Bark Thermal Insulation Panels: An Explorative Study on the Effects of Bark Species

Abstract

Tree bark is a byproduct of the timber industry which accrues in large amounts, because approximately 10% of the volume a log is bark. Bark is used primarily for low-value applications such as fuel or as a soil covering material in agriculture. Within the present study, thermal insulation panels made from larch, pine, spruce, fir and oak tree bark with different resins (urea formaldehyde, melamine formaldehyde, Quebracho, Mimosa) as a binder are discussed. Also, the properties of panels made from larch bark mixed with industrial popcorn are investigated. The physical-mechanical properties of the panels, which are dependent on panel density, bark species, resin type, resin content and particle size, are analyzed. The bark species has a minor effect on the mechanical characteristics of the panels, while the compression ratio is important for the panel strength, and hence, barks with lower bulk density are preferable. Under laboratory conditions, panels made with green tannin resins proved to have adequate properties for practical use. The addition of popcorn is a means to lower the panel density, but the water absorption of such panels is comparably high. The bark type has a minor effect on the thermal conductivity of the panels; rather, this parameter is predominantly affected by the panel density.

Larch Bark as a Formaldehyde Scavenger in Thermal Insulation Panels

“…For this study, the perforator method, mostly used in industry, and the desiccator method [ 25 ] were chosen. This study follows the previous research of [ 12 , 22 , 26 , 27 ].…”

“…The resin type significantly influences the TS and WA [ 27 , 40 ] reported about the increase in TS and WA when using tannin-based adhesives. For both density ranges, all the tannin-bonded samples recorded the highest values for thickness swelling ( Figure 6 ) after 24 h of water immersion (18.5%, 11%, and 12%) for 8%, 12%, and 16% glue amounts (300 kg/m 3 ) and 26%, 16%, and 13% at a density of 500 kg/m 3 .…”

“…The values of thermal conductivity were not reported in this study, because they were described in the research of [ 27 ].…”

An Assessment of the Thermal Behavior of Envelope Surface Coatings with Different Colors

“…In recent years, increasingly more emphasis has been placed on the rational use of energy and waste management in building materials [ 1 , 2 , 3 , 4 ]. One of the main issues of energy saving involves heat protection of external building partitions [ 5 ]. The most frequently undertaken action to reduce energy consumption is to increase the thermal resistance of external partitions—improving the insulation of partitions by increasing the thickness of the thermal insulation [ 6 ].…”

Advances in Wood Composites III

“…Bark panels have recently received some attention and the performance of composites made of various bark species were investigated by Kain et al [ 12 ]. Insulation panels were made and a variety of parameters were examined, such as bark species, resin content, resin type and density.…”