Biocompatible and antimicrobial elastomers with controlled hydrophilicity and degradation rate, as well as appropriate stiffness and elasticity, are interesting for biomedical applications, such as regenerative medicine and tissue engineering.

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Acquiring a polymeric nanocomposite with biocompatibility, desirable dynamic‐mechanical‐thermal properties, and piezoelectricity, as well as high loading capacity, is challenging for design polymeric systems with potential applications in tissue engineering and biosensing. In this work, polyvinylidene fluoride (PVDF), poly(ε‐caprolactone) (PCL), and KIT‐6 mesoporous silica particles were used to prepare PVDF/PCL blends and their nanocomposites as potential candidates to meet the characteristics mentioned above. Hence, we deeply investigated the effect of the addition of PCL and KIT‐6 on the compatibility, crystallinity, and engineering properties of immiscible PVDF/PCL blends. PVDF/PCL blends without KIT‐6 particles and 75/25 PVDF/PCL blend containing various amounts of KIT‐6 particles were prepared by solution casting/annealing technique. It was found that PCL decreased the crystallization temperature and melting points of the PVDF component in the blends. The crystallinity and β‐phase content of PVDF reached maximum values for 75/25 PVDF/PCL blend; interestingly, KIT‐6 prevented PVDF crystallization and decreased β‐phase content. The results of thermogravimetric analysis and dynamic‐mechanical thermal analysis revealed that the presence of PCL reduced the thermal stability of the blends. On the other hand, KIT‐6 increased the thermal decomposition temperature and storage modulus of the polymeric matrix.

A series of novel bio-polyester nanocomposites based on glycerin and azelaic acid as monomers incorporating hydroxyapatite (HA) nanoparticles were fabricated via in situ polymerization method. Chemical structure of the samples was investigated by 1 H-NMR, 13 C-NMR, and Fourier-transform infrared spectroscopy (FTIR). Energy dispersive X-ray-mapping analysis illustrated that the nanoparticles were well dispersed in the poly (glycerol azelaic acid) (PGAZ) matrix. Viscoelastic properties of the samples under various frequencies were examined in which the PGAZ specimen containing 1.0 wt% of HA nanoparticles (PGAZH1.0) exhibited superlative properties. Furthermore, the alterations in the glass transition temperature of the samples were comprehensively discussed. Thermal gravimetric analysis displayed that nanocomposites generally have a difference in degradation patterns from that of the pristine sample. Dynamic contact angle demonstrated that the presence of HA nanoparticles imposed a significant influence on hydrophilicity. The hydrolytic degradation values at pH = 7 and pH = 11 were measured and determined that the degradation rate for the PGAZ sample containing 1.5 wt% HA (PGAZH1.5) was higher than those of the other samples. Moreover, in vitro studies elucidated that cell attachment on PGAZH1.0 and PAZH1.5 surfaces were acceptable.

Biocompatible and electrically conductive porous scaffolds with a desirable hydrophilicity and degradation rate and suitable mechanical performance are highly favorable for tissue engineering and regenerative medicine applications. In this study, we fabricated three-dimensional (3D) porous bioscaffolds from poly(ε-caprolactone) and polylactic acid containing different concentrations of zirconia nanoparticles (n-ZrO 2 ) through freeze-drying technique. Afterward, the surface of the scaffolds was coated with an electrically conductive layer through in situ polymerization of polypyrrole (PPy) on the samples. Bioscaffolds exhibited a favorable range of mechanical properties and electrical conductivity, meeting the required mechanical performances and conductivity for a broad range of tissue engineering applications. Coating PPy on the scaffolds resulted in significantly higher hydrophilicity and faster biodegradation rate, as well as a noticeable enhancement on the in vitro cell attachment, proliferation, and viability. Our findings indicated that the simultaneous presence of n-ZrO 2 and PPy in the system presents a noticeable synergistic effect in overall properties and introduces the fabricated 3D porous scaffolds as promising candidates for tissue engineering and regenerative medicine applications.