Polyimide Nanocomposites and Its Application

Abstract

Polyimide is a polymer of imide monomers. Polyimide has properties like Thermal stability Good chemical resistance, Excellent mechanical properties, High tensile strength, Lightweight flexible, resistant to heat and chemicals. Polyimide is used in various application like EMI shielding, fuel cell, supercapicator, aerospace etc. Polyimide properties can be increased by adding filler like CNT and graphene. The syntheses of various polyimide nanocomposites including diamines and dianhydrides that have been used to make novel polyimides with unique properties, are reported in this review. Properties of polyimide like thermal properties, electrical conductivity, and mechanical properties by adding CNT and graphene is studied in this review. I.INTRODUCTION In this review Article, particular emphasis is given to the polyimide nanocomposite and its various application. Polyimides have been in mass production since 1955. With their high heat-resistance, polyimides enjoy diverse applications e.g. high temperature fuel cells, EMI shielding material and as supercapacitor material, and as separation membrane. Polyimide is also known as engineering plastic. In last years many work has been done by the scientists on polyimide. Mainly work was done on polyetherimide, polyamideimide, polyesterimide, etc. polyimide belongs to the class of high-temperature polymers with balanced chemical and mechanical properties in addition to superior film-forming properties. Mechanical properties ,electrical properties and thermal stability of polyimide can be improved by adding the filler. By adding the filler or forming of nanocomposites there is drastically change in the properties of polyimide can be noticed by many scientist in their research work . Fillers like CNT, graphene, were used to increase the properties of polyimide. Mainly CNT and graphene is used as filler because of their low loading level [1]. CNTs (Carbon nanotubes) are composed of graphene sheet rolled up. CNTs is of two types SWNT and MWNT. CNTs can be considered as ultimate carbon fibers due to ultra high strength (10 to 100 GPa) and modulus (~1.0 TPa) values alongwith exceptional electrical (104-106 S/cm) and thermal properties (3000-6000W/mK) [2]. The higher intrinsic conductivity and aspect ratio of CNTs (100-5000) compared to carbon black allows the formation of conductive composites at low loading of CNTs due to low percolation thresholds (minimum loading level at which a continuous network of conducting particles is formed) resulting in achievement of better electrical conductivity and electromagnetic response at the same loading level. Graphene is a nanoscale materials based on single/multi-layered 2-D graphene sheets have attracted much attention recently due to its unusual properties [3]. Though composite materials employing carbon-based materials are presently dominated by carbon nanotubes, the intrinsic bundling of carbon nanotubes, impurities from the catalysts and high costs have been hampering their application. It has been proposed that these prob...