In order to explore the emission characteristics of volatile organic compounds (VOCs) and different VOC components in airtight environments, polyvinyl chloride laminated plywood (PVC-P), melamine-impregnated paper laminated plywood (MI-P), water-based paint laminated plywood (WP-P) and unfinished plywood (UF-P) were tested as materials in 15 L small environment cabins. VOCs were collected after being sealed for 2 h, 4 h, 6 h, 8 h, 12 h, 18 h, 24 h and 30 h under different loading ratios (1 m2/m3, 1.5 m2/m3, 2 m2/m3, 2.5 m2/m3) and analyzed using a gas chromatography–mass spectrometer. The results show that VOCs gradually increased and tended to be saturated with the increase of time in an airtight environment. The saturation of veneered plywood was faster than unfinished plywood and the pollution degree of three kinds of veneered plywood from lowest to highest was in order of PVC-P, MI-P, WP-P. Aromatic hydrocarbons account for more than half of VOC concentration, and was most obviously affected by the loading ratios. Surfaced laminated plywood can reduce the emission of aromatic hydrocarbons, but also increases the amount of other compounds released. The concentration of VOC-components shows different characteristic curves at different loading ratios due to the influence of decorative materials.

Indoor air quality has become a focus of people’s attention. The emission characteristics and health risks of volatile organic compounds (VOCs) and the odor emitted from polyvinyl chloride (PVC) overlaid particleboard were investigated. A synthetic index-olfactory evaluation method was used to estimate the health risks of PVC, caused by VOCs and odor based on the technology of gas chromatography-mass spectroscopy/olfactometry. Olfactory analyses and instrument detection were implemented to identify the crucial odor-active compounds. The results demonstrated that the highest concentration of VOCs and highest odor intensity occurred in the initial stage. Overall, a total of 17 odor-active compounds, including aromatic hydrocarbons, ketones, esters, alcohols, and aldehydes, were identified from PVC, while aldehydes, ketones, and esters were the most harmful constituents. Pleasant, sweet, and spicy fragrances were the key odor characteristics. It was shown that covering of the surface could effectively prevent the release of VOCs and odors, and the increased thickness would raise the emission of VOCs when the change of the total odor intensities was low. Based on the evaluation, at room temperature of 23 °C ± 1 °C, it was suggested that PVC should be stored in a well-ventilated place (more than 0.5 m3m−2h−1) for at least 28 days before it is used indoors.

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The accurate measurement of wood dielectric properties and their relationship with many influencing factors are not only necessary for the study of other relevant wood properties, but also improve the wood dielectric moisture content detection method. In this study, the relationships between dielectric properties and frequency, as well as between moisture content and texture direction were analyzed. The results showed that the effect of the moisture content on the dielectric constant is significant. With increasing moisture content, the dielectric constant increased exponentially below the fiber saturation point. The effect of texture direction slightly exceeded that of the radial direction, and the change rate of the tangential direction above the fiber saturation point was higher than that of the radial direction. The relationship between the dielectric constant and frequency was related to the wood moisture content. The dielectric loss was approximately linear with the frequency below the fiber saturation point.

It is well known that the release of volatile organic compounds (VOCs) and odors from wood-based panels is harmful to human health. The VOCs emitted from decorative wood-based panels have been investigated generally, but information is limited regarding the key odor compounds that people find most irritating. In this experiment, particleboard coated with nitrocellulose lacquer was analyzed by gas chromatography coupled with mass spectrometry and olfactometry. Twenty odors were identified, which arose between 5 and 25 minutes. Most odorants from nitrocellulose lacquer–coated particleboard were aromatics, esters, and alcohols, whereas those from control (unvarnished) particleboard were aromatics, aldehydes, and esters. With an increasing ratio of air exchange rate to loading factor, the total VOCs concentration and the total value of odor intensity from nitrocellulose lacquer–coated particleboard declined. However, both increased as temperature and relative humidity rose. The fluctuation of total VOCs between different days tended to fluctuate more sharply when the temperature and relative humidity rose and when the ratio of air exchange rate to loading factor dropped. To accelerate the release of VOCs and odors and reduce their effects on humans, the optimum storing conditions for particleboard with a nitrocellulose lacquer after-production were 40°C, 60 percent relative humidity, and a 1.0-m3·h−1·m−2 ratio of air exchange rate to loading factor.