Sorption and diffusion of gold and silver nanoparticles in solution through nitrile rubber membrane

Mechanical and physical properties of the rubber material may be affected by swelling when brought into contact with solutions of engineered nanoparticles (ENP). As the rubber swells in the liquid carrier of the ENP, the polymeric chains of the network expand and the ENP can penetrate the structure being carried by the diffusion of the liquid. The aim of this work is to assess the influence of ENP and evaluate the effect of additives present in the solutions on the diffusion process through a rubbery structure. Swelling of membrane material specimens was evaluated by measuring mass gain and liquid diffusion was then deduced. The present study focuses on the contact of nitrile rubber membranes with commercial gold ENP (5 and 50 nm in diameter) and silver ENP (50 nm) in MilliQ water. Swelling tests were also conducted with MilliQ water and filtrates (the solutions from which the ENP were extracted). Results show that the diffusion coefficients of all the solutions of ENP are slightly different and are around 1.2 x 10(-10) cm(2)s(-1). However, it should be noted that these coefficients are notably higher for the filtrates and reach 2.4 x 10(-10) cm(2)s(-1) for the filtrate of the silver ENP. This result underscores the effect of the ENP on the liquid penetration process. We also found that the ENP has a noticeable effect on the Fickian diffusion mechanism of the penetrant; it was noticed that the presence of these nanoparticles lowers the diffusion mechanism index. Moreover, the size of the nanoparticles was found to have an impact on the diffusion coefficient of the solutions as well as their solubility. These findings help to better understand the diffusion phenomenon of the ENP through nitrile membrane materials. (c) 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45350.