Preparation and characterization of palmitic acid/polymer composite phase change materials supported with cross-linked poly(limonene-co-ethylene glycol dimethacrylate) copolymers for low-temperature thermal applications

• Published in: Reactive & functional polymers 2024-05, Vol.198, p.105884, Article 105884
• Main Authors: Kekevi, Burcu, Mert, Hatice Hande, Mert, Mehmet Selçuk, Mert, Emine Hilal
• Format: Article
• Language: English
• Subjects: Latent heat storage; Limonene; Palmitic acid; Phase change material
• ISSN: 1381-5148
• DOI: 10.1016/j.reactfunctpolym.2024.105884

Limonene-based polymers have a growing interest as being renewable source-derived materials. Here, highly cross-linked porous polymers were synthesized by free radical copolymerization of water-in-oil (w/o) high internal phase emulsions (HIPEs) of limonene and ethylene glycol dimethacrylate (EGDMA). The bio-derived monomer content in the total monomer composition was set to 50 vol%. To vary the openness and permeability of the resulting porous copolymers, synthesized poly(limonene-co-EGDMA) (PLE-x) copolymers were processed via two different approaches as extraction (E) and lyophilization (L). Ultimately, the ring-porous PLE-E or PLE-L copolymers with different degrees of permeability were used as supporting matrices for the development of form-stable palmitic acid@poly(limonene-co-EGDMA) (PA@PLE-E and PA@PLE-L) composite phase change materials (PCMs). The chemical structure, pore morphology, specific surface area, and thermal properties of the PLE based supports and PA@PLE-E / PA@PLE-L composite PCMs were explored. BET specific surface areas of the ring-porous PLE-E and PLE-L frameworks were measured to be 20.5 m2.g−1 and 4.8 m2.g−1. In addition to that, the latent heats of the resulting composite PCMs were found to be 77.4 J.g−1 and 64.1 J.g−1, while the peak melting temperatures were 63.4 °C and 60.7 °C, for PA@PLE-E and PA@PLE-L, respectively. The bio-derived matrices based thermally stable leak-proof PA@PLE-x composite PCMs with proper latent heat storage (LHS) characteristics are ideal candidates as energy materials for passive solar heating applications due to their favorable phase change temperatures. [Display omitted] •Limonene was used as bio-derived building block for copolymer synthesis.•Porous polymer supports was synthesized by free radical copolymerization of w/o type HIPE of limonene and EGDMA.•Porous copolymers were used as supporting matrices to develop form-stable palmitic acid/poly(limonene-co-EGDMA) PCMs.•The resulting leak-proof composite PCMs were shown to be good candidates for solar energy based LHS applications.