Herein, a technique for the preparation of a new poly(lactide-co-glycolide) (PLGA)/poly(trimethylene carbonate) (PTMC) composite porous polymeric structure involving blending polymers with salt particles via freeze-drying/particulate leaching was developed. This developed technique combined the advantages of both the solution freeze-drying and particulate leaching techniques. The polymer–salt composite was processed using the corresponding method in devices with various shapes and sizes, which could subsequently be extracted to yield the desired porous structures. The effects of different preparation conditions on the properties of the microstructures, connectivity, porosity and compressible strength of the composites were investigated. Depending on the preparatory conditions, including the salt proportion and solution concentration, the resulting porosity of the porous structure was in the range of 80–98%, and the compression strength of the composite varied in the range of 0.56 MPa to 7.98 MPa. Moreover, the cell proliferation results confirmed that the porous polymeric scaffold exhibited good biocompatibility. Consequently, the results indicated that 85 wt% NaCl and 20 w/v% solution concentration were the optimum conditions to achieve the best mechanical enhancement effect and in vitro bioactivity, suggesting that this composite has great potential to be used as a bone repair material in the future.

Ureteral stents have been widely used as biomedical devices to treat some urological diseases for several decades. However, the encrustation complications hamper the long-time clinical use of the ureteral stents. In this work, a new type of biodegradable material for the ureteral stents, methoxypoly(ethylene glycol)-block-poly(L-lactide-ran-Ɛ-caprolactone) (mPEG-PLACL), is evaluated to overcome this problem. The results show that the hydrophilicity and degradation rate in artificial urine of mPEG-PLACL are both significantly increased. It is worth noting that the mPEG-PLACL shows a lower amount of encrustation after immersing the stents in the dynamic urinary extracorporeal circulation (DUEC) model for 7 days. In addition, 71% Ca and 92% Mg are inhibited in vivo by quantitative analysis. Pathological analysis exhibit that the mPEG-PLACL cause less diffuse mucosal hyperplasia after 7 weeks of implantation. All the results indicate that this new type of biodegradable material had an excellent potential for the ureteral stents in the future.

The in-vitro degradation behavior of poly(glycolic acid) (PGA) rods and the composite rods containing poly(L-lactic acid) (PLLA) were investigated via mass loss, pH value change, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Since the degradation rate of PLLA is lower than that of PGA, PLLA/PGA composite rods exhibit a slower degradation rate in comparison with PGA. This finding indicated that it was possible to control the degradation rate of the composites by changing their composition. This result indicates that this kind of composite biomaterial may be applicable to devices for the need of prolonged degradation.