In the present study, an amphiphilic diblock copolymer made of poly(epsilon-caprolactone) (PCL) and poly(tetrahydrofuran) (PTHF) was synthesized via ring opening polymerization (ROP) of epsilon-caprolactone (CL) and tetrahydrofuran (THF) with rose bengal (RB) as a bridging agent in a two-step process. In the first step, RB-PCL was synthesized by the ROP of CL, while in the second step the diblock copolymer was prepared by the ROP of THF with RB-PCL moiety as a chemical initiator in the presence of phthalic anhydride (PAH) as a co-monomer. The diblock copolymer was characterized by H-1 and C-13 nuclear magnetic resonance (NMR) spectroscopy, Fourier transform infra red (FTIR) spectroscopy, UV-visible spectroscopy, fluorescence spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM), gel permeation chromatography (GPC) and EDX studies.