Synthesis and Characterization of a Novel Self-colored Fluorescent Polycarbonate Urethane based on the 1,8-Naphthalimide Group

Abstract

The synthesis of a novel self-colored polyurethane (PU) is described using 4-amino-N-propanoic acid-1,8-naphthalimide dye. To synthesize the self- colored PU, the dye was added to the PU prepolymer at the chain extension step. PU and self-colored PU were characterized by using Fourier transform infrared spectroscopy (FTIR), UV-visible spectroscopy and Fluorometry. The thermal behavior of the PU and self-colored PU were investigated by differential scanning calorimetry (DSC). The spectra indicated that the addition of dye to the polymer chain did not affect the glass transition temperature (Tg = -39 °C). Tensile strengths and Young’s modulus of the samples were assessed using a tensile strength test; they revealed that addition of the dye to the polymer structure enhanced the Young’s modulus and increased the mechanical strength of the PU. X-ray diffraction (XRD) was used for evaluation of the crystal phase of the polymer; it revealed that both components were amorphous.