Comparative Evaluation of Novel Heterocyclic Azo Disperse Dyes on Polylactic Acid and other Hydrophobic Fibers

Abstract

Some novel heterocyclic azo disperse dyes were synthesized from 2-aminothiophenes which were prepared from cyanoacetates and a range of 1,3- dicarbonyl compounds such as, oacetoacetotoluidide, 4-chloroacetoacetanilide, and o-acetoacetanisidide using the Karl-Gewald one-pot technique. The 2-aminothiophenes were the major precursors for the series of dyes which were used in the work. The dyes were applied to various hydrophobic fibers such as polylactic, polyester and nylon. The dyes gave results comparable to those of conventional disperse dyes of similar composition. The exhaustion and light fastness and other relevant data were particularly good on the polylactic acid fiber in contrast to some widely reported data. Dyeing behaviour of (PLA) fibre also showed that at slightly higher temperature, the colour strength of PLA was higher as compared to other fibers. The dyes are therefore well recommended especially for application on PLA (polylactic acid) and polyester, where it’s cost of production from simple and available starting materials are an obvious and attractive advantage.