Dissertations in Forestry and Natural Sciences

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Taneli Väisänen: Effects of Thermally Extracted Wood Distillates on the Characteristics of Wood-Plastic Composites Figure 13. PTR-TOF 8000 used in studies II, III, and IV. In study II, the VOC emissions from seven different WPC deck boards were determined. One of the decks (LunaComp) was obtained from the manufacturer immediately after its production to investigate the changes in the VOC emissions during the first 41 days. Starting from the first day after the manufacture, the VOC emissions for this sample were characterized 11 times over a 41-day period to monitor the changes in the VOC emission rates. The sample was stored under laboratory conditions between the measurements. The ages of the six remaining decks were unknown, but they represented products that a consumer would use. As the WPC deck samples were prepared from different products, their shapes were irregular and dissimilar. Therefore, the VOC emission rates of these samples were determined with respect to their masses. In studies III and IV, the VOC emission measurements were carried out using the injection-molded specimens as samples. Five specimens of each material type were cut so that they had dimensions of 4.1 mm × 10.1 mm × 80 mm. The areas of the samples were determined so that it was possible to convert the obtained emissions into area-specific emissions rates. 82 Dissertations in Forestry and Natural Sciences No 222
Materials and methods The emissions were determined using 1.5 L glass vessels as the chambers. The glass vessels were prepared for the measurements by cleaning the inner surfaces with detergent and then rinsing them with distilled water. Furthermore, to ensure the purity of the chambers, the vessels were thermally cleaned by heating them in a force-convection oven at 120 °C for at least one hour. The tubes that introduce the air to the chamber and transport it to the PTR-TOF-MS system were installed on the metal lid that covered the glass vessels. The air (RH < 5%) that was introduced into the chamber with a flow rate of 0.3 L/min had been filtered with an active carbon/Purafil ® /HEPA filter. The air containing VOCs was then transported into the PTR drift tube via a polyether ether ketone (PEEK) tube at a total flow rate of 0.1–0.3 L/min. Before the samples were analyzed, the emissions from empty chambers were measured and this background was subtracted from the data during the analysis. Once the samples were placed in the chamber, the system immediately started to collect the data. As the VOC emissions could be observed online, each measurement was continued until the emissions of the compounds of interest stabilized. This took approximately 15 minutes for each material. After each measurement, the chamber was carefully flushed with purified air. The obtained data were analyzed using PTR-MS Viewer 3.1.0.27 software (Ionicon Analytik, Innsbruck, Austria). The concentrations were calculated by the program using a standard reaction rate constant of 2 × 10 -9 cm 3 s -1 molecule -1 . The trace gases were detected from the spectral peaks assuming that the molecules consisted only of hydrogen, carbon, and oxygen. The detection of gases was further supported by the literature data on the VOC emissions of wood materials and the matching of the isotope patterns, especially in cases where the detection was ambiguous. Table 4 lists the VOCs studied in each study. Dissertations in Forestry and Natural Sciences No 222 83
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PUBLICATIONS OF THE UNIVERSITY OF E
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Grano Oy Jyväskylä, 2016 Editors:
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ABSTRACT The use of raw materials d
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Universal Decimal Classification: 6
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Finally, I am grateful to my wife A
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TD-GC-FID/MS Thermal desorption/gas
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LIST OF ORIGINAL PUBLICATIONS This
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Contents 1 Introduction ...........
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1 Introduction The finiteness of cr
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Introduction A new and environmenta
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2 Wood-plastic composites By defini
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Wood-plastic composites additives u
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Wood-plastic composites Cellulose i
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Wood-plastic composites The propert
Page 33 and 34: Wood-plastic composites Figure 3. T
Page 35 and 36: Wood-plastic composites of lubrican
Page 37 and 38: Wood-plastic composites roughness a
Page 39 and 40: Wood-plastic composites Hosseinaei
Page 41 and 42: Wood-plastic composites the accessi
Page 43 and 44: Wood-plastic composites However, WP
Page 45 and 46: Wood-plastic composites A typical s
Page 47 and 48: Wood-plastic composites to fill the
Page 49: Wood-plastic composites absorption.
Page 52 and 53: Taneli Väisänen: Effects of Therm
Page 63 and 64: 4 Thermal processing of wood Therma
Page 65 and 66: Thermal processing of wood Figure 9
Page 67 and 68: Thermal processing of wood counterp
Page 69 and 70: Thermal processing of wood and the
Page 71 and 72: Thermal processing of wood and Miet
Page 73 and 74: 5 Aims and significance Despite the
Page 75 and 76: 6 Materials and methods Two types o
Page 77 and 78: Materials and methods heat energy f
Page 79 and 80: Materials and methods with the untr
Page 81 and 82: Materials and methods 6.2.1 Tensile
Page 83: Materials and methods 6.3 WATER ABS
Page 87: Materials and methods where Evoc is
Page 115 and 116: 9 Summary and conclusions In the pr
Page 117 and 118: Bibliography Abdolvahaba E, Lashgar
Page 119 and 120: Bibliography Ayrilmis N, Jarusombut
Page 121 and 122: Bibliography Cernansky R. State-of-
Page 123 and 124: Bibliography polypropylene composit
Page 125 and 126: Bibliography with odor assessments
Page 127 and 128: Bibliography La Mantia FP, Morreale
Page 129 and 130: Bibliography Mohan D, Pittman CU, a
Page 131 and 132: Bibliography Rinne J, Taipale R, Ma
Page 133 and 134: Bibliography Stark NM and Rowlands
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Bibliography Yeh S and Gupta RK. Im
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