INVITRO AND INVIVO INVESTIGATION OF A RANGE OF PHOSPHATE GLASS-REINFORCED POLYHYDROXYBUTYRATE-BASED DEGRADABLE COMPOSITES

A completely degradable melt-processed composite was produced using a phosphate-based glass in the soda-lime-phosphorus pentoxide ternary phase system. In vitro degradation studies showed that the mass loss and mechanical property change could be closely correlated with the solubility rate of the reinforcing glass. The in vivo studies showed a slight inflammatory reaction, but good compatibility. With time, this inflammatory reaction disappeared and the initial reaction was interpreted as being due to a high solubility rate of the glass. The high solubility of the glass was derived not from the composition, but because the glass was in particulate form and therefore had a high surface area. This was of interest, as it showed that the polymer was highly permeable and did not encapsulate the glass as expected with a melt-processing method.