We investigate the effect of polyimide and poly(amic acid) contents on the properties of epoxy resin. Charpy impact strength increases by 80% and 70% with the addition of 10 wt.% poly(amic acid) and 15 wt.% polyimide, respectively. However, the flexural strength is improved by 95% and 73% (as compared with the neat epoxy resin) by the addition of 5 wt.% polyimide and 5 wt.% poly(amic acid), respectively. Moreover, the addition of 10 wt.% polyimide resulted in a twofold increase in the impact adhesive strength, while the tensile adhesive strength of the epoxy increases by 70% with only 5 wt.% polyimide. The infrared spectra show that the obtained compositions containing polyimide or poly(amic acid) exhibit semiinterpenetrating polymer network structures characterized by a relatively high flexibility and very good mechanical properties.
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The authors are deeply grateful to Mr. Marcin Kostrzewa for the preparation of the FTIR spectra.
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Published in Fizyko-Khimichna Mekhanika Materialiv, Vol.47, No.3, pp.77–83, May–June, 2011.
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Bakar, M., Okulska-Bożek, M. & Zygmunt, M. Effect of poly(amic acid) and polyimide on the adhesive strength and fracture toughness of epoxy resin. Mater Sci 47, 355–362 (2011). https://doi.org/10.1007/s11003-011-9403-8
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DOI: https://doi.org/10.1007/s11003-011-9403-8