Effects of Substrate on Interfacial Polymerization: Tuning the
Hydrophobicity via Polyelectrolyte Deposition
Abstract
Interfacial polymerization (IP) has been the key method for fabricating
thin film composite (TFC) membranes. However, the role of the substrate
surface hydrophilicity in the IP-film formation remains a controversial
issue to be further addressed. This study characterized the IP films
formed on a series of polyacrylonitrile (PAN) substrates whose
hydrophilicity were varied via different approaches, including the
alkaline treatment and the deposition of various polycations. It was
revealed that delamination could occur when the IP film was formed on a
relatively hydrophilic surface; the integrity of the TFC membranes was
substantially improved owing to the modification of polyelectrolyte
deposition. On the other hand, the characterization indicated that the
TFC membrane could have an enhanced efficiency when the substrate was
relatively hydrophilic. It is established that the polyelectrolyte
deposition can be exploited to effectively tune the substrate surface
hydrophobicity, thereby increasing the degrees of freedom for optimizing
TFC membranes fabrication.