Electrostatic and hydrophobic controlled self-assembly of PDMS-E grafted gelatin for self-cleaning application.

Understanding the assembly mechanisms of supramolecular architectures in nature is essential for the design and synthesis of novel biomaterials. In the work, self-assembly of gelatin-mono epoxy terminated polydimethylsiloxane polymer (PGG) controlled by electrostatic and hydrophobic interactions between gelatin and sodium dodecyl sulfate (SDS) was investigated in suit. Confocal laser scanning microscopy, circular dichroism spectroscopy, high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy were conducted to reveal the structure evolution of PGG at a molecular level with the increment of SDS concentration, including micro-sized sphere, core-shell and multi-layer structure. Notably, the multi-layer structure was formed from the large contribution of antiparallel β-sheets on the boundary and new hydrophobic aggregation driven by higher monomer conversions. The delicate supramolecular architectures preliminarily present excellent anti-water, anti-contamination and anti-radiation properties in the surface of skin. The excellent self-cleaning function of PGG indicates potential application in biomaterials.