Abstract

Cross-linking is known as a chemical process to improve the mechanical properties by adding polymer. Therefore, the pore walls of aerogels can be strengthened by coating with polymer. In this study, the mechanical properties of a cross-linked monolithic silica aerogel have been examined by nanoindentation tests at different temperatures. Creep compliance values were analyzed as a function of time by linear viscoelastic equations using the test data of nanoindentation. It is determined that the creep compliance values obtained from nanoindentation are much higher than that of compressive test. Additionally, from the relaxation modulus curves, it can be expressed that the aerogel sample used retains its general long-term viscoelastic behavior at elevated temperatures. 

Key words: Silica aerogel, nanoindentation, creep behavior, temperature test, linear viscoelasticity, depth-sensing indentation.

Abbreviation

 DSI, Depth-sensing indentation; SMP, shape memory polymer; RT, room temperature.