本研究使用高溫熔融聚合法合成出一系列的脂肪族聚草酸碳酸共聚酯(Aliphatic oxalic based polycarbonate, AOPC)與脂肪族聚乳酸碳酸共聚酯(Aliphatic lactic based polycarbonate, ALPC)，再以溶液聚合法合成聚草酸碳酸酯聚氨酯(AOPC-PU)與聚乳酸碳酸酯聚氨酯(ALPC-PU)。經DSC 及TGA 分析結果顯示，ALPC-PU 結構中的聚
乳酸碳酸二丁酯與聚乳酸碳酸二己酯為結晶型軟鏈結，當聚乳酸在共聚酯結構中的比例提高，其結晶性與熱穩定降低；AOPC-PU 結構中的聚草酸酯在共聚酯中的比例提高時，同樣會使軟鏈結的結晶性與熱裂解溫度降低。經拉伸測試結果顯示，AOPC-PU 的草酸酯在軟鏈結中的含量增加，會使其剛性下降，延展性提升；另外，提高硬鏈結比例的聚氨酯，剛性高但延展性差。以DMA 分析結果也顯示隨著草酸酯在軟鏈中含量增加會使貯存模數(Storage modulus)下降，而提高硬鏈結比例之聚氨
酯的機械性質較耐高溫。由吸水性試驗可發現草酸酯在AOPC-PU 中的比例增加及硬鏈結的比例增加，吸水率也隨之提升；而水解速率隨軟鏈結中的草酸含量提高而增加。最後，由分子量百分比及重量百分比的下降以及SEM 觀察結果證明，真菌Aspergillus sp.與Fusarium sp.對AOPC-PU 與ALPC-PU 具有分解的效果。經由NMR結構分析顯示AOPC-PU 以聚草酸酯基與醯胺基斷裂為主；ALPC-PU 則以聚乳酸酯基斷裂為主，其次為醯胺基斷裂，且聚草酸酯與聚乳酸在共聚酯的比例提高利於分解。

In our study, first, we use high-temperature melt poly-condensation polymerization to prepare a series of aliphatic oxalic based polycarbonate and aliphatic lactic based polycarbonate, and then use solution polymerization to prepare oxalic based polycarbonate polyurethane and lactic based polycarbonate polyurethane. The thermal degradation temperature and crystallization behavior were characterized by TGA and DSC, as oxalic and lactic content increase, the crystallinity of copolymer and thermal stabilility will be decrease. Tensile test results show the decrease in stiffiness and the increase in ductility as oxalic content increase, In addition, polyurethanes with high ratio of hard segment show high rigidity but poor ductility. The DMA analysis results also show that as the content of oxalate in the soft segment increases, the storage modulus decreases, and the mechanical properties of the polyurethane with high ratio of hard segment are more stable at high temperature. In the water absorption test, it was found that the proportion of oxalate in AOPC-PU and the proportion of hard chain increased, the water absorption rate also increased; and the hydrolysis rate increased with the content of oxalic acid content in the soft segment. Finally, the decrease of molecular weight percentage and weight remaining percentage and SEM images showed that the fungi Aspergillus sp. and Fusarium sp. had decomposition effects on AOPC-PU and ALPC-PU. The NMR structure analysis showed that the bond cleavage of AOPC-PU was mainly composed of polyoxalate ester group and amide group ; the bond cleavage of ALPC-PU was mainly composed of polylactide ester group, the second is amide group. Moreover, the increase in the proportion of lactic acid and polyoxalate in the copolyester facilitates decomposition rate.

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