1. Structural Studies of Proton-Conducting Fluorous Block Copolymer Membranes Barbara Frisken – SFU Physics Laurant Rubatat - University of Fribourg Ken Shi – NRC IFCI Steven Holdcroft – SFU Chemistry and NRC IFCI Olivier Diat – CEA Grenoble

2. Two Series of Diblock Copolymers Series #1 – Variable Sulfonation 22% 32% 40% Sulfonation Rate 1B 1A 1C A B Poly(Vinylidene DiFluoride-co-Hexafluoropropylene) P(VDF-co-HFP) Sulfonated PolyStyrene sPS 17,900 g/mol 8,000 g/mol

3. 9 12.5 18 2B 2A 2C 25,000 g/mol Degree of polymerization A B Poly(Vinylidene DiFluoride-co-Hexafluoropropylene) P(VDF-co-HFP) Sulfonated PolyStyrene sPS 1000-2000 g/mol Two Series of Diblock Copolymers Series #2 – Variable sPS Length

4. Conductivity and TEM Z. Ken Shi (2A) (2B) (1B) (1A) (2C) (1C) Nafion

5. Conductivity and TEM Z. Ken Shi (2A) (2B) (1B) (1A) (2C) (1C) Nafion 1A 1B 1C 2B 2C

6. SANS Studies The scattered intensity is proportional to the product of a structure factor S(q) and a form factor P(q): where P(q) describes the shape of the scattering objects and S(q) describes the spatial distribution of these objects. Neutron Beam Sample Detector 

7. Peak #1 Peak #2 Series #1 – Two Peaks Peak #1  400 Å Peak #2  40 Å Slight shift of the peaks to small angles  size increasing with IEC. Neutron Scattering Spectra – in D 2 O Series #2 – Two Peaks Peak #1  400 Å Peak #2  40 Å Peak #1 is less sharp  less ordered Peak #2 Peak #1 Series #1 – Partially SulfonatedSeries #2 – Variable Length

8. Contrast Variation Peak #1 Peak #2 Membrane 2B Peak #1 Membrane 1C Peak #2 Series #1 – Partially SulfonatedSeries #2 – Variable Length

9. Contrast Variation Series #1 Peak #1 Peak #2 Binary System Structure enhanced or diminished Ternary System Match core Match corona Membrane 1C

10. Spectra Divisions Membrane 1C t s r Core-shell disk form factor R >> t + 2s => Lamellar

11. Series #1 – Partially sulfonated PVDF PS Hydrated sPS 25 Å 165 Å 280 Å 180 Å 220 Å 30 Å170 Å 28 Å 180 Å Solvent pool 1B 1A 1C  p = 56 %  p = 30 %  p = 25 %

12. Series #2 – Fully sulfonated Contrast Variation Peak #1 Peak #2 Membrane 2B Binary System Structure enhanced or diminished

13. Small Length Scale Structure Modified hard-sphere model Yarusso and Cooper, Macromolecules 1983 Spherical ionic aggregates within PS matrix Hydrated sPS domain Increasing sulfonation from 22-100% leads to a decrease in the size of the barrier between ionic groups – consistent with improved conductivity.

14. Series #1 Series #2 40 Å 400 Å Fluorous domains and Hydrated sPS domains Solvent pools in a PS matrix

15. f  Volume fraction of A block (from data)  N  Interaction between blocks (not known) Series #1 Series #2 Series #1 shows lamellar structure Series #2 shows phase separation, but no long range order Compare to diblock copolymer theory Matsen and Bates, Macromolecules 1996 Q Im3m spheres H cylinders Q Ia3d bi-continuous L lamellar

16. Conductivity and SANS (2A) (2B) (1B) (1A) (2C) (1C) Nafion Large scale structure is more ordered in Series #1 sPS domains are similar Large scale structure affects the integrity of the membrane, but not the conductivity 1A 2C