Effect of CO2 laser radiation on the surface properties of polyethylene terephthalate

The surfaces of polyethylene terephthalate (PET) obtained by irradiation wi th a CO2 pulsed laser in air were studied. The complicated microstructures using various laser wavelengths were observed by scanning electron microsco py (SEM). The changes in chemical and physical properties of the irradiated PET surface were investigated by attenuated total reflectance infrared spe ctroscopy (ATR-FTIR) and contact angle measurements. ATR-IR spectrum showed that the crystallinity in the surface region decreased due to laser irradi ation. The water drop contact angle also decreased with increasing of laser pulses. The density of peroxides formed on the irradiated PET surface were determined by iodide method. (C) 1999 Elsevier Science Ltd. All rights res erved.