Evaluation of cementitious repair mortars modified with polymers

Abstract

The aim of this study was to evaluate the effects of added polymers on the properties of repair mortars. Two types of polymers, ethylene vinyl acetate and polyvinyl acetate-vinyl carboxylate, were used as a replacement for 3%, 5%, and 8% of the cement (by weight). All tests were conducted using two water-cement ratios of 0.5 and 0.6. The effectiveness of the repair materials was evaluated according to setting time, drying shrinkage, thermal expansion, compressive strength, and bond strength. Specimens containing polyvinyl acetate-vinyl carboxylate at a water-cement ratio of 0.5 presented the highest compressive and bond strength. Specimens containing ethylene vinyl acetate presented strength characteristics exceeding those of the control at 28 days. The drying shrinkage of polyvinyl acetate-vinyl carboxylate specimens was similar to that of the control. At a water-cement ratio of 0.5, the thermal expansion of polyvinyl acetate-vinyl carboxylate specimens was lower than that of ethylene vinyl acetate specimens; however, at a water-cement ratio of 0.6, the thermal expansion was independent of the type of polymer.

Redispersible polymer powder modified cementitious tile adhesive as an alternative to ordinary cement-sand grout

“…According to the work of Weng et. al [74], for a water-cement ratio of 0.5, the drying shrinkage rate increased from 0.0128% (reference) to 0.0224% for the addition of 8% EVA powder whereas addition of 8% VA/VeoVa powder increased it to 0.0159% which is slightly less efficient than EVA addition. Better results were achieved when the water-cement ratio was increased to 0.6 and like before, EVA addition showed better rate than the VA/VeoVa addition.…”

Study on High Performance Polymer-Modified Cement Grouts

“…Acrylic resin (AR) is one of the common polymeric compounds used for the manufacturing of polymer-modified cementitious composites, such as mortars and concretes [23][24][25][26][27][28]. It is a colloidal solution of very small dispersed particles with sizes varying from 0.04 to 0.2 μm which are dispersed in water.…”

Propriedades da argamassa modificada com polímeros redispersíveis de etileno-acetato de vinila (EVA)

“…Assim, essa modificação pode resultar na redução de seu módulo de deformação e, portanto, permitir maior tenacidade ao material. Ainda, como observado na literatura (OHAMA, 1995(OHAMA, , 1998MEDEIROS;HELENE;SELMO, 2009;TABASSI, 2012TABASSI, , 2013WENG, 2017), as argamassas modificadas tendem a apresentar melhor aderência aos substratos, menor retração e absorção de água, alta resistência química e menor tempo de cura, propiciando, assim, características desejáveis para essa aplicação e garantindo, também, durabilidade superior às argamassas convencionais. A adição de polímeros também pode melhorar o desempenho da ZTI, agindo como ponte entre a matriz cimentícia e os agregados (AHMED, 2011).…”