Effects of Acid Dyes on Crystallization and Mechanical Porperties of Melt-Reprocessed Nylon 66

摘要

Nylon fibers dyed with different types of acid dyes were melt reprocessed using a compression-molding machine.The crystalline structure and mechanical properties of the melt-reprocessed nylon were experimentally evaluated.It was found that metal complex acid dyes showed much more distinct effects on the structure and mechanical properties of melt-reprocessed nylon than nonmetallized acid dyes.They decreased the crystallization rate of the molten nylon and reduced its crystallinity.They also reduced the imperfect form I structure in the crystalline region.Compression-molded nylon samples showed inferior mechanical properties in the presence of metal complex acid dyes.The coordinate bonds between the Cr~(3+) ions and amide groups are possibly formed in melt-reprocessed nylon,which could be the reason for the changes in the structure and properties of melt-reprocessed nylon.