of the geometric factors of helical phase from the selfassembly of BCPs*. S24

25 S3. Characterization of polylactide-containing block copolymers with a perylene junction. S3-1. UV-Vis absorption spectra of Polylactide-containing Block Copolymers with a perylene junction. As shown in Figures 6, 9 and S18b, the absorption spectra reveal the characteristic transitions for the perylene moiety as the chemical junction of polylactide-containing BCP; S 0 -S 1 transition at 518 (ν=0 ν =0), 484 (ν=0 ν =1) and 454 nm (ν=0 ν =2) where ν and ν are quantum vibrational numbers of the ground and excited states, respectively. S25

26 Figure S18. (a) Concentration-dependent CD and (b) the corresponding UV-Vis absorption spectra of PS-perylene-PLLA (f PLLA v = 0.21) in CH 2 Cl 2 solution, respectively. S26

27 Figure S19. Temperature-dependent CD and corresponding UV-Vis absorption spectra of PS-perylene-PLLA (f PLLA v =0.21) in toluene solution. The concentration of solution is 3wt%. S27

28 wt% PS-perylene-PLLA 1.0wt% PS-perylene-PLLA 0.5wt% PS-perylene-PLLA 0.1wt% PS-perylene-PLLA Abs wt% PS-perylene-PDLA 0.5wt% PS-perylene-PDLA 1.0wt% PS-perylene-PDLA 2.0wt% PS-perylene-PDLA Wavenumber (cm -1 ) Figure S20. Concentration-dependent VCD spectra of PS-perylene-PLLA (f PLLA v =0.35) and PS-perylene-PDLA (f PDLA v =0.35) in toluene solution. S28

29 Αbs Abs PS-perylene-PDLA in CH 2 Cl 2 PS-perylene-PLLA in CH 2 Cl 2 PS-perylene-PDLA in Toluene PS-perylene-PLLA in Toluene Wavenumber (cm -1 ) Figure S21. VCD spectra of PS-perylene-PLLA (f PLLA v =0.35) and PS-perylene- PDLA (f PDLA v =0.35) in CH 2 Cl 2 (2wt%) and in toluene solution (2wt%). S29

30 References: 1. Chiang, Y.-W.; Ho, R.-M.; Ko, B.-T.; Lin, C.-C. Angew. Chem. Int. Ed. 2005, 44, Chiang, Y.-W.; Ho, R.-M.; Thomas, E. L.; Burger, C.; Hsiao, B. S. Adv. Funct. Mater., 2009, 19, Urayama, H.; Moon, S.-II; Kimura, Y. Macromol. Mater. Eng. 2003, 288, Pan, P.; Liang, Z.; Zhu, B.; Dong, T.; Inoue, Y. Macromolecules 2009, 42, S30