SYNTHESIS AND ELECTROSPINNING OF A NOVEL FLUORESCENT POLYMER PMMA-PM FOR QUENCHING-BASED OPTICAL SENSING

ABSTRACT

This work presents the synthesis of a new fluorescent polymer and its applicability for optical sensing using the electrospinning technique for the fabrication of nanofibrous membrane sensors. A new fluorescent monomer was first synthesized by coupling reactions between methacryloyl chloride and a pyrene derivative, 1-pyrene butanol. Fluorescent polymers containing different ratios of pyrene were then obtained by the copolymerization of this monomer with methylmethacrylate using 2,2′-azobisisobutyronitrile as the initiator. These polymers show distinct and well-defined fluorescence that is characteristic of the pyrene chromophores. Quenching-based optical chemical sensors were then fabricated by the electrospinning technique. The preliminary results show that these sensors have an order of magnitude higher sensitivity to the target analyte 2, 4-dinitro toluene than sensors formed from continuous thin films. This is believed to be due to the higher surface area to volume ratio of the electrospun nanofibrous membranes. The quenching behavior follows Stern-Volmer bimolecular quenching kinetics. The synthesis, characterization, electrospinning fabrication, and sensing capability of these polymers are discussed.

Keywords:

• Electrospinning
• Fluorescent polymer
• Optical sensing

ACKNOWLEDGMENTS

Financial support from the U.S. Army is gratefully acknowledged. The authors thank Professor C. Sung and Ms. B. Kang for the SEM images. This work is dedicated to Professor S. K. Tripathy.