Influence of the surface modification of alumina nanoparticles on the thermal stability and fire reaction of PMMA composites

Abstract

Nanometric aluminum oxide particles were modified by phosphonic acid‐based oligomers of aromatic polyester, polyether, or polydimethylsiloxane (PDMS). The grafting process was characterized by FTIR spectroscopy and thermogravimetric analysis (TGA) showing that covalent bonds must have formed between the oxide and oligomers. The highest yield of grafting was achieved in dichloromethane (CH2Cl2) solvent. Then, nanocomposites were prepared by melt‐blending in a poly(methyl methacrylate) (PMMA) matrix. The best results in terms of thermal stability and flammability were obtained with the bis‐phosphonicpolydimethylsiloxane‐based formulation. With this latter, the peak of heat released rate (pHRR) decreased during the combustion, whereas PyGC/MS experiments led to the conclusion that PDMS‐covered nanoparticles played a role in the composition of the gaseous phase as well. Copyright © 2008 John Wiley & Sons, Ltd.

Surface Modification of Alumina Nanoparticles: A Dispersion Study in Organic Media

“…22 The melt blending of the unmodified as well as the modified particles with PMMA led to well-dispersed NCs structures. Thermal stability and fire behavior of PMMA were improved due to physical and physico-chemical processes involving the presence of the nanometric alumina.…”

“…It is suggested that this compound could act in the condensed phase due to its important thermal stability and could also promote modifications of the degradation pathway of PMMA in the interphase region surrounding the alumina particles. 22 Chemical surface modification of aluminum oxide (AO) NPs with graft copolymer of AO and poly (isobutyl vinyl ether) (PIBVE) (AO-graft-PIBVE) was carried out by ball milling of AO NPs with IBVE in vacuum at low temperature. The surface modified AO NPs with monodispersed particle diameter exhibited structural blue color which was evidenced by photograph, optical spectroscopy (UV-Vis) and SEM image.…”

Synergistic flame retardant effects and mechanisms of aluminum diethylphosphinate (AlPi) in combination with aluminum trihydrate (ATH) in UPR

“…But when adding AlPi and ATH (Fig. 2c, d), the surface presented few blocky structure and sags and crests, but did not appear accumulation phenomenon, which illustrated that ATH was well dispersed in UPR, owing to the good affinity between the hydroxyl groups of ATH and the ester groups of the matrix [22]. Comparing the tensile strength, flexural strength and modulus of UPR and UPR/AlPi/ATH composites, the results are given in Table 3.…”

PEG‐Bis Phosphonic Acid Based Ionic Supramolecular Structures

“…The band at 1662 cm À1 could be attributed to H-O-H deformation of adsorbed water [10] and the absorption peak at 1246 cm À1 can be ascribed to P¼O deformation vibration. [11] Durmus et al [12] assigned a band at 1143 cm À1 to the stretching mode (P ¼ O)…”