A Comprehensive study of the exposure and energy absorption buildup factors in some polymer composites for point isotropic Source, including the effect of bremsstrahlung

•The exposure and energy absorption buildup factors of different polymer composites were calculated for photon source.•Various polymer composites such as; SiW, PHEMA-WO3, CaWO4, EWO3, BaTiO3, PbCl2 were evaluated.•Monte Carlo model validated by comparing uncollided flux and exposure buildup factor with published data.•Buildup factors vary by incident photon energy and penetration depth, BaTiO3 has the highest EBF and EABF while SiW has the lowest.•Considering bremsstrahlung effect increases exposure buildup factor, especially at energies above 3 MeV. The exposure (EBF) and energy absorption buildup factors (EABF) of different polymer composites (SiW, PHEMA-WO3, CaWO4, EWO3, BaTiO3, PbCl2) has been investigated for photon isotropic source with the energy range of 0.015–15 MeV and the penetration depth of 1–10 mean free path(mfp). Furthermore, the contribution of bremsstrahlung effect on selected polymer composites EBF has been discussed. Simulations were performed by MCNPX Monte Carlo code. Model validation was carried out by comparing theoretical uncollided flux and EBF of water with similar published data. The results indicate that EBF and EABF values are dependent on the incident photon energy and the depth of penetration. The maximum and minimum values of EBF and EABF are related to BaTiO3 and SiW, respectively. Moreover, it is observed that considering bremsstrahlung increases values, especially at energies greater than 3 MeV.