An improved method for measuring vapor pressure by DSC with automated pressure control

Vapor pressure measurements are necessary for a wide range of applications in the chemical industry. Traditional methods require 10-30 mi of sample, 6-8 h of operator time, and multiple measurements for high precision data. With a modification to the pressure differential scanning calorimeter cell, use of hermetic-type pans with pin-holed lids, and the addition of a pressure controller, vapor pressure measurements from 5-760 torr can be obtained. These measurements use less than 1 mi of sample, take about 2 h of operator time, and achieve high precision data on a single set of measurements.