Research On The Properties Of Polymer Modified Mortar

Based on the cracking of wall, which are caused by unmatched properties between the new wall materials and traditional ones, in this paper, the main causes of cracking of masonry produced by new wall materials are analyzed. Then the way to solve the problem is put forward from the point of view of materials. Namely, Polymer is used to modify the traditional cement mortar. It improves the strength grade, toughness and the bond strength of the mortar, and decreases the shrinkage of mortar, and also increases the property of crack-resistance greatly. Therefore, the new wall materials would be used widely.Two kinds of polymer modified mortar with good toughness and high bond strength were produced by investigating how five different polymers affect mortar mechanical performance (the compressive strength, the flexural strength, the ratio of flexural strength to compressive strength, the bond strength) in different polymer content and in different curing condition. We studied mix properties, mechanical properties and durability of polymer modified mortar under suited curing conditions compared with common mortar.The mortar cracking status was measured by use of the equipment of steel ring. The development of mortar shrinkage and cracking level is attributed to cracking total weigh W. The experiment results showed that above-mentioned test method can evaluate effectively the cracking status of mortar, the cracking resistance of polymer modified mortar is better than traditional mortar. The bond strength between the polymer modified mortar and four new wall materials are measured by the equipment of self-designed "8" testing method. The experiment results showed that the bond strength between the polymer modified mortar and new wall materials is better than one of traditional mortar and new wall materials.The influences of polymer on hydration of cement in mortar were analyzed by SEM, and the mechanism of polymer modified mortar was discussed.