Form-Stable Composite Phase Change Material With In Situ Constructed Phase-Changeable Polymer Adsorption Backbone

Abstract

The strategy of mixing adsorption skeleton to obtain composite phase change materials (CPCM) aiming to strengthen its thermal stability is confirmed to be simple but effective, and CPCM's thermal stability is directly proportional to the weight ratio of the adsorption skeleton. However, the processability and thermal storage density of which are inversely proportional to the content of adsorption backbone. To relieve the above contradiction, this paper proposed an in situ construction method for a phase-changeable adsorption backbone (PCPB). The in situ growth strategy avoided the processing difficulties caused by high stirring viscosity owing to the addition of large dosage of adsorption filler. Moreover, PCPB prepared via in situ polymerization of octadecyl methacrylate and 1,6-hexanediol diacrylate in PCM matrix presented obvious endothermic peak with latent heat of 89.5 J g⁻¹, which could undoubtedly alleviate the decay rate of CPCM's latent heat. In details, the maximum PCM loading percentage of PCPB could reach 50 wt%, and CPCM at this loading amount could reach latent heat as high as 149.7 J g⁻¹ and maintain form-stable without leakage even after thermal storage saturation. In addition, with the growth of PCPB in the phase change matrix, the 50% degradation temperature increased dramatically from 164.6°C to 350.0°C.