Aging of Carbon Fiber Reinforced Plastic During Exposure on an Open Stand and Under a Canopy

Using the method of dynamic mechanical analysis, differences in the aging of Cycom 977-2/IMS carbon fiber reinforced plastic (CFRP) after 7 years of exposure in a warm humid climate under a canopy and on an open stand have been studied. From the temperature dependences of the dynamic storage modulus and dynamic loss modulus during flexural oscillations of samples at a frequency of 1 Hz, the glass transition temperature and the boundaries of the transition from the glassy to the rubbery state of the epoxy matrix of the composite have been determined. Exposure under a canopy promotes structural relaxation and densification of the macrochain network, leading to improved damping properties of the CFRP. Under open atmosphere conditions, under the influence of solar radiation, degradation and loosening of the structure occur in the surface layer of the plate.