Orientated Nano-Composites: Relationships Between Nano-Structure and Mechanical Properties
Abstract
Epoxy nano-composites have been manufactured using a range of modifiers, including organoclays, silica nanoparticles and carbon nanotubes. The mechanical and fracture properties of these materials have been investigated, and the structure/property relationships discussed. Epoxy micro- and nano-composites have been manufactured using a range of layered silicate modifiers, including mica and nanoclays. The fracture toughness was increased by up to 150% with the addition of mica, but the material modified with the surface-treated clays generally showed a smaller toughening effect. In the present work, the degree of orientation of the particles was investigated using wide-angle X-ray scattering texture analysis. The platelets were found to be preferentially orientated parallel to the walls of the mould. However, fracture testing of specimens cut from orthogonal orientations showed that the fracture toughness was independent of specimen orientation. Hence, the orientation of the platelets has no effect on the fracture performance of silicate nanocomposites. The addition of nano-silica particles to the matrix of carbon fibre composites has been investigated. Both untoughened and rubber-toughened formulations were used, based upon an anhydride-cured epoxy. The addition of nano-silica leads to very significant increases in the toughness of the epoxy. The nano-SiO2 particles have an average particle diameter of 20 nm, and only a concentration of about 2% to 12% by mass of such nano-particles are needed to achieve significant improvements in the fracture performance. The toughening effect of carbon nanotubes and the effect of their orientation in adhesive joints has also been investigated. Firstly, attempts have been made to align nanotubes in-situ in an adhesive joint by applying an electric field.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 2004
- Accession Number
- ADA524325
Entities
People
- A. C. Taylor
- A. J. Kinloch
Organizations
- Imperial College London