Abstract While numerous phenoxazine-based small molecules developed for organic electronic devices, very limited attention has been received on synthesized conjugated polymers containing this phenoxazine. Herein, we designed and synthesized two new low-bandgap donor−acceptor conjugated copolymers based on phenoxazine with different side chains and diketopyrrolopyrrole by Pd-catalyzed direct (hetero)arylation polycondensation using a Pd(OAc)2 catalyst and PCy3.HBF4 ligand. The effects of side chain branched alkyl and benzoyl of phenoxazine on the thermal, and optical properties of the polymers have been investigated. Both the polymers have a good yield 85%, high molecular weight up to 41500 g/mol, low dispersity index 1.91, excellent solubility in common organic solvents, and a broad absorption spectrum in the range of 500-900 nm with optical bandgaps as low as 1.40 eV. All these polymers possess good thermal stability with decomposition temperatures over 350 oC and no obvious thermal transitions.

Abstract The synthesis of poly(L-glutamic acid) (PG) was investigated. Reduction of poly(benzyl-L-glutamate) by the palladium/charcoal catalyst proved to be an effective method for obtaining polyglutamic acid pure and particularly exhibiting in the α-helix secondary structure. The structure of this synthetic polypeptide was assessed by infrared spectroscopy, gel permeation chromatography, proton nuclear magnetic resonance spectroscopy, temperature-modulated differential scanning calorimetry and wide-angle powder X-ray diffraction methods. The α-helical PG was, for the first time, combined with multi-walled carbon nanotubes (MWCNTs). The obtained PG was demonstrated to be a promising matrix to disperse MWCNTs, forming MWCNT/PG biocomposites.

Abstract The UV light-mediated metal-free polymerizations of 4-vinylpyridine (4VP) have been successfully performed by using 10-(pyren-1-yl)-10H-phenothiazine (PPTh) and pyrene as photocatalysts. The preparation of narrow polydispersity poly (4-vinyl pyridine) (P4VP) with high conversions was enabled in both protic as well as unprotic reaction media at ambient temperature. Additionally, copolymerizations of 4VP with acrylate and methacrylate monomers were also demonstrated, affording metal-free copolymer products.

Abstract In this research, a novel organic photocatalyst of 10-(Perylene-3-yl-10H-Phenoxazine (PHP) has been synthesized successfully from perylene and phenoxazine via Buchwald-Hartwig C-N coupling. The chemical structure of catalyst was determined via proton nuclear magnetic resonance (1H-NMR) spectrum and optical properties were investigated through UV-Vis spectroscopy. The PHP has been used as the reducing photoredox catalyst for organocatalyzed atom transfer radical polymerization (ATRP) under UV irradiation. The well controlled molecular weight of polymers based on methyl methacrylate monomers have been obtained with monomer conversion up to 77.61% and low polydispersity index under 1.5.

Abstract The photoswitchable poly(methyl methacrylate-random-methacrylate spirooxazine) was synthesized via atom transfer radical polymerization with the feed mole ratio of MMA/MSp comonomer of about 5.5/1. Well-defined poly(methyl methacrylate- random-methacrylate spirooxazine) have been obtained with the average molecular weight (Mn) of 6500 g/mol and polydispersity of 1.21. The structure and properties of the resulting copolymers were characterized by proton nuclear magnetic resonance (1H NMR), gel permeation chromatography, Fourier Transform infrared, UV-visible spectroscopy, and differential scanning calorimetry. Moreover, the copolymer exhibited the erasable and rewritable photoimaging on the solid state film which could to be as potential candidate for optical data storage materials.

AbstractCarbon nanotubes (CNTs) are a promising candidate material for use in lithium batteries due to 1D tubular structure, high electrical, thermal conductivities, and extremely large surface area. In this work, the MWCNTs were purified by dispersion in a mixture of HNO3 and H2SO4acids. The oxidized-MWCNTs were used as conducting addition to prepare a nanocomposites as high performance cathode material for Li-ion batteries (LIBs). The spinel cathode materials of LiMn2O4 (LMO), doped spinel LiNi0.5Mn1.5O4 (LNMO) were synthesized and characterized via X-rays diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical properties of nanocomposites based on LMO/CNTs and LMNO/CNTs were investigated by cyclic voltammetry (CV) as well as electrochemical impedance spectroscopy (EIS). The EIS measurement indicated that the LMO (LNMO)/CNTs nanocomposites showed lower charge transfer resistance (Rct) than that of LMO(LNMO)/ Vulcan carbon materials. In addition, the studied nanocomposites cathodes gave a specific capacity of 145 Ah.kg–1 and 120 Ah.kg–1 for LMO/CNTs (10 wt%) and LNMO/CNTs (10 wt%), respectively, measured at a charge/discharge rate of 0.1C.

Abstract A novel monomer of S-2-mercaptoethyl 2-(thiophen-3-yl)ethanethioate (MTE) were synthesized via esterification reaction between 2-(thiophen-3-yl)acetic and ethane-1,2-dithiol in the presence of dicyclohexyl-carbodiimide (DCC) and N,N’-dimethylpyridin-4-amine (4-DMAP) as catalytic system. The structure of monomer was characterized via MS, 1H-NMR and 13C-NMR spectroscopies. The electrochemical polymerization of MTE monomer was performed in acetonitrile using lithium perchlorate (LiClO4) as electrolyte agent. The obtained polymer film (PMTE) was characterized via cyclic voltammetry and it exhibited the main oxidation peaks centered at +2V.