PAMAM dendrimer-induced cross-linking modification of polyimide membranes

Abstract

A novel cross-linking agent, PAMAM dendrimer, was employed to chemically cross-link 6FDA-durene polyimide at room temperature. The gel content increased with the immersion time, indicating that there is no reaction between the polyimide chain's mobility and free volume during the modification process. XPS showed that the content of N on the polymer surface increases and its chemical environment changes with increasing modification time. Cross-linking formed through the reaction between the amine groups of dendrimers and imide groups of polyimide, monitored by FTIR-ATR. The CO2 permeability increase after modification was attributed to a significant increase of solubility in the cross-linked polymer.