Abstract A novel surface modification technique for polyimide membranes, their characterization and organic solvent filtration performance is described. The process involves treating crosslinked polyimide support membranes with surface initiators followed by Single Electron Transfer - Living Radical Polymerization (SET-LRP) with three alkyl methacrylates. Proof of grafting is established using ATR-FTIR, XPS and FESEM. The degree of grafting (DG) and brush height were a function of monomer type and polymerization time and provide a unifying basis for correlating selectivity and permeability. The permeability of these composite membranes, evaluated with 6 organic solvents (alcohols), correlated with solvent properties and can be tailored with DG. Filtration performance was assessed by measuring the selectivity and fouling of the organic dye Rose Bengal (RB) in ethanol. The polarized wall concentration increased with DG, whereas the RB sieving coefficient decreased with DG. Flux decline during RB filtration was best described by pore blocking and by heterogeneous and Langmuir sorption models. These studies provide a basis for designing polymeric membranes comprising branched brush selective layers with defined microstructure not possible with the widely popular phase inversion process.

中文翻译：

---

通过刷膜过滤有机溶剂：渗透性、选择性和污染与 SET-LRP 接枝程度相关

摘要 描述了一种新型的聚酰亚胺膜表面改性技术、其表征和有机溶剂过滤性能。该工艺包括用表面引发剂处理交联聚酰亚胺支撑膜，然后用三甲基丙烯酸烷基酯进行单电子转移-活性自由基聚合 (SET-LRP)。接枝证明是使用 ATR-FTIR、XPS 和 FESEM 建立的。接枝度 (DG) 和刷子高度是单体类型和聚合时间的函数，为关联选择性和渗透性提供了统一基础。这些复合膜的渗透性，用 6 种有机溶剂（酒精）评估，与溶剂特性相关，可以用 DG 定制。通过测量有机染料玫瑰红 (RB) 在乙醇中的选择性和污垢来评估过滤性能。极化壁浓度随着 DG 的增加而增加，而 RB 筛分系数随着 DG 的增加而降低。RB 过滤过程中的通量下降最好通过孔阻塞以及异质和朗缪尔吸附模型来描述。这些研究为设计包含支化刷选择层的聚合物膜提供了基础，该层具有确定的微观结构，而广泛流行的相转化过程是不可能的。