(2013) Well-defined poly(N-isopropylacrylamide) with a bifunctional end-group: synthesis, characterization, and thermoresponsive properties, Designed Monomers and Polymers, 16:5, 465-474, DOI: 10.1080/15685551.2012 In this study, well-defined poly(N-isopropylacrylamide) (PNIPAM) with a bisalkyne end-group was synthesized by reversible addition-fragmentation chain transfer polymerization using 2-(2-(ethylthiocarbonothioylthio)-2-methylpropanoyl-oxy)ethyl 3,5-bis(prop-2-ynyloxy) benzoate (EMEB) as the chain transfer agent. The molecular weight and polydispersity index of polymer was determined by gel permeation chromatography (GPC). The linear increase in molecular weight with conversion, unimodal, and almost symmetrical peak in GPC trace together with low polydispersity indicated the controlled polymerization process of NIPAM mediated by EMEB. Subsequently, the Cu(I)-catalyzed [3 + 2] Huisgen cycloaddition between the end-group of polymer and azide derivatives was carried out to produce PNIPAM, in which the bisfunctional end-group was modified with phenyl, octyl, amido, and hydroxyl groups. After completing the click reaction, the structure of the polymer was characterized carefully by Fourier transform infrared spectroscopy (FTIR), 1 H NMR, and Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS), indicating the complete consumption of alkyne end-groups. In addition, almost no change in molecular weight as well as the polydispersity was observed by comparison with the GPC traces of polymers before and after click reaction. The cloud point temperatures (T cp s) of the resulting PNIPAM derivatives in aqueous solution were investigated in detail by dynamic light scattering. The results showed that the values of T cp were ranged from 22 to 38°C, which depended largely on end-groups as well as the polymer molecular weights.

Nitrogen-doped porous carbon materials have now become one of the most important candidates for efficient oxygen reduction electrocatalysis and supercapacitors because of their low cost and high stability. In the present study, a novel triazine-based, quaternary bipyridinium-type framework (TBPF) is synthesized by polycondensation of 4,4'-bipyridine with cyanuric chloride. The as-synthesized TBPF is then subject to pyrolysis at 900°C, yielding N-doped porous carbon (N/C-900). The N/C-900 material possesses brain-like architecture, high Ncontaining functionalities (5.40 at.% N), and relatively high specific surface area (684 m 2 g À 1 ), which can act as a truly metal-free catalyst toward ORR and an electrode material for supercapacitors. Due to the synergistic effects, the N/C-900 material shows outstanding ORR electrocatalytic activity and stability in alkaline media with an onset potential of 0.969 V (vs RHE), a half-wave potential of 0.843 V (vs RHE), a limited current density of 5.05 mA cm À 2 , and a 3 mV negative shift of half-wave potential after 3000 cycles. Furthermore, the N/C-900-based supercapacitor electrode also displays relatively high specific capacitance (217 F g À 1 at 0.5 A g À 1 ) and excellent stability (96 % capacitance retention after 10000 cycles) in 6 M KOH electrolyte. and acetone. After drying to a constant mass, a dark green powder was obtained with a yield of 91 %.

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