## 1 Introduction  
Copper is one of the unique elements in a heavy metal cluster which is classified as biogenic Copper is vital in maintaining human health but only at minimum quantity, while excessive exposure is deadly carcinogenic. According to the World Health Organization (WHO), the permitted limit of Cu in water is 2.0 mg/L [1]. Industries such as fertilizers, motor vehicles, petroleum refineries, aircraft plating, steelwork foundries, and pulp and paper mills are typical contributors of Cu into the environment [2]. Thus, the removal of Cu from water is most vital. Commercially, numerous chemical and physical technological solutions are available for the removal of heavy metals such as Cu from water. Synthetic and natural material-based adsorbents onto the removal of toxic heavy metals had gained some popularity in recent years [3]. Polymeric materials provide good quality of water, reusable, cost-effective, and easy to handle. Thus, polymeric materials own some advantages in comparison to other, which favors them to be used as an adsorbent. Anyhow, polymer requires surface modification to provide good adsorptive properties. One of the recognized techniques available for the polymeric material surface modification is radiation-induced graft polymerization [4]. Glycidyl methacrylate (GMA) was widely used as a precursor monomer, mostly for the surface modification of polymeric materials via the radiation-induced graft polymerization technique. It, as an epoxy group is susceptible to functionalization with various type functional groups [5]. Among all the functionalization precursor agents, amine had imposed strong chelating properties towards transition metals. Previously, numerous studies that applied substrates such as cellulose [6], polystyrene [7], polyethylene non-woven fabrics [4], polyglycidyl methacrylate (PGMA) [8], and composite materials [9]. These materials had been functionalized with various amines to prepare an adsorbent for the application of recovering heavy metal ions from aqueous solution [10; 11; 12]. Surface functionalization of polymer materials with PGMA was preferred in most of the studies, as PGMA exhibits unique properties. Since PGMA has the reactive epoxy group which can be easily modified by various functional groups, it could be introduced good mechanical strength, high acid-base resistance [5; 8; 13]. Amines such as introducing with EDA, DETA, and TETA has used to functionalize PGMA-based materials for the metal ions adsorption [14; 15]. Numerous studies had been conducted to identify the relationship between the efficiency of metal ions removal with a molecular chain length of amines. Studies had explicitly been carried out to investigate the role of an amine with a longer molecular chain and amine group density on metal ion adsorption capacity [4; 8]. adsorbent incorporated with selective properties possesses a significant advantage over adsorption of targeted metal ion individually. Adsorbents with a nitrogen-based functional group are very effective in the removal of heavy metal ions [16]. Several techniques employed to associate selective removal characteristics onto adsorbent [8; 17]. On top that, despite many studies reported on metal ion adsorption capacity varies on numerous amines, nothing was emphasized on the selectivity of metals ions based on the molecular chain length of amines. Thus, this study focused on the selectivity of metal ions by adsorbents functionalized with different aliphatic amines. In this study, selectivity characteristics were incorporated onto amine immobilized GMA-based polymer adsorbent via radiation crosslinking technique to form a cavity that is complementary to the targeted ion. The polymer adsorbent which denotes hereafter as ion recognition polymer (IRP) works based on preorganized functional monomer interaction with imprinted template ion via ascertaining chemical interface among them by the aid of the crosslinking process after that [18].