Synthesis and characterization of dialdehyde cellulose/amino-functionalized MCM-41 core-shell microspheres as a new eco-friendly flame-retardant nanocomposite

Using proper flame-retardant materials when constructing buildings or fabricating devices is the most important fire safety guidelines. The halogen and phosphorus-based compounds are among the most effective flame retardants. However, most of these compounds are recognized to have a harmful effect on human body and the environment during combustion. In this context, we designed and synthesized a new eco-friendly flame-retardant nanocomposite by combining dialdehyde cellulose (DAC) and amino-functionalized mesoporous silica MCM-41 (N-M41). Spherical N-M41 nanoparticles have been successfully prepared in one-pot reaction using tetraethyl orthosilicate and (3-aminopropyl)triethoxysilane (APTES), and then coated with different amounts of DAC through Schiff base reaction between the carbonyl group of DAC and NH2 of APTES. The resulted DAC@N-M41 nanocomposite was characterized by XRD, Fourier transform infrared, scanning electron microscopy, transmission electron microscopy, differential thermal analysis (DTA) and thermogravimetry analysis (TGA). TEM micrographs revealed that this nanocomposite was made up of core-shell nanospheres structure with narrow size distribution (ca. 140 nm). DTA and TGA analysis revelated that the presence of silica within the nanocomposite can effectively increase the char yield, decrease the heat release, and improve the fire performance of the prepared nanocomposite. A mechanism of the reduction in flammability of this nanocomposite has been proposed.

Automated summary

This study presents a new eco-friendly flame-retardant nanocomposite combining dialdehyde cellulose (DAC) and amino-functionalized mesoporous silica MCM-41 (N-M41), showing improved fire performance. The mechanism of reduced flammability of this nanocomposite has been proposed based on experimental data.