raw · papers · ingested 2026-07-02
Effect of thermal cycling on thermal & chemical stability of paraffin PCM composites (700 cycles)
confidence: high
Source: https://pmc.ncbi.nlm.nih.gov/articles/PMC11835934/
Source: Open access, PMC11835934. Peer-reviewed primary experiment. Credibility: High.
Key points
- Pure paraffin, 700 cycles: solidification-side latent-heat loss 5% (RT22HC) → 23% (RT25HC); melting-side ~4%. Favor RT22-type for stability.
- Leakage is the dominant failure: encapsulated samples lost up to 57% via PCM leaking through the coating — not chemical breakdown.
- No chemical degradation: FT-IR unchanged after 700 cycles; no yellowing in a sealed sample → yellowing is a UV/O₂-ingress problem, so seal out air + block UV.
- Design takeaway: containment integrity and a good seal matter more than the wax grade.