Application of an all-polymer flexural plate wave sensor to polymer/solvent material characterization

VOC detection using an all polymer flexural plate wave sensor

“…The results are then compared to a semi-empirical performance model, created to describe frequency shift as a function of the properties of the polymer sensing layer. This model is similar to that described in [1], however, it relies on Flory-Huggins solution theory to predict polymer mechanical properties, rather than the partition coefficient and empirical data.…”

“…For this model, we use a previously reported Young's Modulus for the elasticity of the dry film, E 0 , from [8] and [9]. In order to verify the validity of the sensing layer properties predictions, the calculated thickness, density and Young's modulus of a PVA film exposed to water vapor were compared with experimental data from [1].…”

“…Full details of this process can be found in [1] and [3]. Key characteristics of the sensor used here are described in table 1.…”

“…As detailed in [1], the wave velocity and frequency of the fundamental, antisymmetric mode of propagation for a flexural plate wave can be approximated using Kirchoff's plate equation for thin plates In a previous model, these variables were obtained from experimentation and literature [1,2]. Due to the lack of complete experimental mechanical data available on PVAc and PS in the presence of toluene vapor, mass density, thickness and Young's modulus are described using Flory-Huggins (FH) solution theory.…”

“…PDVF flexural plate wave acoustic sensors have shown promise as inexpensive chemical detectors [1][2][3]. Due to the low stiffness of the substrate, these devices can measure analyte induced density, thickness, stress and elasticity changes in a polymer sensing layer.…”