Polyamide-carbon nanotubes nanocomposite with electrically conductive properties

This product is particularly used to produce fuel system of the automotive to promote its Electrostatic Discharging (ESD) property.

This product is a polyamide- CNT nanocomposite. Adding CNT improves the tensile strength and impact resistance. Elongation is constant at the yield point (4%) while it decreases at the break one (7%). In addition, CNTs improve the electrical conductivity so that surface and volume conductivity go up to 2.46E-9 (Ω/sq) and 2.12E-8 (S/cm), respectively. The surface and the volume resistivity go down to 4.21E+8 (S/sq) and 9.39E+7 (Ω.cm), respectively. Due to the high anisotropy of the carbon nanotubes, their application enables to obtain polymer materials with a very low percolation threshold, i.e. with low filler content. The interfacial adhesion between CNTs and polymer is also critical to optimize the mechanical and other functional properties. CNTs can increase the capability of polymer to enhance the dispersion and interfacial bonding between the components. It also due to strong electron transfer capability increases the electrical conductivity.

Most polymers are typical insulators with high surface resistivity, tending to acquire strong electrostatic charge buildup by polymers in frictional contact with other materials which can result in very large static voltages that may lead to dangerous discharge spark. Too high surface resistivity prevents control of charge build-up and limits dissipation of static charges. Too low surface resistivity will result in fast electrostatic discharges or arcing from the plastic part. The electrostatic problem can be solved by incorporation of antistatic agents or conductive fillers into the polymer which reduces the surface resistivity. Mixed to the polymer matrix, such conductive fillers form a percolating, conductive network inside the polymer matrix. One of the common conductive fillers involves carbon nanotubes. Owing to the unique mechanical, electrical and thermal properties, CNTs are expected to be ideal filler for the electro-conductive polymer composites. Thus carbon nanotubes are excellent candidates to produce electrostatic dissipative materials and other useful components in electronics. Polyamides (nylons) are wide range groups of polymers that are both crystalline and amorphous materials in which the repetitive units are connected by characteristic amide groups (-CONH-). Nowadays, a lot of researches are focused on electrically conductive fibers and fabrics which can be used as smart materials to regulate electrostatic discharge (ESD) and determine shielding from electromagnetic interference (EMI) and radio frequency interference (RFI).