Production and characterisation of wood-fibre insulation boards (WFIB) from hardwood fibres and fibre blends

Herstellung von Holzfaserdämmstoffen auf Laub- und Nadelholzbasis mit dem Fokus auf der Fasercharakterisierung, sowie der Ermittlung der physikalischen, mechanischen und biologischen Eigenschaften

“…As with the internal bond strength, only the rigid boards were tested, because the flexible mats are mainly used for between-rafter insulation, where there is hardly any capillary water absorption. In contrast to other stud-Veröffentlichung 3: Examination of various hardwood and softwood fibres for the usage in wood fibre insulation boards (WFIB) ies that found significantly higher water absorption -in addition to higher strength properties -for comparable hardwood boards (Zabihzadeh 2010, Imken et al 2021b, this study revealed significant differences both among the five hardwood species and among the softwood fibres. Due to this strong variation, no general differences between hardwoods and softwoods could be determined.…”

“…While boards from larch and oak only showed low strength among the pMDI-bonded boards, birch boards showed the second lowest value among pMDIbonded boards and the lowest value among the mats bonded by . This is in agreement with the study of Imken et al (2021b), which also reported low compression strength for birch WFIB. This finding was attributed to the higher bulk density of the birch fibres compared to the other fibres tested.…”

“…On the other hand, pine boards showed the second highest value (7.4 kg m -2 ) (Figure 7). Other studies reported similar water absorption for spruce boards ) and for birch boards (Imken et al 2021b) as in this study.…”

“…In contrast to the results of Imken et al (2021b)), no correlation with bulk density of the fibres (Figure 4) is discernible. Previous studies reported a decreasing thermal conductivity of insulation boards with decreasing density (Kawasaki et al 1998, Sonderegger andNiemz 2009).…”

“…Veröffentlichung 3: Examination of various hardwood and softwood fibres for the usage in wood fibre insulation boards (WFIB) The defibration conditions from Table 1 are based on findings from a previous study (Imken et al 2021a), while did not indicate it. A previous study using a disc gap of 0.6 mm revealed internal bond strengths of 1.1 kPa for birch and 6.0 kPa for spruce (Imken et al 2021b). Both values are slightly lower but comparable to those in this study.…”