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Radiation effects of low-density polyethylene/ethylene-vinyl acetate copolymer (LDPE/EVA) blends were discussed. EVA content in the LDPE/EVA blends was an enhancement effect on radiation crosslinking of LDPE/ EVA blends, and the highest radiation crosslinking was obtained when the EVA content was reached at 30% when irradiated by ␥-ray in air. The phenomenon was discussed with the compatibility, morphology, and thermal properties of LDPE/EVA blends and found that the enhanced radiation crosslinking of the LDPE/EVA blends was proportional to the good compatibility, the increasing degree of the amorphous region's content of the LDPE/EVA blends, and the vinyl acetate content of EVA. We also found that the vinyl acetate of EVA in the blends is easily oxidized by ␥-ray irradiation in air. The possible radiation crosslinking and degradation mechanism of LDPE/EVA blends was discussed quantitatively with a novel method "step-analysis" process of irradiated LDPE/EVA blends in the thermal gravimetric analysis (TGA) technique

Novel porous polycaprolactone/chitosan blend scaffolds were fabricated via a particle-leaching technique using hexafluoro-2-propanol as a shared solvent and salt particles as porogen. By selecting optimized processing conditions, numerous blend scaffolds were already built with well-controlled porous structures and approximately similar pore parameters. The interactions between these scaffolds and the rat osteoblasts were further investigated by measuring the adhesion, proliferation, and morphologies of cells as well as the corresponding alkaline phosphatase activity during various culture periods in vitro. Data collected from different measurements reflected that by incorporating an appropriate amount of chitosan component, the resultant blend scaffolds could improve the adhesion and growth of osteoblasts and exert a significant impact on the osteoblastic phenotype.

Polycaprolactone (PCL) and chitosan were blended to fabricate porous scaffolds for tissue-engineering applications by employing a concentrated acetic acid solution as solvent and salt particles as porogen. These scaffolds showed well-controlled and interconnected porous structures. The pore size and porosity of the scaffolds could be effectively modulated by selecting appropriate amounts and sizes of porogen. The results obtained from compressive mechanical measurements indicated that PCL/chitosan could basically retain their strength in their dry state compared to individual components. In a hydrated state, their compressive stress and modulus could be still well maintained even though the weight ratio of chitosan reached around 50 wt%.