raw · papers · ingested 2026-07-02
Stabilizing salt-hydrate PCMs — nucleators & thickeners (borax, sodium polyacrylate)
confidence: high
Source: https://www.nso-journal.org/articles/nso/full_html/2024/03/NSO20230056/NSO20230056.html
Source: NSO / Nano Select review 2024 (NSO20230056). Peer-reviewed; open-access HTML (WebFetch-blocked, data from extract). Credibility: High — additive names with wt% and °C numbers.
Key points
- Supercooling → nucleator: borax at 4 wt% cuts CaCl₂·6H₂O supercooling 14 °C → 4 °C; SrCl₂·6H₂O → ~2 °C; borax can approach 0 °C.
- Phase segregation → thickener: anhydrous salt settles each cycle, killing capacity; sodium polyacrylate gel (or other polymer gel) holds it homogeneous.
- Standard three-additive recipe: KCl (melt-point adjust) + borax (nucleator) + sodium polyacrylate (thickener).
- Corrosion: salt hydrates attack metals → use plastic/glass containment, no metal fins.