Study of the durability of thermosetting resins for use as matrix in fiber reinforced plastic

J.P MORALES ARIAS; MARIANO M. ESCOBAR; ANALIA VAZQUEZ

Buenos Aires

Conferencia; 6th International Conference on Science and Technology of Composite Materials (COMAT 2015); 2015

Instituto de tecnologia y polimeros y nanotecnologia

The selection of the matrix for a Fiber Reinforced Plastic (FRP) for being used as reinforcing material in contact with Portland cement is one important task because the cement produces a high alkaline medium which is in contact with the resin. One of the main obstacles that delay the acceptance of composites in civil applications is the degradation of the resin in water and alkaline medium. As consequence, the study of the effect of alkaline conditions on the thermosetting resin is an important undertaking. This work studied the diffusion properties of unsaturated polyester and epoxy resins. The study takes into account the relationship between the mechanical and absorption properties of them. Alkaline solution (Ca (OH)2 - pH 12.5) and distilled water (H2O ? pH 7) were the immersion medium. Diffusion coefficient is higher when the resins are immersed in water than alkaline solution. In spite of this, the alkaline medium produces higher effect on the unsaturated polyester resin. The greatest reduction of module at the glassy state of the polymer network is produced for the UPR in alkaline medium. The greatest reduction for plasticizing network in the Tg value was observed in epoxy resin in alkaline medium. Therefore the epoxy resin showed a more stable behavior after immersion with the temperature. The samples were tested by dynamic mechanical analyzer (DMA 8000) in single beam mode. The loss of the elastic modulus of epoxy matrix (5.1%) compared to the results of the polyester matrix (16.1%) indicates that the epoxy resin is more resistant to alkali environments than the unsaturated polyester resin.