本研究使用1,6-己二胺(1,6-hexamethylenediamine,HMDA)、4,4’-氧化二苯胺(4,4- Oxydianiline,ODA)、1,4-双(4-氨基苯氧基)苯(1,4-bis(4-aminophenoxy)benzene,pBAB)、4,4’-(4,4’-異丙烯基二苯氧基)双(鄰苯二甲酸酐) [4,4’-(4,4’-Iso-propylidene diphenoxy) bis(phthalic anhydride),BPADA]為原料,通過改變兩種不同二胺單體的比例,並以隨機共聚合物(random compolymers)與嵌段共聚合物(block copolymers)之合成方法,來改變聚醯亞胺之化學結構。觀察並研究以不同的二胺比例與排列方式的差異性對所合成之聚醯亞胺的物化性質、熱性質與機械性能之影響。由熱性質與機械性質數據顯示嵌段共聚合物的方式比隨機共聚合物有較佳的加工性,且其在HMDA含量25%時較能提升機械性能。並且在本研究之電紡條件下,用pBAB聚醯亞胺以嵌段共聚合物的方式擁有較完整的微米級纖維。
1,6-Hexamethylenediamine (HMDA) is utilized to synthesize polyimide copolymers based on bisphenol-A dianhydride and 4,4-Oxydianiline (ODA) or 1,4-bis(4-aminophenoxy)benzene (pBAB). The purpose of this study is to modify the processability of aromatic polyimides for specialty textiles. Partially aliphatic polyimides containing an aliphatic diamine HMDA are synthesized via random and block copolymerizations. Variations in the aliphatic content produced a series of polyimides having different glass transition temperatures, thermal stability, mechanical properties, and processing characteristics. Each copolymer is characterized by its chemical structure, molecular weight, melt index, thermal and mechanical properties. Based on the experimental results, polyimides synthesized with 25% HMDA have better mechanical properties than other contents, and block copolyimides have better processability with higher melt index than random copolymers. Also, the tensile strength and Tg of polyimides synthesized with pBAB are lower than those synthesized with ODA, this could be attributed to the increased flexibility in the polymer chain with longer phenylene ether units.