Journal of Thermal Analysis and Calorimetry

, Volume 102, Issue 1, pp 13–21 | Cite as

A study of thermal–mechanical properties of an automotive coating exposed to natural and simulated bird droppings

  • B. Ramezanzadeh
  • M. Mohseni
  • H. Yari
  • S. Sabbaghian


Biological resistance of coatings can be regarded as one of the main properties in automotive industries. This study aims to investigate the effects of biological materials on the mechanical performance of an automotive clear coat. To this end, two acrylic melamine clear coats containing different melamine cross-linker contents were used. In addition, biological resistance of these clear coats were studied at two different ageing processes including pre-ageing and post-ageing which involve various hot-cold, humid shockings and UV radiation of sunlight. By the aid of optical microscopy, micro Vickers and DMTA analyses, different optical and mechanical properties such as micro hardness, T g, cross-linking density and storage modulus were studied. Results revealed an inverse impact of both biological materials to decrease the clear coats mechanical attributes. In addition, a complicated effect of ageing conditions was observed for both clear coats exposed to these materials. It was shown that the coating having a higher mechanical properties and T g even resulted in a lower biological resistance.


Bird droppings Pancreatin Biological degradation 


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2009

Authors and Affiliations

  • B. Ramezanzadeh
    • 1
  • M. Mohseni
    • 1
  • H. Yari
    • 1
  • S. Sabbaghian
    • 2
  1. 1.Department of Polymer EngineeringAmirkabir University of TechnologyTehranIran
  2. 2.Paint Shop 1Irankhodro Co.TehranIran

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