Photo-Cross-Linkable Polymers with Thermally Degradable Property

Polymers having both epoxy moieties and thermally cleavable tertiary ester moieties in the side chain were synthesized and characterized. On UV irradiation, polymer films containing photoacid generators (PAG) such as 9-fluorenilideneimino p-toluenesulfonate (FITS) and triphenylsulfonium triflate (TPST) became insoluble in tetrahydrofuran. The insoluble fraction of the irradiated films was increased by postexposure-baking at 90 °C if FITS was used as a PAG. When the cross-linked polymer films were baked at 160−180 °C, they became soluble in methanol. The effective baking temperature was dependent on the type of PAG used and on the polymer structure. Thermal degradation of the photochemically induced network polymers was studied by FT−IR spectroscopy, TGA analysis, and film thickness changes.