本實驗將PHB與PLA兩種高分子溶於chloroform與DMF的共溶劑系統，固定高分子濃度為7 wt%，探討不同PHB/PLA組成溶液對電紡製程中溶液性質、纖維形態、分子鏈順向度、結晶度等影響。實驗發現：不同組成溶液皆可藉由電紡製備出纖維，當PLA含量愈多，纖維直徑愈細。
利用DMF可將複合纖維中的PLA成分萃取出來，經處理後的纖維直徑下降且表面無孔洞結構，顯示電紡所得複合纖維為一種特殊的PHB/PLA芯鞘型纖維，其中芯部為PHB而鞘層為PLA成分。由FT-IR可分析此芯鞘型纖維之內徑、組成重量分率與晶體順向度。
由纖維膜應力-應變曲線得知，PHB纖維膜的較硬脆，PLA則較軟韌。添加PLA於PHB中可改善纖維膜韌性，當PHB/PLA比例為50/50時纖維膜的韌性最大。

This research is to study the correlation between the solution properties and the fiber morphologies, crystal orientation as well as crystallinity in electrospinning of the 7 wt% PHB/PLA blend solutions. Uniform fibers can be obtained by changing the blend composition. The fiber diameters become thinner as the PLA content is increased.
PLA component of composite fibers can be extracted out by DMF. The fiber diameter decreases and porous structure is not observed, suggesting that the as-spun composite fiber forms the PHB/PLA core/shell fiber. Fourier transform infrared spectroscopy is used to analyze the inner diameter of core/shell fiber, weight fraction of polymer and crystal orientation.
From the stress-strain curves of fiber mats, we conclude that PHB is stiff and brittle, but PLA is soft and ductile. With incorporation of PLA into the PHB fiber, the toughness of fiber mats can be improved. When the blend ratio of PHB/PLA is 50/50, maximum toughness is obtained.

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