One-Step Bulk-Suspension Polymerization of Polyethylene Glycol-Based Copolymer Microspheres for Phase Change Textiles

Abstract

The paper presents a feasible strategy through one-step bulk-suspension polymerization, grafting PEG onto an in situ synthesized copolymer. In more detail, PEG was grafted onto a homemade polystyrene/maleic anhydride copolymer (SMA) via bulk-suspension polymerization with poly(vinyl alcohol) as a suspending agent. According to the optimal reaction conditions, the grafting rate of PEG was 56.2% through chemical titration experiments. At the same time, the quantitative relationship between the grafting rate and enthalpy was demonstrated for the first time in a PEG-based solid–solid phase change material (S-SPCM). Morphology observation revealed that the obtained S-SPCM is made up of white microspheres of approximately 100–150 μm. The powdery product polystyrene/maleic anhydride grafted polyethylene glycol (SMA-g-PEG) obtained through bulk-suspension polymerization endowed that the whole product could be used directly as a phase change material without postprocessing. The melting enthalpy and crystallization enthalpy of SMA-g-PEG were 79.3 J/g and 76.9 J/g, respectively. Based on the effective fixed load of PEG, the macrostructure of SMA-g-PEG was almost unchanged at 70 °C compared with the macrostructures at 20 °C, and the latent heat of SMA-g-PEG was decreased slightly after 1000 thermal cycles. Overall, the obtained SMA-g-PEG can be used as a filler in insulation materials and composited with fibers to obtain phase change thermoregulated smart textiles.

Effect of the Preparation Methodology of Polydopamine-Containing Systems over Light-to-Thermal Energy Conversion Performance

“…Thus, the actual enthalpies of PEG in the composite system may be lower than theoretical enthalpies . Although, with the best knowledge, there is no similar material system in the literature, the latent heat-storage performance of the prepared composite system is comparable with the studies having close material combination. ,,,− The melting and solidifying temperatures of the composite samples were also evaluated separately because the phase-transition temperatures are critical issues for using phase-change materials in real-life applications. In Figure C, the melting transition of the composite samples was found at lower temperatures, probably due to the confinement of PEG within the PS@PDA matrix induced by surface intermolecular interactions such as hydrogen bonding .…”