Thermal, dosimetric and thermo-mechanical characterization of ABS and PLA polymer materials via plastic injection molding for innovative bolus materials in radiotherapy applications


ŞAHİN T., Çavdar Karaçam S., TUNÇMAN D., ŞAHİN Ş., ERGEN Ş. A., Çolpan Öksüz D., ...More

Radiation Physics and Chemistry, vol.223, 2024 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 223
  • Publication Date: 2024
  • Doi Number: 10.1016/j.radphyschem.2024.111901
  • Journal Name: Radiation Physics and Chemistry
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, INSPEC, Metadex, Pollution Abstracts, Civil Engineering Abstracts
  • Keywords: ABS, PLA, Radiation dosimetry, Radiotherapy, Thermal properties
  • Kocaeli University Affiliated: Yes

Abstract

The impact of radiation on polymer materials, and consequently on their mechanical and physical properties, is a burgeoning field of research. This research assesses the dosimetric, mechanical, and thermal characteristics of Acrylonitrile Butadiene Styrene (ABS) and Polylactic Acid (PLA) materials developed through plastic injection molding as possible alternatives to commercial bolus used in radiotherapy. The materials were thoroughly compared with the commercial bolus material, EXAFLEX, by various tests such as Hounsfield Unit (HU) Analysis, Radiation Transmittance, Thermogravimetric Analysis (TGA), Thermomechanical Analysis (TMA), and Fourier Transform Infrared Spectroscopy (FTIR). The research indicates that ABS and PLA materials have similar radiological qualities to EXAFLEX, showing constant surface and accumulation area doses. Minor differences are seen deeper inside the phantom, indicating a stable tissue equivalency. ABS demonstrated strong resistance to radiation-induced chemical modifications, but PLA exhibited susceptibility to molecular changes. The TMA findings showed that radiation caused a decrease in softening temperatures and an increase in the coefficient of thermal expansion for both ABS and PLA, indicating changes in their thermal stability and mechanical characteristics after irradiation. The study highlights the potential of ABS and PLA materials made through plastic injection molding as efficient and safety substitutes for commercial bolus materials, particularly for large area irradiation. This requires more research into their clinical uses and consequences.