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چکیده
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PLA is a biocompatible, biodegradable polymer with high mechanical strength. PLA is brittle and its extensibility mostly limited to small deformations and it is brittle, which limits its direct use in biomedical applications. The PCL biopolymer has inadequate strength and modulus for some biomedical applications. Hence, herein PLA/PCL hybrid nanofibers with various ratios were prepared to achieve a biomaterial with optimized mechanical properties. Electrospun fibers of PLA/PCL were fabricated by dual nozzle electrospinning set-up. For this purpose, PLA and PCL were electrospun from opposite nozzles with ratios of 100:0, 70:30, 50:50, 30: 70 and 0:100. The morphology of samples was characterized using scanning electron microscope (SEM). Thermal and mechanical properties were evaluated using a tensile testing machine (Santam S-20) and a dynamic mechanical analyzer (DMA). SEM observations revealed that hybrid nanofibrous mats possessing random orientation morphology without beads were successfully achieved. Tensile test results revealed that the strength and Young’s modulus were remarkably enhanced with increasing PLA content in mats. Contrarily, increasing PCL content in the mats improved extensibility of samples. DMA results showed that the storage modulus E' of samples over the whole temperature region is increased with the increasing of PLA content. Dual-electrospinning is used to simultaneously electrospun PLA and PCL, achieving an interwoven polymeric composite of the immiscible polymers with optimized mechanical properties for biomedical applications
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