POLYIMIDE CELLULOSE NANOCRYSTAL

Transcription

1 SUPPORTING INFORMATION POLYIMIDE CELLULOSE NANOCRYSTAL COMPOSITE AEROGELS Baochau N. Nguyen, Elvis Cudjoe ±, Anna Douglas **, Daniel Schieman, Linda McCorkle, Mary Ann B. Meador *, and Stuart J. Rowan ± *, Ohio Aerospace Institute, Cedar Point Road, Cleveland, OH; NASA Glenn Research Center, Brookpark Road, Cleveland, OH, Case Western Reserve University, 2100 Adelbert Road, Cleveland, OH *To whom correspondence should be addressed - MAM and SJR) Ohio Aerospace Institute NASA Glenn Research Center ** NASA LERCIP Summer Student ± Case Western Reserve University Isolation of t-cncs (t-cnc-oh). Dry, clean, deproteinized tunicates mantles (10 g) were blended in 800 ml of DI water with a Waring blender until the mixture was pulpy. The mixture was transferred to a three neck 3 L round bottom flask. 200 ml of DI water was used to wash out the blender and added to the mixture, to which hydrochloric acid (316 ml) was slowly added to the suspension of fine cellulose pulp under continuous

2 stirring. After the addition of the acid, the mixture was refluxed and stirred for 1.5 h. The mixture was filtered over a fine fritted glass filter. The t-cncs were rinsed with DI water until neutral (ph of 6-7). 200 ml of DI water was added to the t-cncs, which were placed in a dialysis tube and dialyzed against water for 24 h and lyophilized. Yield by mass: 9.8g, 98%. Synthesis of Carboxylic acid functionalized t-cncs (t-cnc-cooh). The t-cnc-oh were oxidized using TEMPO, NaBr and NaClO. In short, dry hydrolyzed t-cnc-oh (5 g) were blended in 800 ml of DI water with a Waring blender until the mixture was pulpy. The mixture was transferred to a three neck 3 L round bottom flask. 200 ml of DI water was used to wash out the blender and added to the stirring mixture. To this mixture TEMPO (1 g) and NaBr (10 g) was added. After the reactants are fully dissolved/dispersed, 200, 100 or 50 wt. % of NaOCl (with respect to mass of t-cnc-oh in solution) was added to target a [COOH] of 1200 and 600 mmol/kg respectively. The ph was immediately adjusted to with 10 M NaOH and allowed to stir for 4 hours. NaCl (60 g) was then added and allowed to stir for a further 15 min after which the solution was filtered over a fine fritted filter. The solid was washed with 1 M NaCl and 0.1 M HCl, three times each and the resulting material was dispersed in 250 ml of DI water, placed in a dialysis tube and dialyzed against water for 24 h. Finally the material was lyophilized to yield 4.45g (89%) of the t-cnc-coohs as a white solid. The degree of functionalization on the surface of the t-cncs-coohs was determined via conductometric titration as previously described. Conductometric titrations of t-cnc-cooh. From the titration curves, the difference between the points where the trend line intersects represents the volume of 0.01 M NaOH

3 Conductivity ( S/cm) Conductivity ( S/cm) used (V 1 and V 2 ). The difference in volume is converted to mmol, which is divided by the weight of t-cnc-cooh (25mg) used in the conductometric titrations. The charge density is calculated using the equation below: Charge Density= M x (V 2-V 1 ) Wt.(kg) a) Volume (0.01M NaOH) b) Volume (0.01M NaOH) Figure S1. Conductometric titrations for t-cnc-cooh (a) 560mmol/kg and (b) 920mmol/kg.

4 (d) (c) 1 4 2,3,5 6 (b) (a) Figure S2. 13 C NMR spectra of (a) neat t-cnc-cooh, the ODA/t-CNC-COOH aerogel composite monoliths with (b) wt% and (c) 6.67 wt% d) the neat ODA-based PI aerogel. 0.1nm 50nm Figure S3. TEM image of wt% ODA-based PI aerogel

5 Pore volume, cm 3 /g Neat CNC 0 wt% CNC 6.67 wt% CNC 9.33 wt% CNC ODA Pore diameter, nm Figure S4. Graph of pore volume vs. pore diameter for neat CNC and ODA-based aerogel monoliths DMBZ ODA Porosity, % R 2 = stdv. = Figure S5. Graph of % porosity of aerogel monoliths vs. weight % of t-cnc-cooh.

6 Film density, g/cm DMBZ ODA R 2 = stdv. = Figure S6. Graph of aerogel film density vs. weight % of t-cnc-cooh. ODA (c) (b) (a) Figure S7. NMR spectra of ODA-based PI aerogel monoliths with 9.33 % t-cnc-cooh at (a) as fabricated, (b) 150 C, and (c) 200 C for 24h.

7 a) DMBZ as fabricated 150 o C 200 o C Surface area, m 2 /g b) Surface area, m 2 /g as fabricated: R 2 = , stdv. = o C: R 2 ODA as fabricated = , stdv. = o C: R 2 = , stdv. = o C 200 o C as fabricated: R 2 = , stdv. = o C : R 2 = , stdv. = o C : R 2 = , stdv/ = 3.09 Figure S8. Graphs of BET surface areas of (a) DMBZ-based (b) ODA-based aerogel composite monoliths at different aging conditions.

8 a) b) c) d) e) f) g) h) Figure S9. SEM of polyimide aerogels from the study after aging at 150 C at high and low magnification, respectively: a) and b) DMBZ-based aerogels with 0 wt% CNC; c) and d) DMBZ-based aerogels with wt% CNC; e) and f) ODA-based aerogels with 0 wt% CNC; and g) and h) ODA-based aerogels with wt% CNC.

9 a) b) c) d) e) f) g) h) Figure S10. SEM of polyimide aerogels from the study after aging at 200 C at high and low magnification, respectively: a) and b) DMBZ-based aerogels with 0 wt% CNC; c) and d) DMBZ-based aerogels with wt% CNC; e) and f) ODA-based aerogels with 0 wt% CNC; and g) and h) ODA-based aerogels with wt% CNC.

10 Run # Diamine Type Weight loss, % (From 200 o C to 425 o C) BET,m 2 /g Shrinkage, % Density, g/cm 3 Porosity, % CNC charge density, mmol/kg Table S1. Properties of polyimide aerogels and polyimide aerogel composites 1 DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ ODA ODA ODA ODA ODA ODA ODA ODA ODA ODA ODA

11 Run # Diamine Type Compression modulus, MPa 10% strain Tensile modulus, MPa Elongagion, % 1 st cycle 2 nd cycle 3 rd cycle Table S2. Mechanical properties of polyimide aerogels and polyimide aerogel composites Stiffness at 25 o C, N/m (film) 1 DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ ODA ODA ODA 0 20 ODA 0 21 ODA ODA ODA ODA ODA ODA ODA

12 Run # Diamine Type Weight loss, % Shrinkage, % (during aging) Density, g/cm 3 BET, m 2 /g Weight loss, % Shrinkage, % (during aging) Density, g/cm 3 BET, m 2 /g Table S3. Isothermal properties of polyimide aerogels and polyimide aerogel composites at 150 C and 200 C for 24h. Aged at 150 o C for 24h (cylinder) Aged at 200 o C for 24h (cylinder) 1 DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ DMBZ ODA 0 18 ODA ODA ODA ODA ODA ODA ODA ODA ODA ODA