Meaning
Hermetically sealed sample containers designed to withstand the elevated internal pressures generated by volatile emissions or rapid gas generation during heating define this laboratory hardware. In thermal analysis, a high pressure crucible prevents the vaporization of solvents or water from masking other thermal events like curing or melting. This container ensures that the sample remains under a self-generated pressure atmosphere during the entire analysis run.
Such confinement is necessary for studying reactions that occur in aqueous or organic solutions where evaporation would otherwise distort the heat flow signal.
Material Selection
Stainless steel or gold-plated alloys are typically used to manufacture these robust sample cells to prevent chemical attack and leakage. When using a high pressure crucible, the seal must withstand pressures up to several megapascals without deformation. This structural rigidity prevents the release of volatile components, allowing the instrument to measure true reaction kinetics.
Testing Application
Differential scanning calorimetry utilizes these specialized cells to study hazardous reactions and energetic materials. Using a high pressure crucible keeps volatile reactants in the liquid phase where they can continue to react at temperatures above their normal boiling points. This capability is essential for simulating the high-pressure conditions of industrial chemical reactors.
Safety Function
Sealed analysis runs protect sensitive laboratory instrumentation from contamination and corrosive fumes. A high pressure crucible isolates the sample from the cell holder of the calorimeter, preventing damage to delicate heat flux sensors. This isolation reduces instrument downtime and ensures the repeatability of baseline calibrations.
