Abstract
Specialized polymer resins play a critical role in the material selection and implementation of an engineered fiber reinforced polymer (FRP) composite repair system compatible within a hostile chemical environment. In a corrosive environment, gaseous or liquid chemicals can penetrate the fibers through the resin matrix and cause premature failure by multiple means including improper curing, diffusion, osmosis, embrittlement, microcracking, and swelling of the laminate. As a result, the choice of fiber types as well as the resin formulation of is critical to determine the design life, ensure the best anti-corrosion protection, and minimize the risk of repair failure. This paper presents the findings of a series of experiments that was conducted to identify the resistance of a novolac based epoxy resin and bi-directional E-glass fabric architecture commonly used in FRP repairs and reinforcements of steel pipes transporting an array of chemicals used within the petrochemical and refining industry. Composite coupons were tested in a variety of chemicals, acids, and solvents commonly used within processing facilities to evaluate their resistance to attack. Pre- and post-soak tensile tests are compared to evaluate the effect of the chemicals on the composite repair's strength. Recommendations are made on the suitability of utilizing a novolac based epoxy for specific applications. Chemical resistance testing was performed per ASTM(1) 543 standards, and tensile testing was performed in accordance with ASTM(2) 3039.
