An innovative testing methodology to evaluate the effect of long-term exposure to a marine environment on Glass Fiber Reinforced Polymers (GFRPs) has been investigated and is presented in this paper. Up to one-year ageing was performed in seawater, to simulate the environment for offshore oil and gas applications. The performance of an epoxy and epoxy-based GFRP exposed at different temperatures from 25 to 80 °C was quantified. The materials were also aged in dry air, to de-couple the thermal effect from the seawater chemical action. Gravimetric testing and Dynamic Mechanical Analysis (DMA) were conducted in parallel on progressively aged specimens. The effect of specimen geometry and the anisotropic nature of diffusion are comprehensively discussed in this paper. For the quasi-infinite specimens, the results show an exponential increase in the seawater absorption rate with temperature. The methodology allowed for the prediction of the diffusivity at a temperature of 4 °C as 0.23 and 0.05 × 10⁻¹³ m²/s for the epoxy and the epoxy-based composite, respectively. The glass transition temperature reduces as sea water is absorbed, yet the sea water effects appear to be reversible upon drying.

We have investigated the formulations and curing parameters to obtain an epoxy foam to be used as thermal insulator layer for a glass fiber reinforced polymer (GFRP). A relevant decrease (50%) of the apparent density of the foam was achieved by adding up to 5 wt % of foaming agent without affecting the glass‐transition temperature (T_g). The mechanical properties were inevitably affected by the foaming, but a remarkable reduction down to 30% of the original value of the thermal conductivity was achieved. Morphological analysis by scanning electron microscopy showed a continuous interface between the epoxy GFRP and the foamed layer. © 2018 The Authors. Journal of Applied Polymer Science published by Wiley Periodicals, Inc. J. Appl. Polym. Sci.2018,135, 46864.