Influence of laser irradiation on the optical and the mechanical properties of Makrofol-DE polycarbonate

The effect of IR laser irradiation on the optical and the mechanical properties of Makrofol-DE 1-1 CC polycarbonate films were investigated. Three hundred microns-thick films of Makrofol-DE 1-1 CC polycarbonate were irradiated with 0.00–10.40 J/cm² of Ga-As laser pulses, 904 nm, 5 W, and 200-ns pulse duration. Fourier transform infrared spectroscopy measurements showed that (CO) groups degrade under laser irradiation at the studied fluence range. The aliphatic and aromatic (CH) groups exhibited the same behavior, which can be attributed to nature of laser interaction with matter. The Makrofol samples exhibited degradation under the effect of laser irradiation up to 0.94 J/cm², where crosslinking mechanism started and continued until 7.07 J/cm². The refractive index had a minimum value at 0.94 J/cm² and maximum value at 7.07 J/cm² due to the degradation and crosslinking formation inside the sample, respectively. The decrease in elastic modulus, E, of Makrofol irradiated with 0.47–0.94 and 7.07–10.40 J/cm² indicates that the sample becomes more flexible, which results from the decrease in interatomic force constants. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011