Mortars with Phase Change Materials - Part I: Physical and Mechanical Characterization

Abstract

In a society with a high growth rate and increased standards of comfort arises the need to minimize the currently high energy consumption by taking advantage of renewable energy sources. The mortars with incorporation of phase change materials (PCM) have the ability to regulate the temperature inside buildings, contributing to the thermal comfort and reduction of the use of heating and cooling equipment, using only the energy supplied by the sun. However, the incorporation of phase change materials in mortars modifies its characteristics. The main purpose of this study was the production and characterization in the fresh and hardened state of mortars with incorporation of different contents of PCM in mortars based in different binders. The binders studied were aerial lime, hydraulic lime, gypsum and cement. For each type of binder, different mortars were developed with different content of PCM. The proportion of PCM studied was 0%, 20%, 40% and 60% of the mass of the sand. It was possible to observe that the incorporation of PCM in mortars caused differences in properties such as workability, microstructure, compressive strength, flexural strength and adhesion.

Phase Change Materials for Energy Efficiency in Buildings and Their Use in Mortars

“…For such a reason, the research has moved towards the investigation on mortars for interior and/or exterior coatings, where high values of mechanical strength are not required. More recently, other PCM-mortar systems based on different binders, such as aerial lime [73,74,75,76,77,78,79,80,81,82,83,84,85,86,87], hydraulic lime [71,88,89], and, in some cases, geopolymers [90,91,92,93], have been developed and studied [74,78,80,83,90,92].…”

“…In the examined literature, paraffin compounds [65,70,73,74,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,95,97,100,102,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128] are the most used PCM in mortars. Furthermore, higher hydrocarbons (like octadecane [72,94,101,129,130,131,132], hexadecane [98], or heptadecane [71]), fatty acids or their mixtures [99,106,133,134], and polyethylene glycols [64,96,135] have been extensively examined for these applications.…”

Argamassas eco-eficientes com incorporação simultânea de material de mudança de fase e cinzas volantes

“…A seleção dos materiais levou em consideração trabalhos anteriores [11,[13][14][15][16]. As argamassas desenvolvidas foram baseadas em diferentes materiais: cimento, cinzas volantes, PCM, areia, superplastificante e fibras.…”

“…As placas de gesso com incorporação de microcápsulas de PCM foram um dos principais materiais de construção estudados, devido ao seu baixo custo e facilidade de aplicação [6][7][8]. A incorporação de microcápsulas de PCM em betão e argamassas também foi alvo de investigação [9][10][11][12]. Existem também outros estudos com incorporação de PCM em materiais de construção, como por exemplo painéis de PVC, blocos e tijolos [13][14][15].…”

“…Mais recentemente, diferentes trabalhos foram publicados no que diz respeito à incorporação de microcápsulas de PCM em argamassas. Cunha et al [11] investigaram argamassas aditivadas com PCM baseadas em diferentes ligantes, concluindo que a incorporação de PCM provoca um aumento na relação água/ligante e consequente uma diminuição nas propriedades mecânicas. Outro estudo foi publicado sobre a influência da incorporação de diferentes materiais de mudança de fase, provando-se que a utilização de diferentes tipos de microcápsulas de PCM afeta as propriedades físicas e mecânicas das argamassas [12].…”