Measuring water diffusion of polymers
The Water Vapor Transmission Rate (WVTR) is a very important property in relation to flexible electronics, since in these devices corrosion of metals is usually a delimiter of the lifetime of the device. An accurate and fast measurement of the WVTR is required. However, due to the decreased WVTR, the sensitivities of the classic WVTR measurement methods are challenged.
The Water Vapor Transmission Rate (WVTR) of polymers is expressed in g/(cm2day) under standard conditions and assuming the transport of the water is diffusion-limited. Usually polymers have a WVTR in the range of 1-10 g/(cm2day). For flexible electronics, a WVTR lower than 0,1 g/(cm2day) is needed.
• Replacement of the MOCON test for WVTR, which is very slow and time-consuming.
• Investigate if a MEMS device (microelectromechanical system) could be used for measuring water diffusion.
• Design and working principle was developed for a Radio Frequency - MEMS resonator for antennas in a wafer cavity.
• Q-factor (indication of how under-damped a resonator is) depends on ambient pressure.
• A patent application for this device was filed in the Netherlands (no. NL2004419).