Enhanced compressive strengths and induced cell growth of 1-3-type BaTiO3/PMMA bio-piezoelectric composites

Barium titanate (BaTiO 3 ) has been used as a bone implant material because of its piezoelectric properties and the ability to promote cell growth when combined with hydroxyapatite. However, the brittleness of BaTiO 3 inhibits its use as a bone replacement material at load-bearing sites, and the reduction of BaTiO 3 content in the composite reduces its piezoelectric effect on bone growth. In this study, we explored a preparation method, which included directional freeze casting and self-solidification of bone cement, to obtain 1-3-type BaTiO 3 /PMMA bio-piezoelectric composites with a lamellar structure. The lamellar BaTiO 3 layer through the composite from the bottom to the top significantly improved the piezoelectric properties of the composite. In addition, the dendritic ceramic bridges on the BaTiO 3 pore walls can improve the compressive strength and elastic modulus of BaTiO 3 /PMMA bio-piezoelectric composites with a lamellar structure. More importantly, it was found that polarized lamellar BaTiO 3 could induce osteoblasts to grow in the direction of the BaTiO 3 layers. When the width of the BaTiO 3 layer was in the range of 8–21 μm, osteoblasts along the BaTiO 3 layer showed well growth, which can be of great value for the production of biomimetic bone units.