Using phase change material to reduce the loss of quantum yield of fluorescent polymer when exposed to high temperature

Abstract

The quantum yields (QYs) of fluorescent materials decrease significantly as temperature rises, and this loss of QYs will become irreversible when exposed to high temperature for a long time. Herein, we prepare a zinc polyacrylate (ZnPA)/polyethylene glycol (PEG) composite using PEG-20000 as the phase change material (PCM) to reduce the loss of the QY of fluorescent ZnPA when exposed to high temperature. This composite is also a PEG-based form-stable PCM that is in solid state at 90 °C, solving the leakage issue of pure PEG in the melting process. Most important, the QY of ZnPA decreases by 50.4 % after a long period of thermal cycling, while that of the ZnPA/PEG composite does not decrease at all. This comparison indicates PEG-20000 can greatly reduce the loss of the QY of ZnPA when exposed to high temperature, in virtue of its excellent thermal energy storage density and negligible temperature change in the phase change procedures, as well as the rapid heat transfer between PEG-20000 and ZnPA.