A mechanistic study of degradation of a typical automotive clearcoat caused by bird droppings

作者：Yari Hossein; Mohseni Mohsen^*; Ramezanzadeh Bahram

来源：JCT Research, 2011, 8(1): 83-95.

DOI：10.1007/s11998-010-9273-2

• Enzymatic degradation
• Bird droppings
• Automotive coating
• Hydrolysis
• Pancreatin

This study aims at investigating the degradation mechanism of an automotive clearcoat caused by bird droppings. Natural bird droppings and their synthetic equivalent (pancreatin) were utilized for this purpose. The presence of highly-etched areas on the surface of coatings and structural variations of clearcoat after being attacked by these materials corresponded to a catalyzed hydrolytic degradation. This finding was obtained using different analytical techniques. Based on these studies, three possible hypotheses were presented, including acid catalysis, metal ion catalysis, and enzymatic catalysis. The conditions required for the occurrence of each hypothesis were discussed. It was found that acid and metal ions have a weak contribution to catalyze the hydrolysis reaction of clearcoat, whereas enzymes existing in bird droppings were mainly responsible for this hydrolytic degradation.

• 出版日期2011-1