Layered particle-based polymer composites for coatings: Part II-Stone chip resistant automotive coatings

Especially in the Course of modern automotive coatings comprising a reduced number of layers the resistance towards the stone chipping is becoming an issue. Layered double hydroxide (LDH)-based polymer composites are readily accessible materials and suitable to impart impact resistance to coatings, provided that an accurate understanding of the structure property relations both of the platelets and the composites is achieved. Incorporated into aqueous polymer dispersions the LDH particles are found in the resultant composites in the form of aggregated clusters, polymer intercalated stacks or exfoliated platelets depending on their size and the type of the intercalated anions. In addition LDH particles are found to be effective in the control of the coating layer architecture by affecting the spinodal phase separation of the incompatible polymers. Applied as a primer layer the LDH-based composites provided an excellent stone chip resistance to an automotive coating system. (C) 2008 Elsevier B.V. All rights reserved.