Preparation and characterization of foamed polyurethane/silicone rubber/graphite nanocomposite as radio frequency wave absorbing material: The role of interfacial compatibilization

• Published in: Composites science and technology Vol. 72; no. 3; pp. 382 - 389
• Main Authors: Shafieizadegan Esfahani, A.R., Katbab, A.A., Dehkhoda, P., Karami, H.R., Barikani, M., Sadeghi, S.H.H., Ghorbani, A.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 07.02.2012; Elsevier
• Subjects: A. Coupling agents; A. Functional composites; Applied sciences; B. Electrical properties; B. Surface treatment; Cellular; Compatibility; Composites; Exact sciences and technology; Forms of application and semi-finished materials; Graphite; Nanocomposites; Nanographite; Nanomaterials; Nanostructure; Plutonium; Polymer industry, paints, wood; Polyurethane foam; Radio frequencies; Technology of polymers; B. Electrical properties; A. Functional composites; Nanographite; A. Coupling agents; B. Surface treatment; Electrical conductivity; Polymer blends; Electrical properties; Dielectric properties; Thermoplastic rubber; Experimental study; Cellular plastic; Compatibilizer; Composite material; Surface treatment; Coupling agent; Microwave absorption; Vulcanizate; Preparation; Graphite; Nanocomposite; Plastics; Permittivity; Silicone elastomer
• ISSN: 0266-3538; 1879-1050
• DOI: 10.1016/j.compscitech.2011.11.030

A novel method for the preparation of radio frequency (RF) wave absorber polyurethane foam (PU) has been developed by impregnation of PU foam in n-hexane solution of room temperature vulcanizing (RTV) silicone rubber (SR) hybridized with graphite nanosheets (GNs) called doping solution. Extent of the GNs dispersion was optimized by the incorporation of a specific type of bifunctional compatibilizer. Insulator to conductive transition threshold as well as electromagnetic wave absorption characteristics of the fabricated nanocomposites was shown to be dependent upon the compatibilizer functionality. All PU/SR/GN nanocomposites generated from bifunctional compatibilizer exhibited higher electrical conductivity with enhanced permittivity implying enhanced formation of conductive networks by GN platelets. Permittivity of the PU/SR/GN nanocomposite based on bifunctional compatibilizer showed to be higher than uncompatibilized counterpart. Electromagnetic reflection loss behavior of the PU/SR/GN nanocomposites exhibited a non-linear correlation with the electrical conductivity. Although all PU/SR/GN prepared nanocomposites exhibited electromagnetic wave reflection loss behavior, but this revealed to be affected by the GN level as well as the size and dispersion state of the graphite nanosheets.