Carbon Fibre Reinforced Nanocomposite Plastics

McConnell [8] has described how in the field of complex, high-performance aerospace components, carbon fibre/epoxy composites are able to meet the multiple-functional 

Although they are still in use today, PMR resins contain methylene dianiline (MDA) a hazardous compound and suspected liver carcinogen. About 80% of the composite parts made with PMR are autoclave cured with the balance being compression moulded. Several formulations have been developed as alternatives to PMR by scientists at NASA s Langley R D Centre (Hampton, VA, USA) and at NASA s Glenn Research Centre (Cleveland, OH, USA). One of these resins, RP-46 was patented in 1991, and offers similar chemistry but uses a different diamine (3,4 -oxydianiline) to reduce toxicity. RP-46 resin has a glass transition temperature of 393 C and it demonstrates particularly high corrosion resistance in composites. 

An alternative to PMR, is offered commercially by the resin supplier and NASA licencee, Moltech Corporation (Blue Ash, OH, USA). Its formulation replaces MDA with 2,2 -dimethyl benzidine and it can endure service temperatures in carbon fibre composites as high as 335 °C. NASA developed another resin based on phenylethynyl terminated PI oligomers for use as engine components. 

Further improvements in polymerised monomeric reactants were achieved by end capping the ethynyl terminated imide with resin precurser agents such as 

4-phenylethynylphthalic anhydride or biphenyl dianhydride based PI which offer toughness and flexibility up to 316 °C in carbon fibre nanocomposites. 

---

Recently, nanostructured carbon-based fillers such as Ceo [313,314], single-wall carbon nanotubes, carbon nanohorns (CNHs), carbon nanoballoons (CNBs), ketjenblack (KB), conductive grade and graphitized carbon black (CB) [184], graphene [348], and nanodiamonds [349] have been used to prepare PLA-based composites. These fillers enhance the crystalUza-tion ofPLLA [184,313,314].Nanocomposites incorporating fibrous MWCNTsandSWCNTs are discussed in the section on fibre-reinforced plastics (section 8.12.3). 

---