Layer-by-layer (LbL) thin films were prepared using carboxyl-terminated poly (amidoamine) dendrimers (generation, 3.5) (PAMAM-COOH) and poly (acrylic acid) (PAA). The stability of the LbL films in aqueous media was evaluated as a function of pH of the media. The PAMAM-COOH-PAA films were stable at pH 2.0-4.5, while the films were decomposed in the solutions of pH 1.5 and pH 5.0-7.0. The pH-stability of the PAMAM-COOH-PAA films was discussed on the basis of the dissociation equilibrium of carboxylic acid residues in PAA and was compared with pH-stability of poly (methacrylic acid) (PMA)-based LbL films. The stability of the PAMAM-COOH-PAA films was different from that of PAMAM-COOH-PMA film. The difference was rationalized based on the acidity of PAA being stronger than that of PMA.
ASJC Scopus subject areas
- Chemical Engineering (miscellaneous)
- Materials Science (miscellaneous)
- Environmental Science(all)
- Polymers and Plastics