Monitoring Resin Cure During Particleboard Manufacture Using a Dielectric System
Keywords:
Particleboard, resin cure, UF, impedance, dielectric, pressing, densityAbstract
The hot press is a key piece of equipment in composite panel production. The press influences processing efficiency of the whole production line and the performance of products. The objective of this study was to nondestructively monitor the bonding development of particleboard during hotpressing using a dielectric system.
With all other variables held constant, laboratory particleboard pressed with 20-s closure time reached the initial conductivity peak and the conductance valley the earliest and had the highest value at the initial conductivity peak and the conductance valley versus other closing times studied. There were strong relationships between the impedance signal and panel strength developments. There were significant effects of panel thickness on the characteristics of impedance curve.
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