Popis: |
Given their excellent properties, such as high thermal and environmental stability, good conductivity, ease of synthesis, and ability to modify many other properties, conductive polymers are increasingly being studied in both industrial applications and academic research [1]. Poly(3, 4- ethylenedioxythiophene) is one of the most studied conductive polymers due to its remarkable stability, tunable conductivity, easy synthesis by oxidative polymerization or electrochemical synthesis, and wide range of applications [2]. In exploring new materials for use as wearable electronics and electronic skin, PEDOT is a great research option. The lack of mechanical properties such as stretchability and self-healing properties are limiting factors for this purpose, but fortunately polymers can be optimized in many ways. One of the best controlled tools for this is atom transfer radical polymerization (ATRP), which is used in this research to control the molecular weight, chain length, and thus properties of the final products [3]. PEDOT itself is not suitable for such polymerization, so the first thing required is the synthesis of modified PEDOT. This can be easily done by oxidative copolymerization of 3, 4- ethylenedioxythiophene (EDOT) monomer and 2- (thiophen-3-yl)ethyl 2-bromo-2-methylpropanoate (ThBr) monomer.ThBr has the same thiophene group as EDOT but is functionalized with α- bromoisobutyryl bromide (BiBB) to be suitable for ATRP synthesis, which takes place at the alkyl halide group [4]. Finally, poly(ethylene glycol) methacrylate (PEGMA) is used as ATRP monomer to improve the desired mechanical properties. Branches of PEGMA are grafted onto the ThBr part of the polymers (Figure 1) to increase the stretchability and achieve self-healing properties through hydrogen bonding. In this research, the conditions of ATRP synthesis are investigated, such as different reaction times and different temperatures. All synthesized products are characterized by different techniques such as NMR, FTIR, GPC, TGA and DSC. Mechanical properties, conductivity and selfhealing are also investigated. |