Synthesis and characterization of new hybrid copolymers for high performance coatings application

• Autor(a) principal: Carvalho,A.
• Data de Publicação: 2012
• Outros Autores: Veludo,E., Machado,J., Coelho,J. F. J., Gil,M. H.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://scielo.pt/scielo.php?script=sci_arttext&pid=S0870-11642012000200001
• topic: Hybrid Materials; Radical Polymerization; POSS; High Performance Coatings

Polymeric hybrid materials and their specific functionalization have attracted great interest, due to their chemical, thermal and mechanical properties performance, in relation to their equivalent non hybrids. Siloxane based materials offer great interest due to their excellent chemical, physical and electric properties. The primary structure of the siloxane could be modified either by side chain functionalization or by changing the main chain, forming hybrid materials. This kind of materials could be used in several and diverse areas, namely in protective and high performance coatings. The enhancement of their properties can be achieved by incorporating materials such as polyhedral oligomeric silsesquioxanes (POSS) into their polymeric chain. In this paper are presented two new hybrid polymers, the poly(methyl methacrylate-co-isobutyl acrylate-co-glycidyl methacrylate-co-vinyltriethoxysilane) (POSS_0) and the poly(methyl methacrylate-co-isobutyl acrylate-co-glycidyl methacrylate-co-vinyltriethoxysilane-co-(isobutyl)propyl methacrylate(polisilsesquioxane)(POSS_15). These copolymers were prepared by a radical polymerization, and were designed to have the same structure acrylic, epoxy, silane and POSS fractions, which lead to offer multiple properties with high interest to coating systems due to their epoxy and siloxane groups. The presence of the POSS cage in the hybrid polymeric structure increases the hydrophobic character and the thermal stability. When applied in commercial bi-component anti-corrosive paint formulations, the hybrid copolymers presented good performance, good compatibility properties for the different formulation components without forming agglomerates or phase separation. The coating formulation shows quick drying. These materials presented excellent mechanical properties, good adhesion, flexibility and impact resistance.