Anti-crack plaster mortar for outer wall of building and method for preparing anti-crack plaster mortar

Abstract

The invention belongs to the field of building materials, and in particular relates to anti-crack plaster mortar for an outer wall of a building and a method for preparing the anti-crack plaster mortar. The anti-crack plaster mortar for the outer wall of the building comprises the following raw materials in percentage by weight: 30 to 40 percent of cement, 4 to 10 percent of blend, 30 to 55 percent of fine aggregate, 8 to 15 percent of heavy calcium carbonate, 2 to 5 percent of polymer rubber powder, 0.4 to 1.2 percent of anti-crack fiber, 0.2 to 0.6 percent of wood fiber and 0.4 to 1.2 percent of a thixotropic lubricant. The anti-crack plaster mortar for the outer wall of the building is high in tensile adhesive strength and high in workability and flexibility; a water leakage crack is not formed in plaster after eighty high-temperature to water-spraying cycles and thirty heating to freezing cycles; phenomena of chalking, hollowing, peeling and the like are avoided; the anti-crack plaster mortar is high in crack resistance, good in construction property and low in cost, and does not stick to a tool during construction.

Description

technical field [0001] The invention belongs to the field of building materials, and in particular relates to an anti-crack mortar for plastering exterior walls of buildings and a preparation method thereof. Background technique [0002] With the continuous improvement of the requirements for energy saving and environmental protection, the energy saving of residential buildings has become a top priority. As an important energy-saving technology for residential buildings, the thermal insulation of external walls has been greatly developed. At present, among the external wall thermal insulation methods, the method of using thermal insulation lining boards is the most commonly used method, and the surface of the thermal insulation system of thermal insulation boards needs to be painted A layer of anti-crack mortar to achieve the durability of the insulation system. Plastering anti-cracking mortar is a special dry-mixed mortar for the surface layer with anti-seepage and anti-cr...

AI Technical Summary

Problems solved by technology

[0003] The 28d tensile bonding strength of plastering anti-cracking mortar used in the market is only about 0.40Mpa, and its bonding strength is not high, and the water-resistant bonding strength only reaches 0.20Mpa. The plastering layer is prone to cracking and falling off, which affects the service life of the entire insulation system

In order to obtain plastering mortar with higher bonding strength on the market, a larger cement content is used, and the hydration of cement itself will produce a shrinkage effect, and a larger cement content will increase the shrinkage of the mortar, and will increase the mortar The elastic modulus reduces the flexibility of the mortar, causing the mortar to have thermal stress deformation when used on the wall surface, which affects the durability of the anti-cracking mortar.

Images