Microstructure and properties of polyhydroxybutyrate-calcium phosphate cement composites

Abstract

AbstractThe biopolymer (polyhydroxybutyrate) microparticles-calcium phosphate composites were prepared by mechanical mixing of the basic composite components with the addition of hardening liquid after ethanol-composite mixture suspension moulding. The composite microstructures were more compact than the pure cement samples as confirmed by the lower values of specific areas and mesopore volumes. Both the specific areas and mesopore volumes decreased with soaking time in a simulated body fluid. The low polyhydroxybutyrate degradation in composites was found after soaking in simulated body fluid, which was terminated after one week. The formation of a dense apatite layer bonded directly to the surface of polyhydroxybutyrate microparticles was observed. The highest diametral tensile strength (13 MPa) and compressive strength (95 MPa) values of up to 50 % higher than in pure cement were measured in samples with 10 % of polyhydroxybutyrate. The addition of polyhydroxybutyrate microparticles had no effect on the setting time.