Composite coatings based on linear and branched block copolymers for hydroxyapatite deposition in simulated body-fluid

Abstract

In this work, the fabrication of composite coatings based on block copolymers and silicates deposited on stainless-steel plates through electrophoretic deposition technique was studied. Linear poly(ɛ-caprolactone), and poly(dimethylsiloxane-block-ε-caprolactone) copolymers were obtained through ROP polymerization, whereas branched poly(hydroxyethyl methacrylate-co-(hydroxyethylmethacrylate-graft-ε-caprolactone)-block-ε-caprolactone) copolymers were synthesized by a one-pot technique by combining ROP and RAFT synthesis. SEM micrographs revealed homogenous and dense structures over the metallic substrate and the absence of micro-cracks. Thermal characterization revealed residual percentages of solids between 63% and 72% wt/wt. Finally, an in-vitro assessment confirmed the presence of a hydroxyapatite layer over coatings after immersion in a simulated body-fluid solution by XRD analyses.