Synthesis and Properties of Fluorinated Poly(arylene ether sulfone)s with Sulfonated Pentiptycene Pendants as Proton Exchange Membranes†

doi:10.7503/cjcu20130605

Abstract

Abstract:

Two series of poly(aryl ether sulfone)s[SPES-x-PPD(10F) and SPES-x-PPD(4F)] containing sulfonated pentiptycene groups were synthesized through nucleophilic aromatic substitution polycondensation using pentiptycene-6,13-diol, decafluorobiphenyl, 4,4'-(hexafluoroisopropylidene)diphenol, and 3,3',4,4'-tetrafluorodiphenyl sulfone, followed by postsulfonation with chlorosulfonic acid. The structures of polymers were characterized by ¹H NMR spectra. These ionomers generally show high thermal stability. The correspon-ding membranes generally show good mechanical properties, excellent dimensional changes, good oxidative stability and high proton conductivity under high temperature and low humidity. Transmission electron microscopic photos reveal that the microphase separated structures of SPES-x-PPD(10F) and SPES-x-PPD(4F) membranes are improved greatly after fluorine atoms introducing. Meanwhile, the hydrophilic domain enlarged when the contents of fluorine atoms in polymer backbone increased. This is just the main reason of high conductivity for these membranes.

Key words: Sulfonated triptycene group, Low humidity, Proton exchange membrane, Poly(arylene ether sulfone)s, Fluoride sulfonic acid membrane

CLC Number:

O631

TrendMD:

GONG Feixiang, QI Yonghong, XUE Qunxiang. Synthesis and Properties of Fluorinated Poly(arylene ether sulfone)s with Sulfonated Pentiptycene Pendants as Proton Exchange Membranes^†[J]. Chem. J. Chinese Universities, 2014, 35(2): 433.

Figures/Tables 10

Scheme 1 Synthesis of SPES-x-PPD(4F) and SPES-x-PPD(10F) copolymers

Table 1 Physical properties of PES-x-PPD copolymers

Polymer	n(PPD)/ mmol	n(6F-BPA)/ mmol	n(TFDPS) or n(DFBP)/ mmol	10^-4 M_n	PDI	$η in h a$ / (dL·g^-1)	$η in h b$ / (dL·g^-1)
PES-30-PPD(4F)	1.5	3.5	5	6.5	2.1	0.42	0.59
PES-35-PPD(4F)	1.75	3.25	5	6.8	2.2	0.45	0.65
PES-32-PPD(10F)	1.6	3.4	5	7.3	2.5	0.51	0.73
PES-36-PPD(10F)	1.8	3.2	5	7.5	2.3	0.52	0.75

Table 1 Physical properties of PES-x-PPD copolymers

Polymer	n(PPD)/ mmol	n(6F-BPA)/ mmol	n(TFDPS) or n(DFBP)/ mmol	10^-4 M_n	PDI	$η in h a$ / (dL·g^-1)	$η in h b$ / (dL·g^-1)
PES-30-PPD(4F)	1.5	3.5	5	6.5	2.1	0.42	0.59
PES-35-PPD(4F)	1.75	3.25	5	6.8	2.2	0.45	0.65
PES-32-PPD(10F)	1.6	3.4	5	7.3	2.5	0.51	0.73
PES-36-PPD(10F)	1.8	3.2	5	7.5	2.3	0.52	0.75

Fig.1 1H NMR spectra of PES-32-PPD(10F)(A) and SPES-32-PPD(10F)(B) in DMSO-d6

Table 2 IEC and mechanical properties of SPES-x-PPD(10F) and SPES-x-PPD(4F) membranes

Polymer	IEC/(mmol·g^-1)			σ_max/MPa(r.t., 60%RH)	ε(%)	E/GPa
Polymer	Calcd.			σ_max/MPa(r.t., 60%RH)	¹H NMR	Titration
SPES-30-PPD(4F)	1.66	1.65	1.66	46.2	7.8	1.145
SPES-35-PPD(4F)	1.88	1.85	1.87	42.5	14	0.916
SPES-32-PPD(10F)	1.65	1.65	1.65	44.7	13	0.989
SPES-36-PPD(10F)	1.82	1.79	1.81	37.7	28	0.710

