Applied Surface Science, Vol.445, 488-495, 2018
Micro-cracks on crosslinked Poly(dimethylsiloxane) (PDMS) surface treated by nanosecond laser irradiation
Surface morphology plays a critical role in the functionality of PDMS. In this work, micro-cracks were prepared on PDMS surfaces by nanosecond pulsed laser irradiation under ambient conditions. To fully investigate the resulting morphologies and the underlying processing mechanism, confocal microscopy, scanning electron microscopy (SEM), mu-Raman, 2D Raman and atomic force microscope (AFM) methods were employed to observe the laser treated PDMS samples. The results reveal that the micro cracks are the dominated morphology along the laser scanning routes, with lengths ranging from 56 mu m to 113 lm while the angles varied from 40 degrees to 90 degrees. To control crack propagation, the effect of laser fluence and scanning speed on the topography of the cracks was studied and a thermal-stress model was established to explain the propagation process. It is concluded that laser irradiation is an easy method of pattern PDMS surface with micro/nano dual scale structures. (C) 2018 Published by Elsevier B.V.