Properties of hemp fibre reinforced
unsaturated polyester composites following exposure to accelerated weathering
conditions have been studied. Exposure to ultraviolet (UV) radiation and UV radiation plus
condensation resulted in immediate loss in weight which stabilised following
prolonged exposure times. The same exposure led to initial decline in tensile
properties of hemp fibre composites, but the decline in properties also
stabilised following prolonged exposure and these materials seemed to perform
fairly well in these conditions. The decline in strength and modulus was quite
similar, unlike immersion in water where the reduction in modulus was more
pronounced than the reduction in strength. Discolouring of composites following
exposure to these conditions was identified as an issue with these composites.
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