Abstract: A nanofiltration (NF)composite membrane, with an ultra-thin skin layer, was prepared through interfacial polymerization on a polysulfone support with trimesoyl chloride (TMC)and a key aqueous monomer trimesoyl piperazine (TMPIP)hydrochloride with branched triimine structure, which was designed and synthesized based on the principle of interfacial polymerization of TMC and piperazine (PIP).Fourier transform infrared spectroscopy (FTIR)was combined with scanning electron microscope (SEM)to characterize the chemical composition and structure of the skin layer. The results showed that an ultra-thin poly(piperazineamide)skin layer, around 100 nm thick, was formed on the surface of support membrane. Compared with the performance of TMC/PIP composite membrane against PEG 200, the improved performance of TMC/TMPIP composite membrane was attributed to its high crosslinking and ultra-thin skin layer. The performance for aqueous solution of different salts was investigated, and it was found that the rejection and flux were both better than those of TMC/PIP composite membrane, with the same rejection order.

Key words: trimesoyl piperazine hydrochloride, trimesoyl chloride, interfacial polymerization, nanofiltration composite membrane, ultra-thin skin layer

摘要： 基于哌嗪(PIP)与均苯三甲酰氯(TMC)界面聚合制备纳滤膜的原理，设计并合成了具有支化结构的三亚胺功能基团水相单体——均苯三甲酰哌嗪(TMPIP)盐酸盐，并与TMC界面聚合制得分子结构与TMC/PIP相同的TMC/TMPIP超薄纳滤复合膜。采用傅里叶红外光谱(FTIR)和扫描电镜(SEM)表征了复合膜皮层的化学结构和表面形貌，结果表明在聚砜底膜表面形成了膜厚为100 nm左右的TMC/TMPIP超薄皮层。通过与TMC/PIP复合膜对PEG 200水溶液的分离性能相比较发现，TMC/TMPIP复合膜因其高度的网络化结构和超薄皮层，因而具有更高的截留率和水通量。考察了TMC/TMPIP复合膜对水中不同盐的截留性能，其截留率顺序与TMC/PIP复合膜相同，而通量和截留率均优于后者。

关键词: 均苯三甲酰哌嗪盐酸盐, 均苯三甲酰氯, 界面聚合, 纳滤复合膜, 超薄皮层