Fibre reinforced polymer composites corrosion

Rebars are polymer fibre reinforced-concrete composites, and they are used as primary structures. It is estimated that replacement of steel reinforcing bars by non-corrosive polymer fibres, i.e., by Kevlar or carbon fibres (which gives rise to Kevlar or C-composite bars) for concrete structures produces structures with one-quarter the weight and twice the tensile strength of the steel bar. It is known that, corrosion of steel reinforcement from carbonation or chloride attack can lead to loss of the structural integrity of concrete structures, and such a danger is non-existent for rebars. Thermal expansion coefficient (TEC) values of these fibres are closer to concrete than that of steel, which provides an another advantage and they have the same surface deformation patterns as the steel bars. In addition, they can provide more economy than epoxy-coated steel bars. 

Van den Emde CAM, Van den Dolder A (1991) Comparison of environmental stress corrosion cracking in different glass fibre reinforced thermoset composites. In Cardon AH, Verchery G (eds) Durability of polymer based composite systems for structmal applications. Elsevier Applied Science, New York, pp 408 17... 

About 30% of all polymers produced each year are used in the civil engineering and building industries(23). Nevertheless, structural plastics such as fibre reinforced composites have so far received little attention by civil and structural engineers, despite some of their obvious advantages such as lightness, handleability and corrosion resistance. This may be due to reservations on credibility grounds or fire resistance properties, as well as to uncertainty on how to design structures with them. Whilst their mechanical properties are in fact fairly well understood, there are a number of... 

Ma CCM, Lee CL, Tai NH, Chemical resistance of carbon fibre reinforced poly(ether ether ketone) and poly(phenylene sulfide) composites. Polymer Composites, 13(6), 435-440, 1992. Enomoto M, Ohashi T, Hata T, Susuki Y, Maeda M, Sato H, Evaluation of corrosion resistance of carbon fibres in hot phosphoric acid, Denki Kagaku, 65(4), 320-325, 1997. 

Polymer-matrix fibre-reinforced composites offer an extremely high stiffness weight ratio to the engineer, and this factor, in combination with resistance to corrosion and relatively low looUng costs, has led to extensive use in stressed applications. 

The paper treats finally the capacity of polymer carbon in form of carbon fibres for the reinforcement of organic polymers. With such advanced composites first time polymer materials are created, the properties of which exceed those of metals in strength, stiffness, resistivity against corrosion and fatigue, the weight of which is but half an order of magnitude less than that of steel. All-carbon composites - these are carbon fibres in a matrix of isotropic polymer carbon - became the high temperature material par excellence for application under most extreme conditions. 

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