The synthesis, characterization, and functional properties of two new polymerizable 1,8-naphthalimides (MDs) have been described. Their copolymers with styrene designed to act as a fluorescence PET chemosensor have been investigated. The study also reports the influence of different metal cations (Ag+, Mg2+, Cu2+, Sr2+, Co2+, Pb2+, and Fe3+) on the fluorescence intensity of both low and high molecular weight fluorophores. 1. Introduction In the recent years the development of molecular recognition and sensing systems for different analytes has received considerable attention. Fluorescent chemosensors utilised for detection of metal cations and protons in the environment were based on different molecular structures [1, 2]. The fluorescent polymers are very attractive for this purpose. In this case the fluorescent sensor units can be covalently bonded to the polymer chain, thus showing very similar effect to their monomeric sensor units [3]. The functional characteristics of polymer chemosensors can be expressed either by conformational changes of macromolecules or by the collective transport properties. Recently, new polymerizable 1,8-naphthalimide molecules to sensitive protons or metal cations have been synthesized and their functional properties are investigated. Due to the presence of a polymerizable group they can react with some commercial monomers, allowing copolymers with a green or blue fluorescence to be obtained. It was demonstrated that the copolymers of these polymerizable sensors can be used as homogeneous and heterogeneous photoinduced electron transfer (PET) fluorescent sensors sensitive to metal cations [4–9]. In all cases 1,8-naphthalimides are enough thermo- and water resistible so the polymers can be used for ion determination in solution without contaminating it. The scientific tasks on development of polymeric systems for detection of environment pollutants will be focused on finding such polymeric systems which have specific chemical, physical, and mechanical properties as transparency, resistance to different environment factor and the harmful chemical substances, flexibility, and so forth. In this paper we present the synthesis and functional properties of two new polymerizable 1,8-naphthalimides (MDs) and their copolymer with styrene designed to act as fluorescence chemosensors. The influence of different metal cations on the fluorescence intensity of both low and high molecular weight sensors has been investigated and discussed. 2. Experimental Part 2.1. Materials and Methods 4-Amino-N-allyl-1,8-naphthalimide was synthesized
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