聚醚砜接枝聚乙二醇共聚物的点击制备

Preparation of polyether sulfone graft copolymer membrane and its gas separation performance

为制备结构可调、侧链带有可反应性双键官能团聚合物,提出了一种用点击化学调控接枝共聚物精细结构的方法,以聚醚砜类聚合物为主链,聚乙二醇为侧链,制得微观结构可调的功能性聚醚砜基接枝共聚物。首先以二烯丙基双酚硫、双酚硫、4,4-二氟二苯砜为反应单体,利用缩聚反应合成了2种不同双键侧基含量的聚醚砜(PES A(14%)、PES B(28%));之后利用巯基-烯点击化学的方法,将巯基PEG作为接枝侧链,制备了聚醚砜接枝共聚物(PES-g-PEG);通过调节聚醚砜双键的含量与聚乙二醇的分子量调节接枝密度与接枝链长,从而调节其精细结构,为接枝共聚物的可控制备提出了新的方法。结果表明:1H-NMR、红外表征证明功能性聚合物的成功制备;热重分析仪(TG)分析结果表明聚合物的起始分解温度高于350℃,其热稳定性良好;凝胶渗透色谱仪(GPC)表征表明,PES A的Mn为67000,相对分子质量分布为2.40,PES B的Mn为52000,相对分子质量分布为2.30;差式扫描量热结果表明,聚合物处于无定形态,出现了2个玻璃化转变温度,出现了微相分离。

In order to prepare polymer with adjustable structure and side chain with reactive double bond functional group,a method for efficiently preparing graft copolymer was proposed.The polyethersulfone-based polymer was used as a substrate to efficiently prepare a functional polyethersulfone-based graft copolymer with adjustable structure.Firstly,the PES of two different contents of double-bond side groups(PES A(14%)and PES B(28%))were synthesized by condensation reaction using diallylbisphenol-sulfur,bisphenol-sulfur,4,4-difluorodiphenylsulfone as reaction monomer.Then,polyether sulfone graft copolymer(PES-g-PEG)was prepared by grafting mercapto polyethylene glycol by thio-ene click reaction.By adjusting the content of double bond of polyethersulfone and the molecular weight of polyethylene glycol,the graft density and graft chain length of synthesized copolymer and its fine structure were adjusted,and a new method was proposed for the control of graft copolymer.The results show that 1H-NMR and FT-IR spectra prove the successful preparation of functional polymers.The TG results show that the initial decomposition temperature of the polymer is above 350℃,and the thermal stability is good;GPC showed that PES A had a Mn of 67000 with a molecular weight distribution of 2.40,and PES B of 52000 with a molecular weight distribution of 2.30.Differential scanning calorimetry results show that the polymer stays in amorphous state,two glass transition temperatures appear,and microphase separation occurs.