Building Materials
To retard the initial setting time of cement, the compound responsible, is

Tri-calcium aluminate
Gypsum
Di-calcium silicate
Tri-calcium silicate

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Building Materials
The thermosetting plastic

Chars at 343°C
At 127°C to 177°C permanently set and further application of heat does not soften it
Becomes rigid when moulded at suitable pressure and temperature
All listed here

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