Surface microstructure of MMA‐HEMA polymer membranes

摘要

AbstractA series of MMA‐HEMA polymer (hydroxyethyl methacrylate) membranes were prepared using several copolymer precursor mixtures and were characterized by transmission and scanning electron microscopy. The correlation between the preparation methods and the microstructure of the porous layers was sought. The cryofracture procedures also were investigated in order to observe the polymer membranes in the electron microscope. It was found that the porosity of the intermediate transport layer depends on the molecular weight composition and the MMA/HEMA copolymer ratio; the presence of dimethylformamide (DMF) also has a marked influence on the microtextural properties of the transport layer. The main features of the selective layer surface are the very fine roughness, with pits and pores in the 1‐5 nm range, and the chainlike protuberances at the nanometer scale. The cryogenic fracture methods proved adequate for observation of the new MMA‐HEMA‐type membranes without artifacts. © 1993 John WileyS