Reinforcement of epoxy resin composites with fluorinated carbon nanotubes

Epoxy resin (diglycidyl ether bisphenol-A type) polymer composites with added unmodified and fluorinated carbon nanotubes (CNTs) were studied by FTIR, TGA, DSC and electron microscopy. Composites tensile and flexural strength were measured. CNTs fluorination markedly (by a factor of 2.26) increased its specific surface. Fluorination did not influence CNTs thermal stability below 260 degrees C and did not worsen thermal stability of filled composites. Insertion of 0.1 wt% of CNTs fluorinated at 150 degrees C into polymer matrix resulted in the composite tensile strength increase to 89.6 +/- 4.1 MPa (35% increase as compared with unfilled composites). Flexural strength of composite filled with 0.2 wt% fluorinated at 150 degrees C CNTs was increased to 199.7 +/- 4.8 MPa (+58% as compared with unfilled composite). Obtained reinforcement values exceeded all the available literature reinforcement data reported for epoxy composites based on epoxy resins similar to used in the current project. Unmodified CNTs were less effective in composite tensile and flexural strength improvement as compared with fluorinated CNTs. Insertion of fluorinated CNTs into a polymer matrix increased glassy temperature and did not influence the composites thermal stability. Surface of composites cuts was studied by electron microscopy technique. The reinforced composites can be applied in several industries: aviation, automotive, wind turbine propeller blades, for producing yachts and boats etc. (C) 2014 Elsevier Ltd. All rights reserved.