Effect of Al₂O₃ and TiO₂ nanoparticles and APP on thermal stability and flame retardance of PMMA

Abstract

Ammonium polyphosphate (APP)‐based additives and Al2O3 and TiO2 nanoparticles have been incorporated separately or combined at a 15 wt% global percentage in poly(methyl methacrylate) (PMMA). APP–based additive containing melamine phosphate has led to an intumescent behavior during cone calorimeter tests, whereas thermal stability was particularly improved by the use of the oxide nanoparticles. APP with melamine phosphate and Al2O3 combination allowed significant synergism on flame retardance to be achieved, owing to the catalytic action of alumina well‐dispersed nanoparticles, which modified the decomposition pathway of PMMA and the formation of a charred and ceramized structure. Aggregation processes in the case of TiO2 seemed to limit the catalytic action of the surface and did not allow synergism for flame retardance to be observed. Copyright © 2006 John Wiley & Sons, Ltd.

Effect of Nanomaterials onThermal Stability of 1,3,6,8-Tetranitro Carbazole

“…The addition of Al 2 O 3 nanoparticles to TNC decreases the melting and decomposition temperatures of TNC to about 295.2 °C and 395.5 °C, respectively. This trend agreed with a previous study [15] which proposed Al 2 O 3 could accelerate the decomposition process of organic compounds via a heterogeneous catalysis mechanism. Replacement of Al 2 O 3 in the composite by TiO 2 nanoparticles changes the TNC melting temperature to 296.0 °C and the decomposition temperature to around 403.9 °C.…”

“…Replacement of Al 2 O 3 in the composite by TiO 2 nanoparticles changes the TNC melting temperature to 296.0 °C and the decomposition temperature to around 403.9 °C. This effect occurs because the presence of some oxides (such as TiO 2 ) may change the decomposition pathway of the organic compounds by increasing the quantity of releasing heavy components and decreasing the amount of evolved gas [13][14][15]. Furthermore, these nanoparticles give rise to a high diffusivity and better heat transfer through the bulk sample [15].…”

“…This effect occurs because the presence of some oxides (such as TiO 2 ) may change the decomposition pathway of the organic compounds by increasing the quantity of releasing heavy components and decreasing the amount of evolved gas [13][14][15]. Furthermore, these nanoparticles give rise to a high diffusivity and better heat transfer through the bulk sample [15]. However, replacement of TiO 2 in the composite by CNTs causes the melting point to shift to about 294.3 °C and the decomposition temperature to about 432.9 °C.…”

“…Organic/inorganic nanocomposites including one or several nanomaterials have been widely investigated in recent years [13][14][15]. Depending on the number of particles with dimensions in the nanometer range, nanomaterials can be classified into three main categories, i.e.…”

Organometallic Derivatives of Cyclotriphosphazene as Precursors of Nanostructured Metallic Materials: A New Solid State Method

“…the Ti/P contents Nano-sized titanium dioxide particles have been the subject of a great deal of research because of the unique physicochemical properties and applications in the areas of pigments, catalysis and supports, fine ceramics, ion matrices, gas sensors, inorganic membranes, environmental purification and dielectric materials [45][46][47][48]. In the biomaterials field, the use of Ti ceramics as hard tissue replacement implants involves an interaction with the pyrophosphate anion present in bones [49][50][51][52][53][54].…”