Due to increasing usage of natural renewable materials, the cultivation and production of hemp (its fibres and shives) is also expanding. Hemp fibres and shives have already found applications in insulation and chipboard production, although in these they are mainly used only as additives in small quantities. Since hemp shives can be used to make a composite with suitable strength as well as a composite with good insulating properties, we wanted to test the possibilities of making a structural insulating composite or SIP board which would be of use in panel systems applications. Such composites consist of insulating cores (EPS, XPS or PUR) surrounded on both sides by structural panels (OSB, plywood or chipboard). In the first part of our study we have produced four single-layer (8 mm) structural panels of different densities using hemp shives and MUF resin and four insulating panels (50 mm) using different portions of hemp shives and PUR foam. For structural panels we have determined the mechanical properties, while for insulation panels their thermal conductivity. From the obtained data, we then selected a structural and insulating panel with the optimal mechanical/insulating properties, and based on this data constructed the SIP composite for which we determined the thermal conductivity and compressive strength. We found that a density of approx. 700 kg/m3 is most suitable for structural panels. We also found that the thermal conductivity of the insulating cores increases with the addition of hemp shives, and therefore we used an insulating panel with a density between 75 and 100 kg / m3 (25% of hemp shives). The compressive strength of the SIP composite was 4.93 Mpa, and its thermal conductivity was 0.0514 W/mK.
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