磺化聚醚砜的制备及性能

Preparation of Sulfonated Polyethersulfone

以浓硫酸为溶剂,发烟硫酸为磺化剂,对聚醚砜(PES)进行了磺化改性,并对磺化时间、反应温度、干燥方式和发烟硫酸与PES摩尔比等因素进行了探讨,结果表明,磺化时间为5h时,反应接近平衡点,磺化温度为10℃左右,产物磺化度较高,PES经室温真空干燥比经烘箱干燥获得反应产物磺化度更高,当以SO3计的发烟硫酸与PES的摩尔比为0～2.46时,磺化度和发烟硫酸与PES的摩尔比几乎呈线性关系。采用磺化时间为5h,反应温度10℃,真空15℃干燥24h,n(SO3)/n(PES)=2.46时,可得到磺化度为37.76%的磺化聚醚砜,重均分子量仅下降一半左右,玻璃化温度不变,但较聚醚砜出现了一定的晶态结构。

In this paper polyethersulfone（PES） was dissolved in concentrated sulfuric acid and modified by oleum as sulfonated agent. The influence of sulfonation time,reacting temperature,the mole ratio of oleum to PES,and the drying manner of PES on the sulfonation degrees was studied. The results show that after 5 hours,the sulfonation reaction approaches equilibrium point. High sulfonation degree is gotten when the reacting temperature is in 10 ℃. The room temperature vacuum drying manner of PES leads to higher sulfonation degree rather than high temperature oven drying. The sulfonation degree of SPES increases linearly with the mole ratio of oleum（SO3）/PES during the range of 0～2.46. The SPES product with sulfonation degree of 37.76% is gotten when PES is vacuum dried at 15 ℃ for 24 h,the mole ratio of oleum/PES is 2.46,and the reacting temperature is 10 ℃ for 5 h. The weight-average molecular weight decreases to about half of the source PES. The glass transition remained unchanges. But a certain crystalline state appeares in product SPES caused by its polar sulphoacid group.