Fig.2 TGA curves of SPES-35-PPD(4F)(a), SPES-30-PPD(4F)(b), SPES-36-PPD(10F)(c) and SPES-32-PPD(10F)(d) copolymers

Table 3 Water uptake(WU) and swelling ratio of SPES-x-PPD(10F) and SPES-x-PPD(4F) copolymers

Polymer	IEC/(mmol·g^-1)	WU(%)(80 ℃)		Swelling ratio(%)
Polymer	IEC/(mmol·g^-1)	34%RH	94%RH	Δl(20 ℃)	Δt(80 ℃)
SPES-30-PPD(4F)	1.66	7.9	17.6	3.5	7.3
SPES-35-PPD(4F)	1.88	9.8	29.9	6.3	11.6
SPES-32-PPD(10F)	1.65	6.7	13.9	3.1	6.5
SPES-36-PPD(10F)	1.82	8.5	25.2	5.6	10.4
SPES-25-PPD^[27]	1.67	9.3	31.8	11.8	15.6
SPES-30-PPD^[27]	1.92	10.9	39.3	13.7	18.8
Nafion 117	0.91	6.6	11.6

Table 4 Water uptake(WU) and conductivity of SPES-x-PPD(10F), SPES-x-PPD(4F) and Nafion 117 membranes

Polymer	IEC/(mmol·g^-1)	WU(%)(80 ℃)		σ/(S·cm^-1)(80 ℃)
Polymer	IEC/(mmol·g^-1)	34%RH	94%RH	34%RH	94%RH
SPES-30-PPD(4F)	1.66	7.9	17.6	8.56×10⁴	0.173
SPES-35-PPD(4F)	1.88	9.8	29.9	1.46×10³	0.191
SPES-32-PPD(10F)	1.65	6.7	13.9	1.21×10³	0.181
SPES-36-PPD(10F)	1.82	8.5	25.2	2.25×10³	0.213
Nafion 117		6.6	11.6	3.0×10³	0.110

Fig.3 Humidity dependence of the proton conductivity of Nafion 117(a), SPES-36-PPD(10F)(b), SPES-35-PPD(4F)(c), SPES-32-PPD(10F)(d), and SPES-30-PPD(4F)(e) membranes at 80 ℃

Fig.4 TEM images of SPES-30-PPD(4F)(IEC=1.66 mmol/g)(A), SPES-32-PPD(10F)(IEC=1.65 mmol/g)(B), SPES-35-PPD(4F)(IEC=1.88 mmol/g)(C) and SPES-36-PPD(10F)(IEC=1.82 mmol/g)(D)

Table 5 Oxidative stability results of SPES-x-PPD(10F) and SPES-x-PPD(4F) membranes

Polymer	IEC/(mmol·g^-1)	Oxidative stability^a
Polymer	IEC/(mmol·g^-1)	Decrease in mass(%)	Decrease in η_inh(%)
SPES-30-PPD(4F)	1.66	0^a; 7^b	2
SPES-35-PPD(4F)	1.88	2^a; 18^b	7
SPES-32-PPD(10F)	1.65	0^a; 0^b	1
SPES-36-PPD(10F)	1.82	1^a; 10^c	5
Nafion 117	0.91	0^a; 0^b

