Preparation and Application of Aromatic Polymer Proton Exchange Membrane with Low-Sulfonation Degree

Table 1

Effect of reaction conditions on the degree of sulfonation.

SPPEK quality (g)	Sulfuric acid (ml)	Time (h)	Oleum (ml)	Temperature (°C)	IEC (mmol/g)	DS (%)
6	55	24	0	RT	≈0	≈0
6	55	48	0	RT	0.75	7
6	55	4	0	60	0.71	12
6	30	4	30	RT	0.63	20
6	0	4	30	60	1.06	36
6	0	8	30	60	1.08	48
6	0	24	30	60	1.12	56
6	0	6	30	60	1.14	67
12	0	6	50	60	1.15	85
12	0	7	50	60	1.15	91