Self-adhesive plasticized regenerated silk on poly(3-hydroxybutyrate-co-3-hydroxyvalerate) for bio-piezoelectric force sensor and microwave circuit design

This study shows that regenerated silk (RS), a natural biodegradable and biocompatible polymer, can behave as a self-adhesive thermoplastic material with multifunctional properties. In particular, Ca ions-plasticized RS hybrids with gold nanorods have been produced. It has been found that at mild conditions of temperature and pressure, RS hybrids undergo to the loss of the β-sheet content and forms a tough self-adhesive material on poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) substrate. The structure-dependent piezoelectricity of such RS adhesives on PHBV films was investigated and it was demonstrated that this forms a RS/PHBV piezoelectric sensor that can be used for the monitoring of force. The constitutive parameters (i.e., permittivity and loss tangent) of both PHBV and RS/PHBV were measured in view of their use as dielectric substrates in microwave circuit design. Being fully made of biodegradable and biocompatible materials, this self-adhesive material can be used in tissue engineering for different applications.