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The fabrication of tissue engineering scaffolds based on the polymerization of crosslinked polylactide using leaching and batch foaming to generate well‐controlled and interconnected biodegradable polymer scaffolds is reported. The scaffold fabrication parameters are studied in relation to the interpore connectivity, pore morphology, and structural stability of the crosslinked PLA scaffold. In vitro cell culture and in vitro degradation are used to analyze the biocompatibility and biodegradability of the scaffolds. The new crosslinked PLA thermoset scaffolds are highly suitable for bone tissue engineering applications due to their complex internal architecture, thermal stability, and biocompatibility. magnified image

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Polycarbonate based thermoplastic polyurethanes (CPU2) were prepared and coated onto polyamide 6 (PA 6) fibers. The CPU2 thin film coatings were prepared by dipping the PA 6 fibers into a viscous CPU2 adduct and cured at 100 C for 12 h. Both the tensile strength and the elongation at break of the CPU2 thin film coated PA 6 fibers (CPU2-PA6) increased although both the magnitudes of CPU2 are much lower than for the original PA 6 fibers. FE-SEM observation revealed that there existed an interface interaction region of 10 mm at the interface of PA 6 fiber and the CPU2 thin film coating. Generally speaking, it is considered that the break of PA 6 fibers is due to the formation of the micro-cracks on the fiber surface when it is under a tensile load. The coating of CPU2 onto the PA 6 fibers reduced the formation of micro-cracks during the elongation process, resulted in the improvement of the mechanical properties. Also, the CPU2-PA6 fibers when exposed to weathering tests to check the weathering resistance, showed an increase in the tensile strength for 0-50 h of exposure. This was due to the UV light induced crystalline transformation, i.e., from the crystalline phase to the crystalline phase. The CPU2-PA6 fibers almost retained the strength even after 200 h of exposure in a weatherometer. The crystalline transformations due to the UV irradiations have not been reported yet. Also, the CPU2 showed good adhesion property with the PA 6 films. The blending with various polymers or composites is generally employed for the performance enhancement of PA 6 fibers. On the contrary, the method employed in this study improved the performance of PA 6 fibers without changing its inherent morphological properties.KEY WORDS: Polyamide 6 Fiber / Polyurethane Thin Film / Coating / Micro-cracks / Interface Interaction / Plastic-type Break / Metallic-type Break / Weathering Tests / Polyamide fibers (PAs) are used for a wide variety of applications. They include the textile industry, engineering applications, biomedical and marine applications. The properties of PAs are the high melting point, good mechanical strength, good resistance to hydrocarbons, and the ease of fabrication and processing.1-3 However, the polyamide 6 (PA 6) fibers are prone to break under the mechanical stress due to the formation of micro-cracks on the surface. While, the polyurethanes are widely used in the coatings, adhesives, sealants, foams, elastomers and so on. Thermoplastic polyurethane elastomers are well known for their abrasion resistance, flexibility and high cohesive strength. [4][5][6] They are synthesized from the polymer glycol, diisocyanate and a chain extender. The final structure of polyurethane consists of a soft segment formed from the polymer glycol and a hard segment from the diisocyanate and the chain extender. The soft segment can be classified as an ether or ester series, including the carbonate ones. 7,8 Studies have been reported with polyamide in the thermoplastic elastomers or rubbers as blends. 9 The PA 6/acrylonitrile-butadiene-sty...