What is a Temperature Rise Set Curve and Why is it Important?

Plaster of Paris is useful because it is easily mixed with water to make a slurry that will set very quickly.  The final properties of the solid depend on many factors, such as the final density, gypsum crystal size and shape and setting properties.  When the plaster or stucco sets, the temperature of the slurry rises as heat is generated in the setting process.  The shape of the temperature rise curve is very useful in determining the properties of the hydration process and the final product. 

Innogyps produces a test kit apparatus and associated software tools that measure temperature rise and analyze the resulting set curve.  The kit consists of a foam calorimeter, thermocouple probe and handheld datalogger with acquisition software and is expandable to run multiple instances at one time on a Windows PC.  An Excel-based data analysis tool is then used to smooth the data and plot a graph of the set curve and the derivative curve with all of the relevant output measurements to one output datasheet.  Output variables include temperature rise, setting time, maximum rate of rise, percent hydration at various input times like the knife or dryer entry and others.  The analysis tool also stores past analysis results for quality control plotting.