Structure to Properties Relations of Polyimide Foams\nDerived from Various Dianhydride Components

Abstract

This work focuses on the influence\nof chain structure on properties\nsuch as the structural, thermal, morphological, and mechanical properties\nof polyimide foams (PIFs) which were prepared by polyester ammonium\nsalt powder foaming process. Results showed that the melt viscosity\nof PEAS is affected by the structure of dianhydrides, which can greatly\ndetermine the foaming process, cell structure, and final properties\nof PIFs. PIF which was derived from 3,3′,4,4′-benzophenonetetracarboxylic\ndianhydride and 4,4′-diaminodiphenylmethane exhibited the highest\ncompressive strength (0.374 MPa-RT, 0.194 MPa-200 °C) and compressive\nmodulus (9.24 MPa-RT, 7.37 MPa-200 °C). All PIFs exhibited excellent\nthermal stability as the initial thermal decomposition temperature\nreached as high as 544 °C. In addition, the thermal conductivity\nof the as-prepared PIFs fell in a range of 38–42 mW m^–1K^–1, which show potential applications in areas\nof aerospace, aeronautics, marine use, and transportation among others.