Eco-friendly wood plastic composites with biomass-activated carbon-based form-stable phase change material for building energy conversion

Phase change materials (PCM) can store heat energy through the process of phase change and keep the ambient temperature in a comfortable range, thus reaching the aim of energy conservation and emission reduction. To improve the latent heat capacity, activated carbon (AC) with a dendritic pore structure was used as the carrier, and polyethylene glycol (PEG) was loaded by vacuum adsorption method. A dendritic pore structure with a nesting pattern of macropores, mesopores, and micropores was formed through the steam activation process of waste wood chips, leading to a high load capacity (70%) and uniform distribution, which showed high heat storage performance (ΔHm reached 116 J/g). Then the form-stable phase change material with satisfactory performance (AC/PEG-70) was combined with wood flour/ high-density polyethylene (WF/HDPE) through blending and hot pressing to fabricate phase change heat storage wood-plastic composite material (A-WPC). When the AC/PEG-70 content was 50%, the elongation at break increased by 167% (20%), and the rigidity of the material enhanced. ΔHm of A-WPC-50 was 19 J/g, undoubtedly at this point, achieving the expected thermal performance. Thus, we prepared an eco-friendly wood-plastic composite with high latent heat capacity and high stability by using the dendritic pore structure of biomass activated carbon-based form-stable PCM, which has great significance in promoting energy conservation and emission reduction, responding to green technological innovation and promoting the development of the green and low-carbon industry.