Synthesis and Characterization of Novel Self-Colored PET (Polyethylene Terephthalate) by Step-Growth Polymerization Containing Dye based on 1,8-Naphthalimide Group

A novel self-colored polyethylene terephthalate (PET) was synthesized using a synthesized dye, 4-aminb-N-propanoic acid-1,8-naphthalimide. For this purpose, the prepared naphthalimide dye was added upon the polycondensation step and then a self-colored PET was prepared by step-growth polymerization. The characterization of synthesized self colored PET and naphthalimide dye were carried out using TLC, FTIR, (HNMR)-H-1, DSC, UV-visible and Fluorometery. Results indicated that, the novel fluorescent yellow-green PET with appropriate properties was obtained. The glass transition temperature of self-colored PET was 70 degrees C and it was measured by differential scanning calorimeter, which revealed that addition of dye to the chains of polymer did not affect the context of glass transition of polymer. UV-visible spectrum indicated that, 99 percent of dye was incorporated in polymer chains chemically. Furthermore, the intrinsic viscosity of self colored PET was 0.556 dl/g and molecular weight of polymer was around 35000 (g/mol) and measured using the viscometer technique.