Polymer00035 - Thermally treated graphite (graphene) have...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
24 increasing silica content with the maximum values at 5% silica content (Yang, et al. 1998). Not only that, the thermal degradation temperature of polyimide/ silica nanocomposites was enhanced significantly from 561 o C to 581, 588, 600 o C by increasing the silica content to 10%, 20%, and 30%, respectively (Chen, et al. 2004). Graphene, a new type of nanofiller for polymer composites, has started to gather research interest in the last few years. Graphene is a flat monolayer of carbon atoms tightly packed into a two dimensional honeycomb lattice (Geim and Novoselov 2007) and exhibits excellent mechanical properties (Dikin, et al. 2007; Lee, et al. 2008) and super thermal stability (Balandin et al. 2008). Currently, there are several methods available to prepare graphene including chemical vapor deposition (Novoselov, et al. 2004), direct sonication (Lotya, et al. 2009) and thermal expansion of graphite (Schniepp, et al. 2006).
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Thermally treated graphite (graphene) have shown wrinkled topology at the nanoscale and likely resulted in mechanical interlocking with the polymer chains (McAllister, et al. 2007). Ramanathan et al. (2008) reported that 0.05% treated graphite in polymethyl methacrylate (PMMA) offered a nearly 30 o C increase in glass transition temperature of the polymer (Ramanathan, et al. 2008). Furthermore, the addition of only 0.6% functionalized graphene (treated in a mixture of concentrated nitric acid, concentrated sulfuric acid and distilled water) to polyvinyl alcohol (PVA) resulted in an 35 and 45% increase in sample elastic modulus and hardness, respectively (Das, et al. 2009). Recently, increasing attention has been paid to polymer-nanocomposites based on specialty polymers such as fluoropolymer. Fluoropolymer is the polymer comprising significant amount of fluorinated repetition units. It has excellent chemical and heat...
View Full Document

Ask a homework question - tutors are online