The emergent application of carbon materials as cheap and metal free catalysts has attracted much attention1 and the introduction of different functional groups can improve their application as solid catalysts in organic and thermoset crosslinking reactions. Different methods have been reported concerning the introduction of many functionalities like nitrogen, sulfur and the oxygen containing groups requiring harsh conditions, and just in last years the interest to significantly reduce the environmental impact of the procedures, has driven research toward alternative methods such as ball milling. While ball milling for graphite functionalization has been described by many reports , less attention was paid to carbon black. Here we present the possibility to easily oxidize carbon black into oxidized carbon black (oCB) by using the ball milling procedure in solvent free conditions, providing up to 30% of oxygen content comparable to that one obtained with the more aggressive or metal-based methods. The resulting powder could be used as catalyst for important organic reactions or nanofiller in polymer matrixes. A comparative study with the possible oxidation with hydrogen peroxide, already proposed for high-surface area graphite, was also reported, showing the negligible effect on the functionalization by H2O2 and the greater effectiveness of mechanochemical approach. The reaction, performed without any oxidant and in solvent free conditions, can provide products with different oxidation degree only by changing the milling time. This assures to choose the best reaction condition to guarantee the right amount of catalytic sites and changing its polarity to make it well dispersible in different polymer. matrixes.
EASY OXIDATION OF CARBON BLACK BY BALL MILLING: A GREEN APPROACH
Aida Kiani;Maria Rosaria Acocella
2022-01-01
Abstract
The emergent application of carbon materials as cheap and metal free catalysts has attracted much attention1 and the introduction of different functional groups can improve their application as solid catalysts in organic and thermoset crosslinking reactions. Different methods have been reported concerning the introduction of many functionalities like nitrogen, sulfur and the oxygen containing groups requiring harsh conditions, and just in last years the interest to significantly reduce the environmental impact of the procedures, has driven research toward alternative methods such as ball milling. While ball milling for graphite functionalization has been described by many reports , less attention was paid to carbon black. Here we present the possibility to easily oxidize carbon black into oxidized carbon black (oCB) by using the ball milling procedure in solvent free conditions, providing up to 30% of oxygen content comparable to that one obtained with the more aggressive or metal-based methods. The resulting powder could be used as catalyst for important organic reactions or nanofiller in polymer matrixes. A comparative study with the possible oxidation with hydrogen peroxide, already proposed for high-surface area graphite, was also reported, showing the negligible effect on the functionalization by H2O2 and the greater effectiveness of mechanochemical approach. The reaction, performed without any oxidant and in solvent free conditions, can provide products with different oxidation degree only by changing the milling time. This assures to choose the best reaction condition to guarantee the right amount of catalytic sites and changing its polarity to make it well dispersible in different polymer. matrixes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
