The University of Sheffield
Department of Materials Science and Engineering

Fibre Reinforced Phenolic Composites with Improved Mechanical Performance

EPSRC research grant GR/J/47330

Summary of the final report

Principal Investigator: F R Jones

The excellent heat and fire resistance of glass reinforced phenolic composites, coupled to low smoke and toxic emissions make these ideal candidate materials for fire safety applications. However, their mechanical properties are generally inferior to those of other composite materials, such as those based on unsaturated polyester and epoxies. More advanced heat resistant matrices are uneconomical in off-shore, automotive and transport applications. The overall aims of this Link project was to achieve the mechanical performance of SMC and BMC based on unsaturated polyester resins, without sacrificing fire resistance. The objectives of the University Component were a) To assess the effectiveness of coupling agents and phenolic resin structure on the formation of a strong interface. b) To optimise the fibre surface coating for compatibility with phenolic resins.

The Industrial Collaboration

  1. Hepworth Minerals & Chemical Limited (HMC) manufacturer of phenolic resins.
  2. European Owens Corning Fiberglass Limited (OCF), manufacturers of glass fibre.
  3. TBA Composites Limited, manufacturer of automotive heat-shields, phenolic prepregs and moulding compounds.
  4. T & N Technology Limited, materials evaluator.
  5. Triton Plastics Limited, plastics moulder.

Conclusions

The project largely achieved its objectives and identified potential combinations of fibre sizing and resins to provide higher performance and more easily mouldable material. Formulations for optimum impact strength and strength were identified. The science component provided the confident selection of silane components. For example, the variability of performance of the epoxy type of silane could be attributed to hydrolysis during deposition onto the glass fibre. Amino silane provided coupling between the phenolic resin and the glass and phenolics of differing type were shown by high resolution XPS, at The Daresbury Laboratory, to have differing degrees of reactivity. The degree of deposition of phenolic resin onto the graded silane deposit, as shown by C 1s intensity, correlated well with the degree of adhesion assessed by bimatrix fragmentation.

Contact:

Prof. F.R. Jones,
Department of Engineering Materials,
University of Sheffield,
Mappin Street, Sheffield S1 3JD
Telephone: 0114 222 5477
Fax: 0114 222 5943