References 29

[1]	Kreuer K., Chem. Mater., 1996, 8(3), 610—641
[2]	Mauritz A., Moore R. B., Chem. Rev., 2004, 104, 4535—4585
[3]	Yossef A. E., Hickner M. A., Macromolecules, 2011, 44, 1—11
[4]	Hickner M., Ghassemi H., Kim Y., Einsla B., McGrath J., Chem. Rev., 2004, 104(10), 4587—4612
[5]	Eisenberg A., Yeager H.L., Perfluorinated Ionomer Membranes, ACS Symp. Ser., Washington D. C., 1982, 180
[6]	Zhang H. W., Shen P. K., Chem. Soc. Rev., 2012, 41, 2382—2394
[7]	Parka C. H., Lee C. H., Guiver M. D., Lee Y. M., Prog. Polym. Sci., 2011, 36, 1443—1498
[8]	Mohanty A. K., Mistri E. A., Banerjee S., Komber H., Voit B., Ind. Eng. Chem. Res., 2013, 52(8), 2772—2783
[9]	Weiber E. A., Takamuku S., Jannasch P., Macromolecules, 2013, 46(9), 3476—3485
[10]	Miyake J., Watanabe M., Miyatake K., ACS Appl. Mater. Interfaces, 2013, 5(13), 5903—5907
[11]	Lafitte B., Jannasch P., Adv. Funct. Mater., 2007, 17, 2823—2834
[12]	Nanwen L., Dong W. S., Doo S. H., Young M. L., Guiver M. D., Macromolecules, 2010, 43, 9810—9820
[13]	Zhao C., Li X., Wang Z., Dou Z., Zhong S., Hui N., J. Membr. Sci., 2006, 280, 643—650
[14]	Xu D., Wang Y., Zhang Y., Zhang G., Shao K., Li S., Na H., Chem. Res. Chinese Universities, 2010, 26(6), 1031—1034
[15]	Wang Y. P., Yue X. G., Pang J. H., Li X. F., Li Y. N., Zhang H. B., Jiang Z. H., Chem. J. Chinese Universities, 2012, 33(5), 1100—1105
	(王永鹏, 岳喜贵, 庞金辉, 李雪峰, 李摇娜, 张海博, 姜振华.高等学校化学学报,2012, 33(5), 1100—1105)
[16]	Li X. F., Guo M. M., Liu B. J., Jiang Z. H., Chem. J. Chinese Universities, 2011, 32(5), 1022—1024
	(李雪峰, 郭梅梅, 刘佰军, 姜振华.高等学校化学学报,2011, 32(5), 1022—1024)
[17]	Pang J. H., Zhang H. B., Li X. F., Jiang Z. H., Macromolecules, 2007, 40, 9435—9442
[18]	Gao N., Zhang S., J. Appl. Polym. Sci., 2013, 128, 1—12
[19]	Peckham T., Holdcroft S., Adv. Mater., 2010, 22, 4667—4690
[20]	Miyatake K., Chikashige Y., Higuchi E., Watanabe M., J. Am. Chem. Soc., 2007, 129(13), 3879—3887
[21]	Matsumoto K., Nakagawa T., Higashihara T., Ueda M., J. Polym. Sci. Part. A: Polym. Chem., 2009, 47, 5827—5834
[22]	Nakabayashi K., Higashihara T., Ueda M., J. Polym. Sci. Part. A: Polym. Chem., 2010, 48, 2757—2764
[23]	Matsumoto K., Higashihara T., Ueda M., Macromolecules, 2009, 42(4), 1161—1166
[24]	Matsumura S., Hlil A., Lepiller C., Gaudet J., Guay D., Shi Z., Holdcroft S., Hay A., Macromolecules, 2008, 41(2), 281—284
[25]	Miyatake K., Shimura T., Mikami T., Watanabe M., Chem. Commun., 2009, 42, 6403—6405
[26]	Gong F., Mao H., Zhang Y., Zhang S., Xing W., Polymer, 2011, 52, 1738—1747
[27]	Gong F., Zhang S., J. Power Sources, 2011, 196, 9876—9883
[28]	Wang J. H., Zhao Z., Gong F. X., Li S. H., Zhang S. B., Macromolecules, 2009, 42, 8711—8717
[29]	Rubatat L., Shi Z. Q., Diat O., Holdcroft S., Frisken B. J., Macromolecules, 2006, 39, 720—730