## 1 Introduction  
In recent years, the development of industrialization and urbanization has aroused global attention to environmental pollution. Organic pollutants in most developing countries have no effective treatment and are directly discharged into the environment during the production process, including the petroleum, chemical, pharmaceutical, textile, and plastics industries. Health and environmental issues have stemmed from them because of their high toxicity and difficult degradation [1; 2]. Anilines are applied as intermediates in the production of pesticides, drugs, dyes, rubber, and herbicides [3; 4]. Anilines are one kind of significant organic pollutants in our environment, and the discharge of these contaminants may cause great harm to the environment and the drinking water even when they exist as a trace [5]. For example, the US Environmental Protection Agency (EPA) suggests that the maximum acceptable concentration of aniline in water is 0.262 ppm [6]. For the sustainable development of the water environment, it is of significance to develop efficient ways for the removal of toxic organic substances in wastewaters. Various treatment methods such as biodegradation, photocatalytic degradation, ozonation oxidation, and adsorption have been employed to eliminate anilines from wastewaters [7; 8; 9]. Among these methods, adsorption is one of the most effective approaches to remove these pollutants because it has certain advantages, such as low cost, simplicity, and effectiveness. A hyper-crosslinked polymer (HCP) is an efficient adsorbent for the removal of anilines because of specific surface areas, porous structures, and surface physicochemical characteristics [10; 11; 12]. The Friedel-Crafts reaction has been used to synthesize HCPs by using low crosslinked chloromethylated polystyrene (CM-PS) as a starting skeleton in the presence of Lewis acids in solution. A previous publication has shown that the as-synthesized HCP shows low equilibrium capacity for the polar compounds due to hydrophobic surface [13]. Chemical modification has been considered to introduce different functional groups such as -OH, -NH\({}_{2}\), and -COOH into the polymers, which can increase the adsorption capacity for poisonous organic chemicals. Therefore, HCPs modified with polar components have been studied during the past decades [11; 12; 14; 15]. Cyclodext (CDs), which include 6-8 \(\alpha\)-(1-4)-linked \(\alpha\)-D-glucopyranose units to form a hydrophobic center and hydrophilic edge, are a class of natural cyclic oligosaccharides derived from starch (named \(\alpha\)-, \(\beta\)-, and \(\gamma\)-CD, respectively) [16; 17]. CDs can form inclusion complexes via the weak interactions with aromatic compounds in aqueous solutions [18; 19]. \(\beta\)-CD is one of the cheapest and most extensively used CDs, and it is conducive to the removal of polar aromatic compounds from wastewaters through the host-guest interactions between adsorbent and adsorbate. However, there is an obvious deficiency in the application of \(\beta\)-CD due to its solubility, and immobilization on certain supports to realize its recyclability is an ideal method. \(\beta\)-CD-based materials have been applied in removing organic pollutants such as aromatics or phenolics from the environment [20; 21]. [PERSON] et al. [22] constructed a hyper-crosslinked \(\beta\)-CD porous polymer by crosslinking benzylated \(\beta\)-CD with dichloroxylene via a Friedel-Crafts reaction, which has a high surface area and good thermal stability with an adsorption capacity of 278 mg/g for bisphenol A at 25 \({}^{\circ}\)C. [PERSON] et al. [23] also synthesized a \(\beta\)-CD-based HCP by reacting benzylated \(\beta\)-CD with formaldehyde dimethyl acetal, and an exceptional adsorption performance was observed for the removal of aromatic compounds in aqueous solutions. However, their industrial applications have been limited by the complex preparation process and the use of large organic solvents.