Carbon nanotubes (CNTs) is a new type of quasi one-dimensional functional materials, with a large aspect ratio, high strength and modulus, good toughness, low density, more special electronic properties of both. The Young's modulus up to 1.0TPa above [1], carbon fiber than an order of magnitude, about 100 times that of steel; tensile strength of (45 ± 7) GPa, is 20 times as high strength steel; CNTs rich of п electronics, can be used as conductive polymers, polymer composites it with the other to get more excellent performance of the composite material. Meanwhile, CNTs also have good flexibility, the maximum bending angle of more than 110 °, is an excellent modifier composite material and the ideal function of reinforcement. Its superior mechanical properties and thermal stability can greatly improve the strength of polymer matrix composites and toughness, Japanese researchers found that from 1991 has been one of the hotspots in the world of scientific research [2-5]. With the expansion of production and quality of CNTs to improve their application development studies have made some progress, which is an important area of composite materials. Epoxy resin has good mechanical properties, electrical properties and thermal properties, widely used in mechanical, chemical, electrical and electronic and aerospace fields. The biggest drawback is that epoxy resin cured crosslinked brittle, impact resistance and are less able to stress cracking. Nanoparticles in epoxy resin was modified by the introduction proved to be a very effective method, has attracted extensive attention of scholars. Good electrical insulation properties of epoxy resin, combined with other materials, it normally can maintain its good electrical insulating properties, while enhancing the bonding of composite materials, corrosion resistance, workability, etc., especially by adding conductive material can be obtain composite materials with high dielectric constant, but also to improve the dielectric loss [6].
1CNTs and Properties of Epoxy Composites
CNTs / polymer nano-composites during the initial CNTs from the slice orientation began. Ajayan et al [7] prepared by mechanical mixing multi-walled carbon nanotubes (MWNTs) in the epoxy matrix composite materials in the alignment. Jin et al [8] also studied the MWNTs in the epoxy matrix composite alignment, through the thermoplastic polymer with CNTs dispersed in chloroform, and then cast by composite materials. At 100 ℃, CNTs can be achieved with the direction of stretching, and after removal of external forces at room temperature can still reach the same direction, stretching the composite material. Bower et al [9] X-ray diffraction and transmission electron microscopy of the same material and with the degree of sexual.
1.1 Mechanical Properties
CNTs/epoxy composite mechanical properties have been studied extensively [10-12], the radial nanometer size and high tables CNT/epoxy composite materials are reviewed CNTs in polymer surface can lead to Matter easily agglomerated and variation, not only reduces the effective aspect ratio, and likely to cause slippage between the pipe and tube, making the enhanced effect of variation. Salvetat and other first study the dispersion of CNTs/polymer nanocomposites mechanical properties that CNTs can not slip between the reunion and to play an effective enhancement. Gong and other studies of surfactants on the dispersion of CNTs in epoxy resin effects, adding surface active agent, 1% of the CNTs make the polymer glass transition temperature (Tg) increased by the 63 ℃ to 88 ℃, elastic modulus increased by 30%, surface active agents to play the effect of dispersion and plasticizer, the hydrophobic and hydrophilic side near the end of CNTs to form hydrogen bonds with the epoxy resin.
