FACILE FUNCTIONALIZATION OF sp2 CARBON ALLOTROPES WITH A BIOBASED JANUS MOLECULE

Abstract

A simple, versatile, sustainable, not expensive method for the functionalization of sp2 carbon allotropes, both nanosized\ud and nano-structured, without altering their bulk crystalline organization, is presented. Carbon materials available at the\ud commercial scale were used: furnace carbon black (CB), nano-sized graphite with high surface area, and multiwalled carbon\ud nanotubes. A bio-sourced molecule, 2-(2,5-dimethyl-1H-pyrrol-1-yl)-1,3-propanediol (serinol pyrrole), was used for the\ud functionalization. Serinol pyrrole (SP) was obtained from serinol through a reaction with atomic efficiency of about 82%,\ud performed in the absence of solvents or catalysts. Synthesis of serinol pyrrole was performed as well on carbon allotropes as\ud the solid support. Adducts of serinol pyrrole with a carbon allotrope were prepared with the help of either thermal or\ud mechanical energy. Functionalization yield was in all cases larger than 90%. With such adducts, stable dispersions in water\ud and inNRlatex were prepared.Afew layers of graphene were isolated from the water dispersions, and NR-based composites\ud precipitated from the latex revealed very even distribution of fine graphitic particles. Composites were prepared, based on\ud NR, IR, andBRas the rubbers andCBand silica as the fillers, with different amounts of CB–SPadduct, and were cross-linked\ud with a sulfur-based system without observing appreciable effect of functionalization on vulcanization kinetics. The CB–SP\ud adduct led to appreciable reduction of the Payne effect

Facile and sustainable functionalization of graphene layers with pyrrole compounds

“…As reported in the introduction, SP has been shown able to form stable adducts with graphitic substrates [20][21][22]62]. It was commented [21,22] that SP is a Janus molecule, that is a molecule with two faces.…”

“…Such a definition, which comes from the Roman god Janus, has been used in the scientific literature to indicate particles with at least two physically or chemically different surfaces [63,64] and molecules with two moieties, typically one hydrophobic and the other hydrophilic, as in the case of colloids [65] and block copolymers [66]. SP was used to functionalize sp 2 carbon allotrope [20][21][22]62] relying on the interaction of the pyrrole ring the with aromatic substrate. Indeed, the Paal Knorr reaction changes the hybridization of the nitrogen atom, from sp 3 in the amino group, to sp 2 in the aromatic pyrrole ring.…”

“…Stable adducts were prepared and hence sustainable oxidation of the carbon allotropes was achieved [20,22], in particular of graphene layers [21]. Stable dispersions of adducts of carbon allotropes with SP were prepared, both in water and polar environments [20][21][22]62].…”

Putative Inhibitors of SARS-CoV-2 Main Protease from A Library of Marine Natural Products: A Virtual Screening and Molecular Modeling Study

“…The cutoff was 10 Å for Van der Waals forces (the default used by AMBER [50]) and no cutoff was applied to electrostatic forces (using the Particle Mesh Ewald algorithm, [51]). The equations of motions were integrated with multiple time steps of 2.5 fs for bonded interactions and 5.0 fs for nonbonded interactions at a temperature of 298 K and a pressure of 1 atm (NPT ensemble) using algorithms described in detail previously [52,53]. The final system dimensions were approximately 80 × 80 × 80 Å 3 .…”

Edge Functionalized Graphene Layers for (Ultra) High Exfoliation in Carbon Papers and Aerogels in the Presence of Chitosan

“…Functionalization of HSAG was performed with a pyrrole derivative: 2-(2,5-dimethyl-1H-pyrrol-1-yl)-1,3-propanediol (serinol pyrrole, SP) [11,[13][14][15], whose structure and 1 H NMR spectrum are reported in Figure 1 and Figure S1, respectively. SP was obtained from 2-amino 1,3-propandiol with a very high yield and atom efficiency, with water as the co-product of the reaction [11].…”