Investigation of the relationship between morphology and tribological properties of an epoxy resin based on tetraglycidyl 4,4′‐diaminodiphenylmethane modified with polyetherimide oligomers

Abstract

ABSTRACTIn this paper, polyetherimides (PEI) with two different calculated number‐average molecular weights (Mn) of 5000 and 10,000 g/mol were synthesized and used to modify tetraglycidyl 4,4′‐diaminodiphenylmethane. Three different morphologies (separated phase, bi‐continuous phase, and phase inversion structure) were obtained by controlling molecular weights and content of PEI. Thermal and mechanical characterizations showed that addition of PEI resulted in an increase in thermal stability and tensile strength. Tensile strength of samples with bi‐continuous phase was higher than those with separated phase or phase inversion structure. Influence of morphologies on tribology properties were studied by a ring‐on‐block wear tester. Higher wear resistance was achieved from samples with bi‐continuous phase. It was found that wear life of samples with bi‐continuous phase was almost 100% higher than that of samples with separated phase. This is clearly related to the change in thermal and mechanical properties caused by the change of morphologies. Scanning electron microscope observations of worn surfaces and wear debris of the tested samples showed that tribological behaviors and wear mechanisms were heavily dependent on morphologies. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39863.