InvestigatingThermal Behaviour of Glass fibre By Thermomechanical analysis

1. Sample holder Fibre Mainly into chopped fibre thermoplasticcomposites. Intrinsically recyclable InvestigatingThermalBehaviour of Glass fibre By Thermomechanicalanalysis Liu Yang, James Thomason Department of Mechanical and Aerospace Engineering University of Strathclyde (75 Montrose Street, Glasgow, G1 1XJ, UK) Furnace External stage Internal probe LVDT Recover and reuse as chopped fibre ? Mainly into continuous fibre thermosetcomposites Landfill no longer acceptable – but very difficult to recover continuous fibre Key Research Questions Challenging to recycle - so end-of-life = landfill ? • Mechanism(s) of strength loss during thermal recycling of glass fibre? • How to regenerate the fibre strength? • How to process recycled glass fibre? • How to improve temperature resistance of pristine glass fibre products? Glass Fibres: End-of-Life Scenario 4.3 MegaTons Glass Fibre GRP Recycling Projects Goals • Enable the development of cost-effective “drop-in” glass fibre and composite products based on recycled glass fibres with regenerated mechanical performance Development of TMA-Single Glass Fibre CLTE& Tg T Ramp T Isothermal Length Contraction At Elevated T 300°C 400°C 500°C F Ramp Single Fibre Tensile Test At Elevated T 20°C 700°C Conclusions • A TMA procedure has been successfully developed to probe thermal behaviour of glass fibre • CLTE=6.0 µm/(m·°C) below 300°C for boron-free E-glass fibre and Tg=759°C • Length contraction followed a logarithmic function of time at elevated T and implies that hyperquenched glass fibre undergoes structural relaxation • There should exist at least two mechanisms, thermal expansion and structural relaxation, which together account for overall thermomechanical behaviour of glass fibres. The former is related to the decrease of Young’s modulus at elevated temperatures and the latter is consider to be responsible for the increase of room temperature Young’s modulus after heat-treatment