HS-SPME and GC-MS for the analysis of odorous constituents from heat-treated rubberwood and the chemical change of heat-treated rubberwood by XPS analysis

With the increase in heat-treated rubberwood used in interior decoration materials, the odorous constituents have attracted people's attention. In this study, a headspace solid-phase microextraction method coupled with gas chromatography-mass spectrometry was employed to analyze the odorous constituents released from heat-treated rubberwood and the gaseous components from the heat treatment process. The results showed that the odorous constituents were classed into aldehydes, esters, ketones, acids, alcohols, phenols, alkanes, aromatics, and others. During the four-month test period, the emissions of aldehydes (47.08% and 65.66%) were the most dominating compounds in VOCs emission from F180 degrees C and F200 degrees C. The changes in chemical structure of rubberwood before and after heat treatment were investigated by X-ray photoelectron spectroscopy. It was found that the O/C ratio of rubberwood decreased from 0.52 to 0.44 after heat treatment with increasing temperature; the contribution of C-1 and C-2 peaks is more important than C-3 and C-4. With increasing treatment temperature, the C-1 contribution of rubberwood samples increased from 34.37 to 42.47%, whereas the C-2 decreased markedly from 55.50 to 48.24% and the C-3 began to decrease at higher temperature. These results corresponded to variations observed from the gas chromatographic mass spectrometry results of heat-treated rubberwood.