Get access

Flame retardant and mechanical properties of epoxy composites containing APP−PSt core−shell microspheres

Authors

  • ChunXia Zhao,

    1. State Key Lab of Oil & Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, People's Republic of China
    2. Department of Materials and Engineering, Southwest Petroleum University, Chengdu, People's Republic of China
    3. New Energy Center, Southwest Petroleum University, Chengdu, People's Republic of China
    Search for more papers by this author
  • YunTao Li,

    Corresponding author
    1. State Key Lab of Oil & Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, People's Republic of China
    2. Department of Materials and Engineering, Southwest Petroleum University, Chengdu, People's Republic of China
    3. New Energy Center, Southwest Petroleum University, Chengdu, People's Republic of China
    Search for more papers by this author
  • YunLiang Xing,

    1. Department of Materials and Engineering, Southwest Petroleum University, Chengdu, People's Republic of China
    Search for more papers by this author
  • Da He,

    1. Department of Materials and Engineering, Southwest Petroleum University, Chengdu, People's Republic of China
    Search for more papers by this author
  • Jie Yue

    1. Department of Materials and Engineering, Southwest Petroleum University, Chengdu, People's Republic of China
    Search for more papers by this author

ABSTRACT

Ammonium polyphosphate (APP)–polystyrene (PSt) core–shell microspheres (CSPs) were synthesized via in situ radical polymerization. The core–shell structure was confirmed by transmission electron microscope (TEM). The results of optical contact angle measurements demonstrated a significant improvement in hydrophobicity of the modified APP. The obtained APP–PSt CSPs were added into epoxy (EP) system with various loadings. Effects of CSP on flame retardancy, thermal properties, heat release rate (HRR), smoke production, and mechanical properties of EP/CSP composites were investigated by limiting oxygen index (LOI), UL-94 tests, thermogravimetric analysis (TGA), cone calorimeter, and tensile test. LOI and UL-94 indicated that CSP remarkably improved the flame retardancy of EP composites. TGA showed that the initial decomposition temperature and the maximum-rate decomposition temperature decreased, whereas residue yields at high temperature increased with the incorporation of microspheres. Cone calorimetry gave evidence that HRR, peak release rate, average HRR, and smoke production rate of EP/CSP composites decreased significantly. The morphology of char residues suggested that CSP could effectively promote EP to form high-quality char layer with compact outer surface and swollen inner structure. Tensile strength of EP was enhanced with the addition of CSP. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40218.

Ancillary