Supporting Information

Cross-Linked Highly Sulfonated Poly(arylene ether

sulfone) Membranes Prepared by in-situ Casting and

Thiol-ene Click Reaction for Fuel Cell Application

Jusung Hana††, Kihyun Kimb††, Junghwan Kima, Sungjun Kima, So-Won Choic, Hyunhee Leea,

Jin-joo Kima, Tae-Ho Kimc, Yung-Eun Sunga and Jong-Chan Leea,＊

aDepartment of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National

University, 599 Gwanak-ro, Gwanak-gu, Seoul 151-744, Republic of Korea

bSchool of Materials Science and Engineering Polymer Science and Engineering and ERI (Engineering and

Engineering Research Institute), Gyeongsang National University, 501 Jinju-daero, Jinju, 660-701, South

Korea

cCenter for membrane, Korea Research Institute of Chemical Technology, P.O. Box 107, Yuseong, Daejeon 305-

600, Republic of Korea

†† These authors contributed equally to this work

* Corresponding Author: Tel. +82 2 880 7070 / fax: +82 2 880 8899; e-mail: jongchan@snu.ac.kr1

Fig. S1. 1H NMR spectrum of purified 2,2'-diallylbisphenol A (DBPA).

2

Fig. S2. 1H NMR spectra of OH-SPAES, DFBP-SPAES and SH-SPAES.

3

Fig. S3. (a) FT-IR spectra of SH-SPAES, C-SPAES_X, and VPSf. (b) The functional group

ratio between vinyl (-C=C) and thiol (-SH) groups calculated from the number average

molecular weight (Mn) analyzed by GPC.

4

Fig. S4. Gel fraction test of membranes in N,N-dimethylacetamide (DMAc) solvent at 80 oC

for 1 h.

5

Fig. S5. Surface SEM images of the membranes. (a) SPAES(50) (b) C-SPAES_9 (c) SPAES.

Cross-section SEM images of the membranes. (d) SPAES(50) (e) C-SPAES_9 (f) SPAES.

6

Fig. S6. Volume-based dimensional change of SPAES and C-SPAES_15 membranes after 6 h

in deionized water at room temperature.

7

Fig. S7. TGA curves of VPSf, SPAES and C-SPAES_X.

8

Fig. S8. Stress-strain curves of SPAES and C-SPAES_X.

9

Fig. S9. AFM phase images of (a) SPAES(50), (b) C-SPAES_9, (c) SPAES.

10

Fig. S10. EIS analysis for estimation of membrane resistance of C-SPAES_7 and Nafion 212

membranes (80 oC, 100% RH and 0.6 A cm-2 of DC with an amplitude of 5 mV over the

frequency range of 0.1 Hz to 100 kHz)

11

Table S1

Water uptake of SPAES, C-SPAES_X, and SPAES(50) at 80 oC.

a SPAES with degree of sulfonation of 50 mol%.

Table S212

Samples Water uptake (%)

SPAES -

C-SPAES_5 37.3

C-SPAES_7 33.4

C-SPAES_9 29.7

C-SPAES_15 24.1

SPAES(50)a 29.3

A comparison of reported cross-linked membranes and Nafion.

Reference MembraneProton Conductivity

(mS cm-1) at 80 oC

- C-SPAES_7

11.9 (50% RH)

43.0 (70% RH)

190.6 (99% RH)

Macromolecules, 48 (2015) 1104-

1114C-SPAES-40

9.2 (50% RH)

42.3 (70% RH)

Solid State Ionics 303 (2017) 126-

131CSPEN-70 145-150 (100% RH)

European Polymer Journal 103

(2018) 322–334PTCTSH-90/PVA 104 (100% RH)

J. Power Sources 332 (2011)

9946-9954CMB2

7-8

(at 60 oC and 50% RH)

26-28

(at 60 oC and 70% RH)

135-145

(at 60 oC and 100% RH)

J. Membr. Sci., 549 (2018) 567–

574CL-SPAEK/silica

8-9

(at 70 oC and 50% RH)

220-230

(at 70 oC and 99% RH

J. Membr. Sci., 560 (2018) 58–66 Nafion 212

17-19 (50% RH)

41-43 (70% RH)

135-140 (95% RH)

J. Power Sources 332 (2016) 265-

273Recast Nafion

3.6-3.8 (50% RH)

12-14 (65% RH)

120-130 (100% RH)

13