chapter  2
28 Pages

Carbon Nanotube-Reinforced Nanocomposites .................................... Alan kin-tak Lau

A single-walled nanotube (SWNT), similar to a sheet of graphene, rolls over to form a tube with the longest ends joined together to form a cylinder, and theoretically possesses superior mechanical, electrical, and thermal properties. Such properties are governed by perfect carbon-carbon bonds with a bond length of about 0.142 nm, as shown in Figure  2.1 [1]. In this regard, graphene has been referred to as an inŒnite alternant (only a six-member carbon ring). Mechanical property tests showed that graphene has a breaking strength 200 times greater than steel. However, the process of separating it from graphite, where it occurs naturally, will require some technological developments before it becomes economical enough to be used in industrial processes [2]. For a multiwalled type, a stack of sheets are rolled together, with the separation of each sheet being 0.034 nm. All sheets (hereafter called “the layers” for multiwalled types) attract together by only a weak van der Waals interaction, with this force being very small compared with the inplane carbon-carbon bond. One mole of C-C bonds has a bond energy of 347 kJ/mol. The energy required to break a single C-C bond is 3.74 nN. From Cumings and Zettle’s analysis [3], they found that the movement of inner

CONTENTS

2.1 Structure of Carbon Nanotubes (CNTs) ................................................... 19 2.2 Dispersion Properties of CNT Nanocomposites .....................................22 2.3 Interfacial Bonding Properties ................................................................... 26 2.4 Mechanical Properties and Conductivity of Nanotube-Polymer

Composites .................................................................................................... 31 2.5 Modeling of CNT Nanocomposites ..........................................................34 2.6 CNT Biocomposites .....................................................................................40 2. 7 Conclusion ....................................................................................................42 References ...............................................................................................................43