Application of Amino Acid Gypsum Retarder in Gypsum self-leveling mortar

The core function of amino acid gypsum retarders in gypsum-based self-leveling mortars is to precisely control the setting time, maintain a high fluidity window for the mortar, and ensure stable performance after hardening. The specific functions are as follows:
1. Extending the Fluidity Retention Time
The carboxyl and amino groups in its molecules can complex with the Ca²⁺ in the gypsum hydration system, inhibiting the rapid growth of dihydrate gypsum crystals. This allows the mortar to maintain good self-leveling properties for 30–60 minutes, ensuring sufficient leveling and filling of low-lying areas during large-area construction, avoiding problems such as poor surface smoothness and sanding caused by excessively rapid setting.
2. Optimizing the Hydration Process and Improving Hardened Body Performance
The retarding process does not disrupt the normal development of gypsum crystals, resulting in uniform distribution of hydration products. After hardening, the self-leveling mortar meets compressive strength and bond strength standards, has low shrinkage, and is less prone to hollowing and cracking. It also avoids the strength loss problems caused by excessive use of traditional retarders.
3. Enhanced Construction Compatibility: It exhibits excellent compatibility with water-retaining agents (HPMC), redispersible latex powder, defoamers, and other admixtures in self-leveling mortars, preventing flocculation and segregation. It is suitable for both manual mixing and mechanical pumping, making it particularly ideal for large-area floor leveling projects in shopping malls and office buildings.
4. Compliance with Environmental Requirements: As a chlorine-free and formaldehyde-free organic retarder, it meets green building material standards and can be used in hospitals, schools, and other locations with stringent environmental requirements.
Summary: Amino acid gypsum retarder is an indispensable core admixture in modern gypsum-based self-leveling mortars. By efficiently and controllably delaying gypsum hydration, it resolves the fundamental contradiction between "flowability and setting speed" in self-leveling construction, while simultaneously endowing the material with excellent workability and final mechanical properties.