Thermal behaviour of zircon/zirconia-added chemically durable borosilicate porous glass

Macroporous alkali resistant glass has been developed by making additions of zirconia (ZrO2) and zircon (ZrSiO4) to the sodium borosilicate glass system SiO2–B2O3 Na2O. The glass was made using a traditional high temperature fusion process. Differential thermal analysis (DTA) was carried out to identify the glass transition temperature (Tg) and crystallisation temperature (Tx). Based on these findings, controlled heat-treatments were implemented to separate the glass into two-phases; a silica-rich phase, and an alkali-rich borate phase. X-ray diffraction (XRD) was used to identify any crystal phases present in the asquenched and heat-treated glasses. Fourier transform infrared (FTIR) spectroscopy also proved effective in investigating phase separation and crystallisation behaviour. After leaching, a silica-rich skeleton with an interconnected pore structure and a uniform pore distribution was observed. Pore characterisation was carried out using mercury porosimetry. The size and shape of the pores largely depended on the heattreatment temperature and time. ZrO2/ZrSiO4 additions increased the alkali resistance of the porous glass 3–4 times

Combinational processing of 3D printing and electrospinning of hierarchical poly(lactic acid)/gelatin-forsterite scaffolds as a biocomposite: Mechanical and biological assessment

In this research, hierarchical scaffolds including poly(lactic acid) (PLA) micro struts and nanocomposite gelatin-forsterite fibrous layers were developed using fused deposition modeling (FDM) and electrospinning (ES), respectively. Briefly, geometrically various groups of pure PLA scaffolds (interconnected pores of 230 to 390 μm) were fabricated using FDM technique. After mechanical evaluation, ES technique was utilized to develop gelatin-forsterite nanofibrous layer. To study these scaffolds, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, and uniaxial compression tests were performed. Furthermore, bioactivity of the scaffolds was evaluated by immersing in the simulated body fluid and apatite formation on the surface of the scaffolds was investigated. Results depicted that elastic modulus of PLA/gelatin-forsterite scaffolds, fabricated by a combinational approach, was significantly higher than that of pure one (about 52%). SEM images showed the formation of calcium phosphate-like precipitates on the surface of these scaffolds, confirming the effects of nanocomposite fibrous layer on the improved bioactivity of the scaffolds. Regarding the obtained biological as well as mechanical properties, the developed bio-composite scaffolds can be used as a biocompatible candidate for bone tissue regeneration