Epoxy/Silica Nanocomposites: Nanoparticle-Induced Cure Kinetics and Microstructure

✍ Scribed by Patrick Rosso; Lin Ye

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 170 KB
• Volume: 28
• Category: Article
• ISSN: 1022-1336
• DOI: 10.1002/marc.200600588

✦ Synopsis

Abstract

This study reveals the influence of silica nanoparticles on the cure reactions of a diglycidyl ether of bisphenol A epoxy resin. As soon as the silica nanoparticles are added to the neat resin (1, 3, and 5 vol.‐%), the total degree of conversion increases with an increasing amount of nanoparticles, and the cure reaction shows a more complex autocatalytic behaviour, which can not be described by a traditional kinetic model. Results from subsequent thermo‐mechanical analyses confirm an alteration in the microstructure attributable only to the presence of the nanoparticles in the curing stage. An amino‐rich interphase around the reactive treated particles is formed, which shifts the resin/hardener ratio, and benefits the homopolymerization of the epoxy and leads to a more highly crosslinked epoxy network. At the same time, the nanophase consists of a core‐shell structure with the rigid particle inside and a rubber‐like shell because of the excess hardener in this region.

TEM image of two neighboring silica nanoparticles in the epoxy matrix showing a 2–3 nm altered interphase region.

magnified imageTEM image of two neighboring silica nanoparticles in the epoxy matrix showing a 2–3 nm altered interphase region.