Atmospheric gas-particle partitioning of E-EHMC and Z-EHMC estimated from their liquid vapour pressures at 298.15 K

Abstract

The UVB filter E-ethylhexyl p-methoxycinnamate (E-EHMC) is extensively used as a UV protectant in commercial products. Its photoisomerisation into Z-EHMC is well known. In this work, we estimate the thermodynamic properties of the vaporisation processes of E-EHMC and Z-EHMC using an indirect experimental method developed in our laboratory named Effusion Method under Atmospheric Pressure (EMAP). The atmospheric particle bound fractions and air-particulate partition coefficients for E-EHMC and Z-EHMC were derived from the vapour pressure P/Pa (298.15 K) estimated by EMAP methodology.