ASTM D3418 - MELTING POINT BY DSC TESTING SERVICES
ASTM D3418 is a method of measuring transition temperatures by Differential Scanning Calorimetry (DSC).Request a quote
Purpose:Measures the temperature and energy of thermal transitions such as melting point, glass transition, and curing reactions.
Sample:One gram but each individual run uses 5 to 20 milligrams.
Price & Delivery: Contact us for a quote.
Basic Description:A Differential Scanning Calorimeter (DSC) is basically two miniature hot plates which hold saucer-shaped pans. One of the pans is filled with sample and the other is kept empty as a control. Both pans are heated at the same temperature ramp rate and the energy required to keep each one heating is continuously measured. The pan filled with sample will require extra energy to heat through a transition such as a melting point because extra energy is required to change the molecule from a solid to a molten state. This difference in energy is recorded as a peak on the DSC scan which indicates the temperature and energy of the transition. The signal from the DSC is usually plotted with temperature on the X-axis and heat energy on the Y-axis. Melting or boiling points look like a downward (endothermic) peak since they absorb energy, glass transitions look like a stair step, and most curing reactions show an upward (exothermic) peak.
Limitations:Weak glass transitions such as in polyethylene and polypropylene are usually not strong enough to detect. Phenolic materials typically give off water as a by product of curing which boils and shows a downward (endothermic) peak in the same range as the curing (exothermic) peak so they cancel each other out. Limited to a temperature range of -90°C to 550°C.
Method Publisher: www.astm.org