Effect of tin filler composition on porosity in tin-polydimethylsiloxane composites

Abstract A high porosity in radiation shielding material led to radiation penetrating, raising the exposure risk for radiation workers, patients, and the public. Thus, this study is designed to observe and evaluate the morphology and structure of a composite material and its porosity. Tin-PDMS-based composite is prepared by dispersing pure tin powder into PDMS polymer liquid at different weight percentages of tin powder, at 10 %, 20 %, 30 %, 40 %, 50 %, and 60 %. It was analysed under Field Emission Scanning Electron Microscopy (FESEM), and energy dispersive X-ray (EDX) and evaluated with ImageJ software. FESEM showed an intact composite structure with low porosity, Fourier Transform Infrared Spectroscopy (FTIR) analysis verified that tin had been successfully incorporated into the PDMS matrix. The material’s compositional integrity was confirmed by EDX analysis, which revealed a progressive increase in tin content along with a decrease in oxygen and silicon concentrations. With 60 % tin filler showing the maximum porosity of 0.34 %, the porosity measurements showed a small rise with increasing tin compositions. 20 % tin powder composite exhibited the highest pore size (0.031 µm), indicating that pore size doesn’t increase with higher metal powder content. Therefore, the novelty of this study lies in the optimisation of tin dispersion within PDMS to achieve an effective balance between attenuation capability and material integrity and to ensure that the composite is compact and can attenuate the radiation beam successfully.