Polyaniline stabilized magnetite nanoparticle reinforced epoxy nanocomposites

Magnetic epoxy polymer nanocomposites (PNCs) reinforced with magnetite (Fe 3O 4) nanoparticles (NPs) have been prepared at different particle loading levels. The particle surface functionality tuned by conductive polyaniline (PANI) is achieved via a surface initiated polymerization (SIP) approach. The effects of nanoparticle loading, surface functionality, and temperature on both the viscosity and storage/loss modulus of liquid epoxy resin suspensions and the physicochemical properties of the cured solid PNCs are systematically investigated. The glass transition temperature (T g) of the cured epoxy filled with the functionalized NPs has shifted to the higher temperature in the dynamic mechanical analysis (DMA) compared with that of the cured pure epoxy. Enhanced mechanical properties of the cured epoxy PNCs filled with the functionalized NPs are observed in the tensile test compared with that of the cured pure epoxy and cured epoxy PNCs filled with as-received NPs. The uniform NP distribution in the cured epoxy PNCs filled with functionalized NPs is observed by scanning electron microscope (SEM). These magnetic epoxy PNCs show the good magnetic properties and can be attached by a permanent magnet. Enhanced interfacial interaction between NPs and epoxy is revealed in the fracture surface analysis. The PNCs formation mechanism is also interpreted from the comprehensive analysis based on the TGA, DSC, and FTIR in this work. © 2012 American Chemical Society

Polyaniline Stabilized Magnetite Nanoparticle Reinforced Epoxy Nanocomposites

Magnetic epoxy polymer nanocomposites (PNCs) reinforced with magnetite (Fe₃O₄) nanoparticles (NPs) have been prepared at different particle loading levels. The particle surface functionality tuned by conductive polyaniline (PANI) is achieved via a surface initiated polymerization (SIP) approach. The effects of nanoparticle loading, surface functionality, and temperature on both the viscosity and storage/loss modulus of liquid epoxy resin suspensions and the physicochemical properties of the cured solid PNCs are systematically investigated. The glass transition temperature (<i>T</i>_g) of the cured epoxy filled with the functionalized NPs has shifted to the higher temperature in the dynamic mechanical analysis (DMA) compared with that of the cured pure epoxy. Enhanced mechanical properties of the cured epoxy PNCs filled with the functionalized NPs are observed in the tensile test compared with that of the cured pure epoxy and cured epoxy PNCs filled with as-received NPs. The uniform NP distribution in the cured epoxy PNCs filled with functionalized NPs is observed by scanning electron microscope (SEM). These magnetic epoxy PNCs show the good magnetic properties and can be attached by a permanent magnet. Enhanced interfacial interaction between NPs and epoxy is revealed in the fracture surface analysis. The PNCs formation mechanism is also interpreted from the comprehensive analysis based on the TGA, DSC, and FTIR in this work

Flame-Retardant Epoxy Resin Nanocomposites Reinforced with Polyaniline-Stabilized Silica Nanoparticles

Epoxy resin nanocomposites reinforced with silica nanoparticles have been prepared at different nanoparticle loading levels. The surface functionality of the silica nanoparticles is manipulated by the phosphoric acid (H₃PO₄)-doped conductive polyaniline (PANI) via a surface initiated polymerization (SIP) method. The improved glass transition temperature (<i>T</i>_g) and enhanced mechanical properties of the cured epoxy resin nanocomposites filled with the functionalized silica nanoparticles are observed compared with those of the cured pure epoxy resin. The flammability and thermal stability behaviors of these nanocomposites are evaluated using microscale combustion calorimeter (MCC) and thermogravimetric analysis (TGA). The heat release rate (HRR) peak of the epoxy filled with functionalized silica nanoparticles is observed to decrease dramatically with increasing functionalized silica particle loadings, indicating a flame-retardant performance from the phosphoric acid-doped PANI

Reinforced magnetic epoxy nanocomposites with conductive polypyrrole nanocoating on nanomagnetite as a coupling agent

The new function of polypyrrole (PPy) to serve as a coupling agent has been demonstrated in preparing conductive epoxy resin nanocomposites with PPy coating on magnetite (f-Fe3O4) nanoparticles. The effects of magnetic nanofiller loading level on the rheological behavior, thermal stability, dynamic mechanical properties, mechanical properties, electrical conductivity, dielectric properties and magnetic properties were systematically studied. Compared with pure epoxy suspension, a reduced viscosity was observed in epoxy nanosuspensions with 5.0 wt% f-Fe3O4 nanoparticles, and the viscosity increased with further increasing f-Fe 3O4 nanoparticle loading. Increased glass transition temperature (Tg) and enhanced mechanical tensile strength were observed in the cured solid epoxy polymer nanocomposites (PNCs) with f-Fe 3O4 nanoparticles. The volume resistivity of the cured epoxy PNCs with 30.0 wt% f-Fe3O4 nanoparticles was decreased almost 7 orders of magnitude compared with the cured pure epoxy (1.6 × 1013 Ω cm). The cured epoxy PNCs exhibited good magnetic properties, and the surface functionality and epoxy matrix have little effect on the magnetic moment of the Fe3O4 nanoparticles. The role of PPy nanocoating on the nanocomposite formation mechanism was investigated by using the Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA) tests. © the Partner Organisations 2014