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Poly(glycidyl methacrylate) (PGMA) was synthesized by Fe(0)-mediated living radical polymerization followed with post-modification by PhSeZnCl. A series of selenide functionalized PGMAs with different selenium concentrations and molecular weights were obtained. The introduction of selenide groups into PGMA resulted in a polymer with high refractive index. The relationships between the concentration of selenium, degree of polymerization and refractive index were investigated. Results showed that the refractive index of the final polymer could be adjusted by the concentration of selenium and degree of polymerization, which provided a useful way to fabricate polymeric materials with adjustable refractive index. [ABSTRACT FROM AUTHOR]

Herein, p -phenylseleno styrene (p -PhSeSt) and 4-(1,2,2-triphenylvinyl)phenyl acrylate (TPE-a) were copolymerized by photo-induced reversible addition-fragmentation chain transfer (RAFT) polymerization under blue light at room temperature. The selenide moiety in resulting copolymers could be selectively oxidized to selenoxide or selenone groups by H 2 O 2 or NaClO, respectively, which caused the changing of structure and performance of the copolymer. The structure changing of copolymers during the oxidation was characterized by nuclear magnetic resonance and size exclusion chromatography. Properties of the resulting polymers were systematically investigated before and after oxidation, such as thermal performance, glass transition temperature, water contact angles and refractive indices. In addition, due to the change of hydrophilicity and hydrophobicity of the polymers in aqueous solution after oxidation, the detection of Au3+ and nitrobenzene were successfully realized, constructing a versatile and multifunctional fluorescent probe sensor, which provides potential application prospects for the detection of oxidations. [Display omitted] • Selenium-containing polymers with controlled oxidative behavior was synthesized. • Oxidative responsive property was combined with AIE functionality. • Fluorescent probes for the detection of Au3+ and nitroaromatic were constructed. [ABSTRACT FROM AUTHOR]

Selenium-doped phenolic resin spheres (Se-RS) was synthesized by the reaction of 4,4′-selenodiphenol and resorcinol with formaldehyde catalyzing by ammonia. The whole reaction was completed within 5 min under the acceleration of ultra-sonication. Se-RS with controlled Se-content and Se-distribution were prepared in such manner. The obtained Se-RS showed enhanced Pd2+ and Au3+ adsorption capacity in aqueous solution. The adsorbed Au3+ can be further reduced to Au0 at the surface of Se-RS in situ without additional reducing agent. The Se-RS exhibited exceptional extract capacity of gold from e-waste sewage and other aqua even its Au3+ concentration was extremely low. [ABSTRACT FROM AUTHOR]

Abstract A method combined spray-drying process with light-induced reversible addition fragmentation chain transfer (RAFT) polymerization was used to synthesize N -doped carbon spheres (N -CS). Firstly, the common used carbon precursor phenolic resin which called Resol was modified with a chain transfer agent (CTA). Then, the mixed ethanol solution of CTA modified Resol, F127, TEOS, and HCl was used as starting material. After a typical spray-drying process, uniformed and discrete composite spheres in regular size (70 μm) were obtained. The RAFT polymerization of acrylonitrile was initiated under the irradiation of blue LED at the surface of spheres. Through such manner, controlled amount of polyacrylonitrile was introduced onto the surface of carbon sphere. After calcination at 900 °C and etching, the obtained porous N -CS (60 μm) showed controllable total N content up to 10.8 wt%, tunable high surface area up to 1130 m2/g and good CO 2 absorptivity which can up to 4.34 mmol/g at 273 K and 4.13 mmol/g at 298 K at 1.0 bar. [ABSTRACT FROM AUTHOR]

The cross-linked structure of thermosetting carbon fiber composites makes it difficult to degrade and recycle, especially the non-destructive recovery and recycling of high value-added carbon fiber is a major challenge for the sustainable development of carbon fiber composites. The high-efficiency degradation of chemical health and the high performance of materials are mutually restricted and difficult to balance. We report a epoxy resin networks, prepared through ring-opening reaction of epoxy resin with diselenide-labeled diaromatic amine, that can be turned into catalyst-free vitrimer material by exchange of diselenide bonds. When the diselenide bonds are introduced, specific relaxation times and activation energy of the vitrimer have been measured. Based on the dynamic diselenide bonds, this new vitrimer materials can be reprocessed and repaired upon heating via swift metathesis reactions. In addition, the diselenide crosslinks thermoset materials, which have high modulus and high glass transition temperature, exhibit considerable reprocessability, recyclability and reparability. Furthermore, recyclable carbon fiber reinforced composites (CFRC) are prepared using dynamic diselenide covalent network materials as binders. Epoxy resin with exchangeable diselenide crosslinks to obtain reprocessable, repairable and recyclable fiber-reinforced thermoset composites. [Display omitted] • Specific relaxation times and activation energy of diselenide crosslinks thermoset materials have been measured • Preparation of high T g and self-healing materials fosters domain-general strategy knowledge. • Recyclable carbon fiber reinforced epoxy (CFRC) are prepared using dynamic diselenide covalent network materials as binders. [ABSTRACT FROM AUTHOR]