Morphologies, failure polymers, strength

Crucially, structure of CNTs and polymers plays a key role on mechanical properties and load-transfer of nanocomposites. Efficient load-transfer is only possible when adequate interfacial bonding strength is available. Interfacial failure may compromise the reinforcement effect and then the full potential of CNTs may not be realized (11). Therefore, it is of great importance to understand the effect of molecular structure, interfacial structure and morphology characteristics on the tensile properties of nanocomposite materials. 

The existence of tie molecules and/or tie fibrils was initially demonstrated by Keith and Padden (19, 20) via electron microscopy. The relationship of these morphological structures to the mechanical strength and deformation behavior of polymers has been demonstrated by Peterlin (21) and by Becht, DeVries, and Kausch (22). Fracture during low strain rate tensile failure can be expected to occur along a path of mini-... 

Plastics analysis can be broadly grouped into two main categories. Physical analysis refers to the evaluation of the physical behavior of the material. Properties such as strength, thermal behavior, and flow properties fall into this category, as do failure and morphological characteristics. Chemical analysis seeks to evaluate the compositional characteristics of the polymer. The combination of these two broad approaches has been used successfully to correlate the behavior of plastics to their composition. 

The imiformity and stability of nanotube dispersion in polymer matrix are probably the most fundamental issue for the performance of composite materials. A good dispersion and distribution of CNTs in the polymer matrix minimizes the stress concentration centers and improves the uniformity of stress distribution in composites [80]. On the other hand, if the nanotubes are poorly dispersed within the pol mier matrix, the composite will fail because of the separation of the nanotube bundle rather than the failure of the nanotube itself, resulting in significantly reduced strength [117], Mazinani et al. studied the CNT dispersion for electrospun composite fiber, as well as its effect on the morphologies and properties of electrospun CNT-polystyrene nanocomposite [42]. They demonstrated that the CNT dispersion is an important controlling parameter for final fibers diameter and morphology. 

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