Mechanically robust, thermally conductive and flame retardant polydimethylsiloxane composites decorated with a nitrogen/phosphorus-functionalized carbon nanotubes-montmorillonite interconnected network

Abstract

Polymer-matrix composites with superior fire safety, thermal conductivity, and mechanical performance are increasingly in demand due to the rapid development of advanced electronic devices. Herein, a nitrogen/phosphorus-functionalized carbon nanotubes-montmorillonite (CNTs-N,P-Mt) hybrid was constructed and self-assembled in polydimethylsiloxane (PDMS) to form a three-dimensional (3D) interconnected network structure, based on the geometrical constraint of sheet-like Mt. The 3D CNTs-N,P-Mt network enabled the PDMS-based composite with enhanced mechanical properties, thermal conductivity and flame retardancy simultaneously. When 10.0 wt.% CNTs-N,P-Mt hybrids were incorporated, tensile strength and thermal conductivity of the obtained PDMS-based composites were 225.0 % and 70.4 % higher than those of pure PDMS; meanwhile, such composite exhibited the smoke production rate of 0.04 m²▪s⁻¹ and peak total smoke production of 3.51 m², which were 48.1 % and 30.3 % lower than those of pure PDMS (suggesting superb smoke suppression properties). This work provides valuable insight into developing multifunctional polymer-based packaging materials for application in advanced electronic devices.