This study presents a comprehensive, side-by-side analysis of chemical, thermal, mechanical, and morphological changes in four polymers used in tissue engineering: poly(glycerol-sebacate) (PGS), poly(lactic acid) (PLA)/poly(e-caprolactone) (PCL) blend, poly(lactic-co-glycolic acid) (PLGA), and Texin 950, a segmented polyurethane resin (PUR). Polymer foams were created using a salt-leaching technique and then analyzed over a 16-week period. Biodegradation was analyzed by examining the morphology, thermal properties, molecular weight, chemical, and mechanical properties using scanning electron microscopy, differential scanning calorimetry, gel permeation chromatography, attenuated total reflectance-Fourier transform infrared spectroscopy, thermogravimetric analysis, and compression testing. PGS underwent the most rapid degradation and was hallmarked by a decrease in compressive modulus. PLA/PCL blend and PLGA both had rapid initial decreases in compressive modulus, coupled with large decreases in molecular weight. Surface cracks were observed in the PUR samples, accompanied by a slight decrease in compressive modulus. However, as expected, the molecular weight did not decrease. These results confirm that PUR does not undergo significant degradation but may not be suitable for long-term implants. The biodegradation rates of porous PGS, PLA/PCL blend, and PLGA found in this study can guide their use in tissue engineering and other biomedical applications.

Gram scale Fe100−xCox alloy nanoparticles with an average particle size of about 30 nm were synthesized in an inert atmosphere using a modified polyol process. The x-ray diffraction pattern clearly shows the formation of Fe100−xCox alloy nanoparticles. Electron microscopy studies depict the cubic morphology for the Fe57Co43 nanoparticles and nearly hexagonal shape for the Co66Fe34 alloy nanoparticles. The magnetic moment of Fe57Co43 nanoparticles that were synthesized in gram scale, were in the range of 21–21.5 kG (±0.5 kG) at room temperature and the Co66Fe34 nanoparticles were in the range 17.5–18 kG (±0.5 kG). Both samples had the intrinsic coercivity in the range of 150–165 Oe. The as-synthesized nanoparticles were used to fabricate the nanocomposite magnet by the hot press method. The composite demonstrated an exchange-coupled effect with a 15% enhancement of magnetic moment and remanence with a 2% addition of Fe57Co43 nanoparticles.

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