Polymer-nanoclay composites have emerged as a new class of advanced organic-inorganic materials with excellent mechanical properties and barrier characteristics with only a few percent of well-dispersed clay reinforcement. These materials demonstrated that it is possible to sensibly enhance barrier properties with particular regard to water and vapour permeability of some resin-based coatings for building construction materials1. However, only few works are aimed to study the behaviour of these materials in relation to the durability of concrete. Some recent results2 indicate significant improvement in moisture penetration resistance when small amount of organoclay, ranging from 1 to 5 wt%, are introduced into epoxy and silane based coatings. Some investigations on the environmental degradation mechanism of epoxy-organoclay nanocomposites due to accelerated UV and moisture exposure3 have highlighted that the nanocomposites coatings exhibit smaller cracks with a less degree of discoloration than the neat epoxy. Other authors4 have found a suitable protective coating to steel rebar to improve the durability of such structures under aggressive exposures, as marine environments. Some surface treatments of natural tuff stone with nanocomposites based on fluoroelastomers and acrylic polymers were already studied by our research group, with very encouraging results5. For this reasons the present work was aimed to investigate the extent of the better moisture barrier performance of nanocomposites and to verify their effectiveness as protective coatings for the concrete. In particular, nanocomposite surface treatments based on two different polymers were prepared and characterized in order to analyze their efficacy on durability of concrete samples, pointing the attention on the understanding of the relations between the improved performance of the treated samples and the different character of the two polymeric resins examined through qualitative and quantitative analyses with particular regard to porosity measurements and transport properties.
NANOCOMPOSITE COATINGS FOR SURFACE PROTECTION OF CONCRETE
SCARFATO, Paola;INCARNATO, Loredana;DI MAIO, Luciano
2012-01-01
Abstract
Polymer-nanoclay composites have emerged as a new class of advanced organic-inorganic materials with excellent mechanical properties and barrier characteristics with only a few percent of well-dispersed clay reinforcement. These materials demonstrated that it is possible to sensibly enhance barrier properties with particular regard to water and vapour permeability of some resin-based coatings for building construction materials1. However, only few works are aimed to study the behaviour of these materials in relation to the durability of concrete. Some recent results2 indicate significant improvement in moisture penetration resistance when small amount of organoclay, ranging from 1 to 5 wt%, are introduced into epoxy and silane based coatings. Some investigations on the environmental degradation mechanism of epoxy-organoclay nanocomposites due to accelerated UV and moisture exposure3 have highlighted that the nanocomposites coatings exhibit smaller cracks with a less degree of discoloration than the neat epoxy. Other authors4 have found a suitable protective coating to steel rebar to improve the durability of such structures under aggressive exposures, as marine environments. Some surface treatments of natural tuff stone with nanocomposites based on fluoroelastomers and acrylic polymers were already studied by our research group, with very encouraging results5. For this reasons the present work was aimed to investigate the extent of the better moisture barrier performance of nanocomposites and to verify their effectiveness as protective coatings for the concrete. In particular, nanocomposite surface treatments based on two different polymers were prepared and characterized in order to analyze their efficacy on durability of concrete samples, pointing the attention on the understanding of the relations between the improved performance of the treated samples and the different character of the two polymeric resins examined through qualitative and quantitative analyses with particular regard to porosity measurements and transport properties.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
