Investigation on interfacial interaction and thermal properties of flame retarded wood-plastic form-stable phase change material

Abstract

ABSTRACT In this study, using the polyethylene glycol-4000(PEG) as functional phase for heat energy storage, however, the organic PEG has an interfacial combination problem with surrounding materials and liquid PEG leakage problem. To solve the problem, the porous wood flour was chosen as a matrix, which has suitable pore size and the hydroxy on wood flour has interaction with the hydroxyl group on PEG and the shape-stabilized phase change materials (WF-s-PEG) were fabricated by vacuum impregnation method. Then WF-s-PEG was mixed with polypropylene to prepare wood-plastic phase change materials. Moreover, the expandable graphite (EG) was introduced to prepare flame retarded phase change materials (FR-PCM), which was rarely reported previously. Chemistry properties of porous phase change material were measured by FT-IR, XRD and scanning electron microscopy. The results showed that PEG physically was filled in the porous of WF. FR-PCM had higher enthalpy (164 J/g) and phase change temperature (60℃). With the EG loading, the thermal conductivity and flame retardancy were improved. Meanwhile, thermal stability and charring ability were enhanced by thermal gravimetric analysis. FR-PCM could pass a UL-94 V-0 rating with 18.2% EG. The CONE data further confirmed that the FR-PCM had good flame retardancy.