Methyl acrylate functionalized hyper-crosslinked polymers and their efficient adsorptive removal of aromatic small molecule compounds from water

Herein, methyl acrylate functionalized hyper-crosslinked polymers (HSDMs) were synthesized using the suspension polymerization method and they were employed to adsorb aromatic small molecule compounds. Low-crosslinked precursor polymers were prepared using styrene (St) and divinylbenzene (DVB) as crosslinking agents and different ratios of methyl acrylate (MA, 20, 15, 10, 5%) as functional monomers. Subsequently, the Friedel–Crafts reaction was conducted at 313 K to yield products characterized by hyper-crosslinked interpenetrating polymer networks abundant in rigid methylene bridges. The resulting polymers were promising for the adsorption of aromatic small molecule compounds from aqueous solutions, and the maximum capacities (q_max) for aniline, phenol and salicylic acid arrived at 103.79, 98.75 and 229.98 mg/g at 288 K. The kinetic experiments demonstrated that adsorption aniline, phenol and SA reached the equilibrium within 60, 60 and 150 min, and the kinetic results were accurately described by the pseudo-second-order (PSO) rate model, exhibiting kinetic rates of 8.34 × 10^–4, 1.01 × 10^–3, and 5.00 × 10^–4 g/(mg·min), respectively. At room temperature, the dynamic adsorption capacity of HSDM-5 for aniline is 50.06 mg/g and the desorption efficiency is 90.74%. The adsorption mechanism discovered that hydrophobic interaction, π-π stacking, pore-filling and hydrogen bonding were important for the adsorption. 

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