Abstract:

Through analyzing formaldehyde release equation in desiccator, factors influencing formaldehyde release from wood products were discussed and checked. The relationship of the values was also compared determined by 10 L glass desiccator and 40 L acrylic desiccator method. The results showed that the formaldehyde release equation accurately represented the behavior of formaldehyde release in desiccator. The formaldehyde concentration was inverse ratio to the water volume and formaldehyde concentration gradually increased while the surface area of water increasing. For samples with same ratio of edge area to surface area, a good linear relationship was existed between the two desiccator methods, and the desiccator values determined by 40 L desiccator method was 3.5～3.9 times of that determined by 10 L desiccator method. But for samples with different ratio of edge area to surface area, there was no comparability between 10 L and 40 L desiccator values. The formaldehyde emission rate from the edge was much faster than the surface of the panel. For particleboard and MDF, the formaldehyde emission rate from the edge was about double of that from the surface of panel. For DMDF, more than 87% formaldehyde emitted from the edge of the panel. For plywood, about 40% formaldehyde emitted from the edge of the panel.

Key words: Desiccator method, Formaldehyde emission, Formaldehyde release equation