Quartz Crystal Microbalance (QCM) has been typically used as a mass sensor in the study of monolayer and multilayer depositions and dissolution, mass transport in polymer films on electrodes, corrosion processes at electrodes and mass changes caused by protein adsorption at electrodes. Thin films of an aromatic poly (amide ester) hydrogel with hydrolyzable cross links were prepared in-situ on a gold-coated quartz crystal which is the transducing element of a Quartz Crystal Microbalance (QCM). Here we report the synthesis and degradation behavior of an aromatic poly (amide ester) hydrogel with hydrolyzable cross links using QCM. Degradation of the hydrogel films was found to proceed with Δf increment, indicating mass decrease and is in line with the theory proposed by Sauerbrey. Films with a higher cross-link density underwent partial degradation with swelling; and are depicted as a decrease in the Δf values with time. Deviation from the general base catalysis of ester hydrolysis was observed at higher base concentration due to the biphasic environment of the hydrolysis reaction.
A practical guide to quartz crystal microbalance with dissipation monitoring of thin polymer films
