Influence of Surfactants on the Microstructure and Performance of PDMS-E Grafted Gelatin Films

Abstract

Polydimethylsiloxane grafted gelatin (PGG) polymers were prepared from mono-epoxy terminated polydimethylsiloxane (PDMS-E) macromonomer and gelatin, and surfactants were used to enhance the compatibility of the two polymers phases. The influences of surfactants, including sodium dodecyl sulfate (SDS), sodium dodecyl benzene sulfonate (SDBS), dodecyl trimethylammonium bromide (DTBA), and Tritox-100, on the microstructure and performance of polymers films were researched. XPS and FTIR results confirmed that PDMS-E was successfully grafted to gelatin chains. The results of SEM, DSC, TGA and surface contact angle indicated that microstructure of the PGG/SDS film was mainly controlled by the grafting effect on the gelatin matrix, and a tightly cross-linked network structure formed in PGG/SDBS film. However, few changes were present in the DTAB and Tri-100 systems. Surfactants played a crucial role in deciding the detailed microstructure of the grafted gelatin films, and induced the changes of hydrophobicity, flexibility and thermal properties of the polymer films.