Impregnation of Wood with Microencapsulated Bio-Based Phase Change Materials for High Thermal Mass Engineered Wood Flooring

Abstract

Wood is a porous material that can be impregnated and have enhanced properties. Two species of hardwood, red oak (Quercus rubra L.) and sugar maple (Acer saccharum Marsh.), were impregnated in a reactor with a microencapsulated phase change material. The objective was to enhance the thermal mass of wood boards used as surface layers for engineered wood flooring manufacturing. Preliminary experiments were conducted on small samples in order to define suitable impregnation parameters, based on the Bethell cycle. Thin wood boards were impregnated with a microencapsulated phase change material dispersed into distilled water. Several cycles of pressure were applied. Heating storage of the impregnated wood boards was determined using a dynamic heat flow meter apparatus method. A latent heat storage of 7.6 J/g over 3 °C was measured for impregnated red oak samples. This corresponds to a heat storage enhancement of 77.0%. Sugar maple was found to be harder to impregnate and thus his thermal enhancement was lower. Impregnated samples were observed by reflective optical microscopy. Microcapsules were found mainly in the large vessels of red oak, forming aggregates. Pull-off tests were conducted on varnished samples to assess the influence of an impregnation on varnish adhesion and no significant influence was revealed. Engineered wood flooring manufactured with impregnated boards such as characterized in this study could store solar energy and thus improve buildings energy efficiency. Although wood is a material with a low-conductivity, the thermal exchange between the PCM and the building air could be good enough as the microcapsules are positioned in the surface layer. Furthermore, flooring is an area with frequent sunrays exposure. Such high thermal mass EWF could lead to energy savings and to an enhancement of occupant’s thermal comfort. This study aimed to characterize the potential of impregnation with MPCM of two wood species in order to make high thermal mass EWF.

Streamlined Life Cycle Assessment of an Innovative Bio-Based Material in Construction: A Case Study of a Phase Change Material Panel

“…This panel consists of three layers including an MDF and a high-density fiberboard (HDF) panel, as well as a plastic bag of PCM ( Figure 1) [54]. The properties of the functional units are listed in Table 1 [54,55]. Figure 1.…”

“…The properties of the functional units are listed in Table 1 [54,55]. [10], which is an international standard framework for conducting LCAs.…”

A thermal energy storage composite by incorporating microencapsulated phase change material into wood

“…The melting and cooling temperature of TES-WPC were 27.2 and 11.3 C, respectively, which indicated that the supercooling was negative for its application. Mathis et al 35 selected red oak (Quercus rubra L.) and sugar maple (Acer saccharum Marsh.) as the base materials to prepare TES wood.…”

Mechanical and Optical Properties of Thermochromic Reversible Waterborne Primer Film on Tilia europaea with 1,2-Benzo-6-diethylaminofluorane Based Microcapsules

“…The application of microcapsules to wood can generally be carried out through the impregnation treatment of microcapsule suspension into the pores of the wood [ 13 ], the physical mixing of microcapsules and adhesives into human-made boards [ 14 ], and the addition of microcapsules to the coating in advance through coating treatment [ 15 ]. But from the perspective of industrial production and “dynamic” color change decoration, the use of impregnation and adhesive may lead to problems such as high cost and large energy requirements, as well as uncertainty as to whether the microcapsules will maintain their shape and properties under heating and compressive stress [ 16 ].…”