Model of absorption of gaseous naphthalene by ordered layers of polymer submicroparticles with nanostructured shells

Abstract

A new model describing the kinetics of absorption of naphthalene vapor from the atmosphere in three-ordered layers of polymer submicroparticles (400–450 nm) with both simple and porous (modified) shells and an impenetrable core was proposed. The experiment examined the layers of polymer particles made of poly(ethylene glycol dimethacrylata) (PEGDM) containing various amounts of monolayers (2, 5, 10, and 20). The processing of the experiment using a physical model allowed one to obtain the rate constants of the naphthalene absorption by the polymer and the template pores of the particle shell. Based on these results, the effective thickness of the particle shell (about 15 nm) was estimated; the effective diffusion coefficient of the naphthalene in the polymer is D ≈ 0.2 nm2 s−1. The effective value of the energy barrier of the naphthalene sorption by the particle surface (about 4–5 kcal/mol) was calculated, which approximately corresponds to unsaturated hydrogen bond energy and may indicate the role of the adsorption layer of moisture on the particle surface. The efficiency of the model in describing the two-stage absorption of the analyte by the layers of submicroparticles with nanoporous shells was shown.