The effect of fabrication methods on the mechanical and thermal properties of poly(lactide-co-glycolide) scaffolds

The purpose of this research was to evaluate the effects of the fabrication method, poly(ethylene glycol) (PEG) molecular weight, and PEG concentration on the mechanical and thermal properties of blended poly (lactide-co-glycolide) (PLGA)/PEG scaffolds. The manufacturing process was the dominant factor. The tested fabrication processes were compression, heat molding, and solvent casting/vacuum drying. The scaffolds produced by compression were strong and brittle with mechanical properties [compressive modulus (E) similar to 400 N/mm(2)] comparable to those of trabecular bone. The heat-molded scaffolds were weaker and more ductile (E similar to 45 N/mm(2)) than the compressed scaffolds, so they were more applicable to non-load-bearing applications. The vacuum-dried scaffolds completely lacked compressive strength (E similar to 5 N/mm(2)) and were considered unsuitable for scaffolding applications. The miscibilities of the blends were also affected by the processing method and were evaluated on the basis of the melting-point depression of crystalline PEG. The miscibility of PLGA in PEG was greatest with vacuum drying (6-13%), followed by heat molding (0.4-1.5%) and then compression (0.20.8%). The application of heat and solvent to the blend successfully altered the miscibility of the two polymers. Overall, this study demonstrates the ability to fabricate scaffolds with distinct thermal and mechanical characteristics by the manipulation of the fabrication method. (c) 2007 Wiley Periodicals, Inc.