Study On Intelligent Microgel Based On Hyperbranched Poly(ether Amine) And Its Application For Smart Separation

With the rapid development of those industries based on chemicalengineering and technology, the increasing amount of industrial waste waterbecomes a serious problem. Either the treatment of tens of billions of tons ofwaste water or the preparation of the drinking water from raw water has poiseda higher demand for the technologies for treatment of water. More studies onintelligent materials illustrate that, with the recognition properties of theintelligent materials, it can not only remove the pollutants, but also condenseand separate some special substances which can be further reused.Among those intelligent materials, most focus on the stimuli-responsivematerials which, according to the origin of the response, can be classified intoseveral categories: photosensitive materials, pH-responsive materials,temperature-responsive materials, multi-responsive materials, and etc. As akind of host material, such materials can interact with some guest moleculesthrough such interactions as hydrogen bonding, electrostatic interaction, π–πstack or polarity interaction, and as a result, such high-performance materialscan be used for some special areas, such as catalysis, targeted release, smartseparation, chemical and biological sensing, molecular switching, etc. Based onthe studies on stimuli-responsive materials and previous work on the novelpoly (ether amine) developed by our group, in this work, we manufactured akind of monodisperse intelligent microgel (Diameter=250nm, PDI=0.15)with hydrophobic core and hydrophilic shell through the co-assembly of doublebond-ended hyperbranched poly(ether amine) and pentaerythritoltetra(3-mercaptopropionate)(PTMP) in aqueous solution, followed by thiol–ene photo-click crosslinking. The obtained microgel exhibits sharpresponse to pH, temperature and ionic strength.The interaction between the host hPEA-mGel and a series of fluoresceindyes, which is defined quantitatively by distribution coefficient K, wasinvestigated. hPEA-mGel exhibited strong adsorption to ETB, RB, EB, DBFand TCF with relative high K, but very low affinity to FR and Cal with relativelow K. The big difference in the interaction between hPEA-mGel and differentfluorescein dyes is indicative of the selective adsorption of hPEA-mGel tofluorescein dyes, which resulted from hydrophobic not electrostatic interactions.Based on the selective adsorption of fluorescein dyes by hPEA-mGel, wedemonstrated a simple approach to separate a mixture of fluorescein dyes inaqueous solution.