Luminescent Characteristics of Fluorescent Organic Pigments Doped Recycled Polyethylene Thin Films Deposited by Ultrasonic Spray Technique at Low Temperature

Fluorescent organic pigments (FOP´s) doped recycled polyethylene (PE) thin films were synthesized by using the ultrasonic spray technique at low temperature. With the objective of minimizing the environmental impact caused by plastic wastes, a new recycling scheme for the fabrication of luminescent polymeric thin films was designed. The recycled plastic bags of Low Density PolyEthylene (LDPE) were used as hosts for the FOP's. The process consisted of spraying an organic solution of LDPE on glass substrates. Later the FPO`s solution was sprayed on top of the LDPE thin films. Several deposition conditions were varied (deposition time, precursor concentration and substrate temperature) to form homogeneous and uniform films. The substrate temperature was low (180°C) in order to avoid thermal degradation of the polymer, as revealed by infrared spectroscopy. These films were doped with different FOP's. Emissions such as blue light emission (λ=434 nm), orange light emission (λ=503 nm) and green light emission (λ=503nm) were obtained by photoluminescence. These FOP´s were mixed to obtain white light emission polymeric films. The thicknesses were close to 1µ. According to Scanning Electronic Microscopy, the LDPE films consisted of small-superposed clusters and the FOP´s were adhered of them. The optical transmission was shown in the 60-80% range.

 

Acknowledgments

The authors acknowledge the financial support from SIP-IPN and CONACyT through the scientific research projects (Grant Nos. 20140458, 20140459, 20131915, 20130236, 20130153, 20121399, 129227).