Halogenfri flammehæmning af pultruderede polyester profiler

Halogen-free Flame Retarding of Pultruded Polyester Fibres

Summary and conclusions

Unsaturated polyester profiles for electronic and construction applications have been flame retarded by addition of halogen free flame retardants. The profiles were produced by pultrusion. Aluminium hydroxide, ammonium polyphosphate, magnesium hydroxide, nano-composites and expandable graphite were tested in different concentrations and grades.

Developments in rheology and morphology by the addition of the flame retardants to the polyester matrix have been studied.

The efficiency of the halogen free flame retardants was determined by LOI (Limiting Oxygen Index) and UL-94.

X-ray analysis showed the distribution of the glass fibres in the profiles. XPS-analysis and SEM (Scanning Electron Microscope) were used to characterise the profiles.

The best flame retarded properties were achieved by addition of aluminium hydroxide (approx. 50 %) and ammonium polyphosphate (approx. 5 %). Profiles with this formulation passed the DIN 5510-S4 standard. The highly filled profiles could be used in electronic applications, but due to deterioration of the mechanical properties aluminium hydroxide and ammonium polyphosphate could not be used to flame retard profiles for construction applications.