Influence of peroxide type on radiation-induced changes in static and dynamic mechanical properties of fluoro-vinyl-methyl-polysiloxane (FVMQ) elastomers
Radiation Physics and Chemistry, cilt.250, 2027 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 250
- Basım Tarihi: 2027
- Doi Numarası: 10.1016/j.radphyschem.2026.114283
- Dergi Adı: Radiation Physics and Chemistry
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, Compendex, EMBASE, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
- Anahtar Kelimeler: Energy dissipation, Fluorosilicone, Ionizing radiation, Mechanical properties
- Hacettepe Üniversitesi Adresli: Evet
Özet
This study examines the combined effects of curing peroxide type and ionizing radiation on the mechanical performance, viscoelastic behavior, and network structure development of fluoro-vinyl-methyl-polysiloxane (FVMQ) elastomers. FVMQ compounds were cured using dicumyl peroxide (DCP) and 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane (DPBH) at equal molar amounts, then exposed to ionizing radiation. The radiation-induced changes in gel fraction, crosslink density, mechanical properties, energy dissipation behavior, and network stability were systematically analyzed using tensile testing, cyclic compression tests, dynamic mechanical analysis, and sol-gel experiments. Crosslink density values were calculated through the Flory-Rehner swelling method and correlated with radiation dose and curing chemistry. The results show that ionizing radiation causes additional crosslinking in both elastomer systems at low and intermediate doses (≤200 kGy), which leads to increased stiffness, elastic modulus, and network density, along with a decrease in damping behavior. At higher radiation doses (250 kGy), deviations from this trend were observed, with partial reductions in crosslink density and gel fraction, as well as increases in the molecular weight between crosslinks, indicating the growing impact of radiation-induced chain scission and network disruption mechanisms. Throughout the entire radiation dose range, DCP-cured FVMQ elastomers showed higher gel fraction and crosslink density values, along with better structural stability, compared to the DPBH-cured system. These findings clearly demonstrate that the radiation response of FVMQ elastomers is strongly influenced by the initial network structure formed during peroxide curing. Considering both peroxide chemistry and radiation dose offers a logical framework for adjusting the mechanical and viscoelastic properties of FVMQ elastomers intended for use in radiation-prone environments.