Development and Characterization of Photoinduced Acrylamide-Grafted Polylactide Films for Biomedical Applications

Abstract

Surface grafting of biodegradable/biocompatible polylactide (PLA) films by a UV-assisted reaction has been developed by employing a hydrophilic acrylamide (Am) monomer, an N,N′-methylenebisacrylamide (MBAm) cross-linker, and a camphorquinone (CQ)/N,N′-dimethylaminoethylmethacrylate (DMAEMA) photoinitiator/coinitiator system. The accomplishment of the process is confirmed by FTIR and XPS analyses. Physicochemical changes of the grafted PLA films are evaluated in terms of chemical structures, radiation-induced degradation followed by crystallization, morphology, thermal properties, and mechanical behavior. The results reveal that a low degree of PLA degradation through chain scission is observed in both blank and grafted PLA films. This generates more polar chain ends that can further induce crystallization. Results from contact angle measurements indicate that the grafted films have higher hydrophilicity and pH-responsive behavior. The incorporation of PAm on the film's surface and the induced crystallization lead to improvements in certain aspects of mechanical properties of the films. The materials have high potential for use in biomedical and environmental applications, such as cell culture substrates or scaffolds or pH-sensitive absorbents.