Thermal and environmental stability of poly(4-ethynyl-p-xylylene-co-p-xylylene) thin films

The aim of this paper was to test the thermal and environmental stability of poly(4-ethynyl-p-xylylene-co-p-xylylene) thin films prepared by chemical vapor deposition (CVD) and to optimize the reaction conditions of the polymer. Fourier transformed infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and fluorescence microscopy were employed to investigate the stability of the reactive polymer coatings in various environmental conditions. Chemical reactivity of the thin films were then tested by Huisgen 1,3-dipolar cycloaddition reaction (click reaction). The alkyne functional groups on poly(4ethynyl-p-xylylene-co-p-xylylene) thin films were found to be stable under ambient storage conditions and thermally stable up to 100 degrees C when annealed at 0.08 Torr in argon. We also optimized the click reaction conditions of azide-functionalized molecules with poly(4-ethynyl-p-xylylene-co-p-xylylene). The best reaction result was achieved, when copper concentration was 0.5 mmol/L, sodium ascorbate concentration to copper concentration was 5:1. In contrast, the azide concentration and temperature had no obvious effect on the surface reaction. (C) 2015 Joerg Lahann. Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. All rights reserved.