Long-term thermo-oxidative aging of polymeric syntactic foams

Syntactic foams based on different resins with densities ranging from 0.23 to 0.67 g/cm 3 were fabricated. Long-term thermo-oxidative aging of these materials was conducted at temperatures of 120, 150, 180, 210, 250, and 280°C for 500 hours, and the relationship between density and aging rate was established. The degradation rate increases with decreasing density. This dependence is explained by the structure of the composites. For low-density syntactic foams (below 0.3 g/cm 3 ), this effect leads to rapid aging at elevated temperatures. Accordingly, low-density syntactic foams based on more thermally resistant binders – specifically phenolic triazine and polyimide resins – were also produced. Thermo-oxidative aging of these materials was also conducted. The results demonstrate that these materials exhibit greater thermal stability than those based on epoxy resin.