| Summary: | 碩士 === 國立成功大學 === 生物醫學工程學系 === 103 === It is challenging to fabricate electrospun PGS nanofibers because of the poor electrospinnability of its prepolymer and fully crosslinked polymer the low molecular weight. In this study, coaxial electrospinning, which allows a non-electrospinnable polymer to be drawn by a electrospinnable polymer was used aiming at fabricate PGS nanofibers. PLA was used as shell material because it does not melt at PGS curing temperature confining PGS prepolymer in the core. Specifically, the effects of adding PEO in the shell solution were investigated; PEO was removed prior to curing. The fibrous membranes were cured in a vacuum oven at varying temperatures for different reaction time. Transmission electron microscopy was used to illustrate core-shell structure of the fibers. Scanning electron microscopy was used to examine the morphology of membranes. Fourier transform infrared spectroscopy was used to confirm functional group of the membrane after removing PEO and PLA shell. Mechanical properties of the membrane were examined by uniaxial tensile testing. The addition of PEO decreased the fiber diameter. Consistent with previous studies, we found that both the higher curing temperature and the longer duration of curing increased the stiffness of the membrane. We found that PLA appeared to play a role in the mechanical properties of electrospun PGS membrane. The electrospun core/shell PGS/PLA membranes fabricated with PEO/PLA mixture as shell material are more compliant. Moreover, increasing the PGS concentration in the core, the electrospun membrane became stiffer. The core seemed to dominate the mechanical properties of the membrane when 70% PGS was used as the core solution. Finally, electrospun PGS membrane with no PLA in the shell were achieved from the fibers fabricated with 70% PGS as the core solution and PEO/PLA mixture as the shell material. After the removal of PLA shell, PGS fibrous membrane was more compliant and had better flexibility. The Young’s modulus of electrospun PGS membrane was in the range of 0.47~1.03MPa, depending on curing conditions, which is similar to that of soft tissues. We also demonstrated by seeding smooth muscle cells on the membranes containing aligned fibers and found that they have potential of guiding cells alignment.
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