Chemical admixtures for mortar and concrete have both similarities and differences. This is mainly due to the different uses of mortar and concrete. Concrete is mainly used as a structural material, while mortar is mainly a finishing and bonding material. Mortar chemical admixtures can also be classified by chemical composition and main functional use.
Classification by chemical composition
(1) Inorganic salt mortar additives: such as early strength agent, antifreeze agent, accelerator, expansion agent, coloring agent, waterproofing agent, etc.;
(2) Polymer surfactants: This type of admixture is mainly surfactants, such as plasticizers/water reducers, shrinkage reducers, defoamers, air-entraining agents, emulsifiers, etc.;
(3) Resin polymers: such as polymer emulsions, redispersible polymer powders, cellulose ethers, water-soluble polymer materials, etc.;
Classified by main function
(1) Admixtures to improve the working performance (rheological properties) of fresh mortar, including plasticizers (water reducers), air-entraining agents, water-retaining agents, and tackifiers (viscosity regulators);
(2) Admixtures for adjusting the setting time and hardening performance of mortar, including retarders, super retarders, accelerators, early strength agents, etc.;
(3) Admixtures to improve the durability of mortar, air-entraining agents, waterproofing agents, rust inhibitors, fungicides, alkali-aggregate reaction inhibitors;
(4) Admixtures, expansion agents and shrinkage reducers to improve the volume stability of mortar;
(5) Admixtures to improve the mechanical properties of mortar, polymer emulsion, redispersible polymer powder, cellulose ether, etc.;
(6) Admixtures, colorants, surface beautifiers, and brighteners to improve the decorative properties of mortar;
(7) Admixtures for construction under special conditions, antifreeze, self-leveling mortar admixtures, etc.;
(8) Others, such as fungicides, fibers, etc.;
Properties and uses of chemical admixtures for dry powder mortar
The important difference between mortar materials and concrete materials is that mortar is used as a paving and bonding material, and it is generally a thin-layer structure when used, while concrete is mostly used as a structural material, and the amount is also large. Therefore, the requirements for workability of commercial concrete construction are mainly stability, fluidity and fluidity retention ability. The main requirements for the use of mortar are good water retention, cohesion and thixotropy.
Post time: Mar-10-2023