Understanding the Host-Guest Interaction Between Responsive Core-Crosslinked Hybrid Nanoparticles of Hyperbranched Poly(ether amine) and Dyes: The Selective Adsorption and Smart Separation of Dyes in Water

The hostguest interaction between polymer nanoparticles and guest molecules plays a key role in fields such as controlled drug delivery, separation, and nanosensors. To understand this hostguest interaction, a series of hybrid polymer nanoparticles (SiO1.5-hPEA NPs) are designed and prepared based on hyperbranched poly(ether amine) (hPEA) with the different hydrophobicity and functional groups. Their adsorption behavior to twelve hydrophilic dyes in aqueous solution is studied. The core-crosslinked hybrid nanoparticles (SiO1.5-hPEA NPs) are prepared by direct dispersion of hPEA containing trimethoxysilyl moieties (TMS-hPEA) in aqueous solution, which exhibit sharp multiresponse to temperature, pH, and ionic strength in aqueous solution. The effect of molecular structure of TMS-hPEA on the hostguest interaction between SiO1.5-hPEA NPs and hydrophilic dyes is investigated in detail. The obtained SiO1.5-hPEA NPs interact selectively with different hydrophilic dyes in aqueous solution. The distribution coefficient (K) for partitioning of dyes between SiO1.5-hPEA NPs and water is proposed to define the strength of the host-guest interaction between the nanoparticles and dyes. K increases with the increasing hydrophobicity of the hPEA backbone regardless of their charge states of SiO1.5-hPEA NPs and dyes. A methodology is demonstrated for the smart separation of a mixture of dyes in water using SiO1.5-hPEA NPs.