Modeling the adsorption mechanism of 3-tertiary-butyl-4-hydroxyanisole (3BHA) on polyethylene and polypropylene microplastics

Abstract

The Polyethylene (PE) and polypropylene (PP) microplastics (MPs), can act as carriers of the molecule 3tertiary-butyl-4-hydroxyanisole (3BHA), which propose harmful impacts to aqueous ecosystems. Meanwhile, 3BHA has already been detected in several environments and human urine and serum samples. 3BHA is an antioxidant in foods, food packaging, cosmetics and pharmaceuticals. However, it raised concerns about its possible endocrine-disrupting effect in recent years. The interaction between two MPs and 3BHA could start in farmland and be maintained during transportation to the ocean. Herein, the adsorption behavior and mechanism of 3BHA by PE and PP MPs were investigated via molecular dynamics (MD) simulation, density functional theory (DFT), non-covalent interactions (NCI), the density of states (DOS) and frontier molecular orbital (FMO). Furthermore, the stability of 3BHA adsorbed complexes was investigated by adsorption-free energies (ΔGads), showing that the 3BHA has a signi cant interaction with the MPs studied, mainly with PP MP. Intermolecular van der Waals forces were one of the primary adsorption mechanisms of 3BHA by MPs, as evidenced by NCI calculations. It was demonstrated that the adsorption of the 3BHA in MPs decreases the energy gap of the HOMO and LUMO orbitals, as well as a slight shift in the HOMO and LUMO states in the TDOS analysis. In conclusion, this study about the mechanism of adsorption of the 3BHA in PE and PP MPs can provide new evidence and enhance our understanding of the environmental behavior of 3BHA in the environment.

1,3,5‐Benzene Tricarboxylic Acid Based Cocrystals With Selective Semiconductivity via H‐coupled Charge Transfer

“…The visual look of NCI plot is given in the Figure 12 which we made using VMD software. [59] From Figure 12 we can see that the amino-pyridine complex has stronger H-bond like interaction (blue in colour) is present in crystal structure geometry as compared to apparently weak Hbonding (blue in colour) interaction for the optimized geometry. However, in urea complex the crystal structure as well as optimized structure has no such H-bond like interaction (green in color).…”

“…SCXRD data, on the other hand, the structure of cocrystal 2 which is a high Z' structure [59] with the value of Z' = 8 shows the presence of 2 : 1 : 1 molecular ratio of TMA, urea and methanol respectively in the structure of cocrystal 2 (Figure 2a). The TMA and urea moieties in this cocrystal form intermolecular H-bonds involving the sets of atoms O4AÀ H2NBÀ N2A, O4AÀ H1NBÀ N1A, N2AÀ H2NAÀ O5C, O7AÀ H6OCÀ O6C, O2BÀ H2OBÀ O7B, O1BÀ H2NCÀ N2B, O4CÀ H4OCÀ O7B, O3CÀ H1NCÀ N1B whereas the sets of atoms O6AÀ H4OBÀ O4B, O5AÀ H5OAÀ O3B, O1CÀ H1ODÀ O1D, O2CÀ H2OCÀ O2D are also found to be associated in the intermolecular H-bonding between two TMA moieties of the same structure.…”