| 摘要 |
In the present invention, an aramid copolymer is prepared by dissolving, in an organic solvent, (i) one aromatic diamine selected from para-phenylenediamine, cyano-para-phenylenediamine and a mixture of para-phenylenediamine, and cyano-para-phenylenediamine and (ii) tetramethylenediamine which is an aliphatic diamine; adding terephthaloyl dichloride in the organic solvent in which the aromatic diamine and tetramethylenediamine are dissolved; and copolymerizing the resultant. The present invention is characterized by using tetramethylenediamine, which is an aliphatic diamine, instead of some aromatic diamine dissolved in the organic solvent. Since the present invention includes tetramethylenediamine, as an aliphatic diamine, having a structure and sizes similar to those of a benzene ring in replacement of some aromatic diamine ingredients, flexibility of a polymer molecular chain is increased so that an elongation degree of a fiber is greatly enhanced. Also, by minimizing decline in liquid crystal properties of a polymerizing solution due to difference in structures and sizes of aromatic diamine and tetramethylenediamine dissolved in the organic solvent, decline in strength of a fiber is prevented. Therefore, the copolymer aramid fiber prepared according to the present invention has greatly increased elongation degree without in decline in strength. |
