نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه اتمی مولکولی، دانشکده‌ی فیزیک، دانشگاه علم و صنعت ایران، صندوق پستی: 13114-16846، تهران ـ ایران

2 پژوهشکده‌ی فوتونیک و فناوری‌های کوانتومی، پژوهشگاه علوم و فنون هسته‌ای، سازمان انرژی اتمی ایران، صندوق پستی 13-14399511، تهران- ایران

چکیده

تابش‌دهی لیزری پلیمرها سبب تغییر مشخصات ساختاری سطح و خواص نوری آن­‌ها می‌شود. پلی‌متیل‌متاآکریلات (PMMA) از جمله پلیمرهایی است که به‌دلیل دارا بودن ویژگی‌­هایی مانند ارزان بودن و زیست سازگاری، کاربرد فراوانی در بخش‌­های مختلف از جمله ساخت ابزارهای پزشکی ریزشاره دارد. هدف از این مطالعه، بررسی اثر تعداد پالس و شاریدگی‌­های بالاتر از حد آستانه لیزر گازکربنیک در ایجاد ریزساختارهای ایجاد شده بر روی سطح پلیمر PMMA و تغییر خصوصیات نوری آن، از جمله ضریب جذب، ضریب شکست و انرژی گاف نواری بوده است. نتایج به­‌دست آمده بیانگر شکل­‌گیری ریزساختارها بر روی سطح پلیمر PMMA در شاریدگی­‌های بالاتر از حد آستانه لیزر گازکربنیک است. در یک شاریدگی ثابت، با افزایش تعداد پالس­‌های برخوردی به سطح پلیمر تراکم و پهنای ریزساختارها بهترتیب افزایش و کاهش می­‌یابند. با افزایش شاریدگی در یک تعداد پالس برخوردی ثابت نیز روند مشابهی در ریزساختارها شکل می­گیرد. در بازه شاریدگیهای مورد بررسی در این مطالعه، 10-50 ژول بر سانتی­‌متر مربع، پهنای کانال‌­های ریزساختار بین 10-150 میکرومتر اندازه­‌گیری شده است. در تطابق با نتایج تجربی پیشین، نتایج این مطالعه بیانگر افزایش ضریب جذب، گاف نواری انرژی و ضریب شکست پلیمر PMMA پس از برهم‌­کنش با لیزر گاز کربنیک است.

کلیدواژه‌ها

عنوان مقاله [English]

Investigating the created microstructures and the induced changes in optical properties of PMMA by irradiation of a CO2 laser

نویسندگان [English]

  • S. Sohrabi 1
  • M. Vesal 1
  • H. Pazokian 2
  • M. Mollabashi 1
  • M. R. Rashidian Vaziri 2

1 Atomic and Molecular Group, Department of Physics, Iran University of Science and Technology, P.O.Box: 16846-13114, Tehran – Iran

2 Photonics and Quantum Technologies Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.Box: 14399511-13, Tehran – Iran

چکیده [English]

Laser irradiation of polymers leads to the change of structural and optical properties. Because of its favorable features like cheapness and biocompatibility, poly (methyl methacrylate) (PMMA) is one of those polymers that is in widespread use in different areas such as manufacturing medial microfluidic devices. The aim of the present study is to investigate the effects of the pulse number and the above-threshold fluences of the CO2 laser in the creation of microstructures on the surface of PMMA polymer and variation of its optical properties, like absorption coefficient, refractive index, and bandgap energy. The obtained results indicate the formation of microstructures on the PMMA surface at the above-threshold fluences of the CO2 laser. At a fixed fluence, the density and width of the microstructures increase and decrease by increasing the number of incident pulses, respectively. By increasing the fluence at a fixed number of incident pulses the same trend forms in the microstructures. In the range of investigated fluences in this study, between 10-50 J/cm2, the width of the microstructures is measured to be between 10-15 micrometers. Consistent with previous experimental results, the results of this study indicate the enhancement of absorption coefficient, bandgap, and refractive index of the PMMA polymer after interaction with the CO2 laser.

کلیدواژه‌ها [English]

  • Microstructures
  • PMMA Polymer
  • laser ablation
  • Pulsed CO2 Laser
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