Poly-(lactic acid) infiltration of 45S5 Bioglass® robocast scaffolds: Chemical interaction and its deleterious effect in mechanical enhancement

Strengthening and toughening of robocast 45S5 Bioglass®-derived scaffolds sintered at different temperatures (550-1000 °C) is attempted by PLA infiltration following two different approaches: immersion of sintered scaffolds in molten PLA, to obtain fully-impregnated structures, or in a solution of PLA to produce polymeric coatings. PLA-coated scaffolds showed significantly higher strength and toughness than bare scaffolds both in compression and, especially, in bending. However, molten PLA degraded chemically in the presence of the alkaline ions in 45S5 Bioglass®, an interaction never before reported in the literature, which resulted in color change and cracking of PLA, and which prevented fully-impregnated structures from exhibiting a significant mechanical enhancement over simply coated structures.