【摘 要】
：
Durability of cement based materials is one of the main challenges of modern society from a technological and economical point of view.This is so because for many years architects and engineers have r
【机 构】
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Sustainable Construction Division, Tecnalia, Derio 48160, Spain;MATCON, Associated Unit Tecnalia-CSI
【出 处】
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The 14th International Congress on the Chemistry of Cement (
论文部分内容阅读
Durability of cement based materials is one of the main challenges of modern society from a technological and economical point of view.This is so because for many years architects and engineers have relayed in the unique properties of cement composites making them ubiquitous in our cities and infrastructures.However, in spite of their endurance not even cement based materials can escape the effects of time, forcing developed countries to invest an important part of their budget to repair and maintenance works.As a consequence, any initiative devoted to increase durability and/or reduce maintenance costs is most welcomed.Within this framework,self-healing materials present themselves as a promising technology that is hoarding an important research effort worldwide.As a result several different approaches are being simultaneously developed.The one presented in this work consists in the introduction of the healing agent (a two component epoxy resin) inside the matrix during the mixing process.To do so, one of the components has been encapsulated into silica microcapsules to avoid interference with the hydration process.The second component, the hardener, is an amine that is introduced as a functionalization on silica nanoparticles.Upon hydration, functionalized nanoparticles induce a pozzolanic reaction with cement that results in the formation of an amine functionalized matrix.Similarly, silica microcapsules also undergo certain extent of reaction ending up perfectly bound to the matrix.This aspect is crucial because the microcapsules have to break altogether with the matrix in order to liberate the healing resin.
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