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A simple route to size-tunable nanoparticles from the self-assembly of degradable and electrically conductive coil–rod–coil triblock copolymers based on an aliphatic polyester and conducting species is presented. A series of coil–rod–coil triblock copolymers consisting of a middle aniline pentamer (AP) segment and two polycaprolactone (PCL) segments were easily synthesized by a combination of a ring-opening polymerization of CL initiated by an aniline dimer (AD) giving AD-PCL and an oxidative coupling reaction between the AD-PCL and p-phenylenediamine. This strategy avoids the multistep reaction used in previous work. The electroactivity of these copolymers was investigated by UV and cyclic voltammetry. The conductivity of the copolymers was dependent on the AP content and the conductivity mechanism of the triblock copolymers is discussed. Interestingly, these triblock copolymers can undergo self-assembly in selective solvent such as CHCl3as indicated by NMR and transmission electron microscope (TEM) observations. Dynamic light scattering (DLS) showed that the size of the nanoparticles was dependent on the molecular weight of the copolymers and on the oxidation state of the AP. The morphology of the nanoparticles was studied by TEM and SEM. These triblock copolymers and their size-tunable nanoparticles with degradability and electroactivity offer new possibilities in biomedical applications, such as controlled drug delivery, biosensors, and cardiovascular and neural tissue engineering. [ABSTRACT FROM AUTHOR]

Degradable electrically conducting hydrogels (DECHs), which combine the unique properties of degradable polymers and electrically conducting hydrogels, were synthesized by introducing biodegradable segments into conductive hydrogels. These DECHs were obtained by joining together the photopolymerized macromer acrylated poly(d,l-lactide)−poly(ethylene glycol)−poly(d,l-lactide) (AC-PLA-PEG-PLA-AC), glycidyl methacrylate (GMA), ethylene glycol dimethacrylate (EGDMA) network and aniline tetramer (AT) by the coupling reaction between AT and the GMA. The electrical conductivity and swelling behavior of these DECHs were tuned by changing the AT content in the hydrogels, the cross-linking degree, and the environmental pH value. The good electroactivity and thermal stability of these hydrogels were demonstrated by UV−vis spectroscopy, cyclic voltammetry, and TGA tests. The chemical structure and morphology of these polymers were characterized by NMR, FT-IR, SEC, and SEM. These hydrogels possessing both degradability and electrical conductivity represent a new class of biomaterial and will lead to various new possibilities in biomedical applications. [ABSTRACT FROM AUTHOR]