c. 1948
Telkes Dover house
Maria Telkes’ Glauber’s-salt solar house — leaks and layering taught humility.
Phase-change material did not arrive as a finished commodity. NASA / Telkes 1940s–70s; building PCM 2000s around United States / Germany still explains who makes it and which tests it sits in.
Ten dated points, five eras and three milestones below are the spine — not a complete industrial history.
Where it began
NASA / Telkes 1940s–70s; building PCM 2000sUnited States / Germany
Timeline
c. 1948Telkes Dover house
Maria Telkes’ Glauber’s-salt solar house — leaks and layering taught humility.
1960sNASA PCM
Spacesuit and electronics thermal capacitors.
1970sSalt-hydrate R&D
Supercooling and phase separation as the plot.
1990sMicroencapsulated paraffin
BASF Micronal in plaster.
2000sPCM gypsum boards
Comfort claims in lightweight buildings.
2010sEN / ASTM test methods
h(T) curves instead of brochure magic.
2010sCold-chain packs
The market that actually ships.
2010sGraphite composite PCM
Conductivity additives.
2020sBattery packs
Passive buffering between cells.
2020sBio-based waxes
Still combustible.
The eras
1970s
Salt-hydrate R&D
Supercooling and phase separation as the plot.
2000s
PCM gypsum boards
Comfort claims in lightweight buildings.
2010s
Cold-chain packs
The market that actually ships.
2020s
Battery packs
Passive buffering between cells.
Milestones
Microencapsulated paraffin
1990sBASF Micronal in plaster.
Cold-chain packs
2010sThe market that actually ships.
Bio-based waxes
2020sStill combustible.
Knowing this timeline is how to read a mill certificate without treating Phase-change material as timeless.
Keep exploring
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Overall 44