In the present work, Laser induced Breakdown spectroscopy technique is used to investigate the laser induced plasma of PMMA in air. The optical emission of PMMA plasma is found quite intense and dominated by vibration...In the present work, Laser induced Breakdown spectroscopy technique is used to investigate the laser induced plasma of PMMA in air. The optical emission of PMMA plasma is found quite intense and dominated by vibrational band of CN molecules （violet band, B^2∑^＋ - X^2∑^＋） at 388.4 nm. The temporal response of the CN band emission is studied and found decay time 22 ns. The low decay time and small laser spot （34 × 32 μm^2） conf＇n-ms good thermal stability of PMMA. To get structural fingerprint of PMMA, Raman spectrum is recorded prior to the exposure to laser. Several sharp Raman peaks have been observed along with a very intense peak at 2,957 cm1 attributed to C-H stretching vibration. Post exposure Raman spectrum is also recorded to analyze the heating effect and re-deposition of ablated material.展开更多
文摘In the present work, Laser induced Breakdown spectroscopy technique is used to investigate the laser induced plasma of PMMA in air. The optical emission of PMMA plasma is found quite intense and dominated by vibrational band of CN molecules （violet band, B^2∑^＋ - X^2∑^＋） at 388.4 nm. The temporal response of the CN band emission is studied and found decay time 22 ns. The low decay time and small laser spot （34 × 32 μm^2） conf＇n-ms good thermal stability of PMMA. To get structural fingerprint of PMMA, Raman spectrum is recorded prior to the exposure to laser. Several sharp Raman peaks have been observed along with a very intense peak at 2,957 cm1 attributed to C-H stretching vibration. Post exposure Raman spectrum is also recorded to analyze the heating effect and re-deposition of ablated material.
