Poly(N‐vinyl imidazole) grafted silica nanofillers: Synthesis by RAFT polymerization and nanocomposites with polybenzimidazole

Abstract

In this report, we synthesized poly(N‐vinyl imidazole) (PNVI) grafted silica nanoparticles (SiNP) by using RAFT polymerization through grafting‐from approach to demonstrate that the self‐assembled structure of SiNP is the key diving force in improving physical properties of SiNP based nanocomposites. In a multistep synthetic process, well‐defined PNVI chains with tunable molecular weights and surface chain densities were grown from the RAFT agent anchored SiNP surface using N‐vinyl imidazole (NVI) as a monomer. Spectroscopic and thermal analysis confirmed surface grafting of PNVI on SiNP surface and the amount of grafted PNVI chins were also quantified. The mean diameter of the PNVI grafted SiNP (PNVI‐g‐SiNP) particles altered between 50 and 100 nm with the variation of PNVI chain lengths. The present approach is metal‐catalyst free, straight forward, and provides PNVI functionalized SiNP in a simple manner in comparison to the reported methods. Further, these PNVI‐g‐SiNP particles were used as a nanofiller to prepare nanocomposites with Poly(4,4′‐diphenylether‐5,5′‐bibenzimidazole) (OPBI). These nanocomposites displayed significantly higher mechanical, proton conductivity and less acid leaching properties than the pristine OPBI. The anisotropic self‐assembled ordered structure formation of nanofillers in the nanocomposites believed to be the driving force for the enhanced physical properties. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 365–375

Obtainment and Characterization of Hydrophilic Polysulfone Membranes by N-Vinylimidazole Grafting Induced by Gamma Irradiation

“…As a result, the band at 3104 cm −1 from VIM was attributed to the -CH group from the ring. Bands from -CH 2 and -CH 3 groups, at 2950 cm −1 , were also observed [ 43 ]. In addition, distinctive bands, at 1645 cm −1 , indicated the stretch vibration of the vinyl aromatic groups (C=C); whereas, bands at 1510 and 1492 cm −1 described the aromatic C=N and C-N stretching bonds.…”

Sulfonated poly(arylene ether sulfone) functionalized polysilsesquioxane hybrid membranes with enhanced proton conductivity

“…The bishydroxy monomer, 2-[bis-(4-hydroxyphenyl)methyl]-benzoic acid (TP-COOH), and the -CF 3 functionalized monomer, 4,4′-bis(4′-fluoro-3′-trifluoromethyl benzyl)biphenyl (QBF), were prepared, according to procedures reported in the literature (42,43). THSPSA (35 wt% in water) and 3,3′-disodiumsulfonyl-4,4′-dichlorodiphenylsulfone (SDCDPS, >98%) were purchased from Fluorochem and Chemos GmbH, respectively, and were used as received.…”

Vesicular and micellar self‐assembly of stimuli‐responsive poly(N‐isopropyl acrylamide‐b‐9‐anthracene methyl methacrylate) amphiphilic diblock copolymers

“…45 RAFT polymerization is often used to design well-defined and complex architectures because of several advantages, including its accessibility of a wide range of functional monomers and reaction conditions. 38,[46][47][48] Anthracene and its derivatives are very interesting class compounds because of their versatile photophysical and photochemical properties; they are used in various applications, including molecular sensors, triplet sensitizers, and functional polymers. 49 Another advantage of these classes of compounds is that they undergo photodimerization under ultraviolet-visible (UV-vis) light (250-700 nm); because this, they have been well studied in photoresponsive materials.…”

“…The synthesis of multiple SRABCs has been reported by several people with controlled or living radical polymerization techniques, such as reversible addition fragmentation chain transfer (RAFT), nitroxide‐mediated polymerization, and atom transfer radical polymerization . RAFT polymerization is often used to design well‐defined and complex architectures because of several advantages, including its accessibility of a wide range of functional monomers and reaction conditions …”