Polymer-modified cement-based materials have been widely applied in modern construction fields. Through the introduction of polymers, the performance of cement-based materials has been further optimized, enabling them to meet diverse engineering requirements. The popularization and application of redispersible polymer powder have significantly improved single-component dry-mix mortars in terms of quality controllability, transportation and storage convenience, environmental friendliness, and construction efficiency. The application of this product in specialty dry mortars fully demonstrates the enhancement of the physical and mechanical properties of mortar in both fresh and hardened states by powdered polymers, thereby expanding the applicability of such materials under special working conditions. The synergistic effect between polymers and the cement matrix provides a feasible pathway for preparing high-performance composite materials. Overall, redispersible polymer powder-modified specialty dry mortars hold broad market prospects.

To improve the inherent shortcomings of traditional cement mortar, such as high brittleness and high elastic modulus, redispersible polymer powder is commonly introduced in engineering practice as a key modifying component. This additive can endow mortar with excellent flexibility and tensile bond strength, effectively inhibiting and delaying the initiation and propagation of cracks. As polymers form an interpenetrating network structure with cement hydration products and build continuous polymer films within the pores, the bonding force between aggregates is enhanced, and some internal pores within the matrix are effectively filled. Consequently, the comprehensive performance of the modified mortar after hardening achieves a significant leap compared to ordinary cement mortar.

The dosage of redispersible polymer powder varies according to mortar formulations and application requirements, and its addition ratio directly affects the application performance of the mortar:

- Dosage < 1%: Provides certain improvements in workability and adhesion of the mortar;
- Dosage 1%–2.0%: Significantly enhances the strength, water resistance, and flexibility of the mortar;
- Dosage 2.0%–5%: Forms a network-like polymer film within the mortar, markedly improving both strength and flexibility under various climatic and interfacial conditions.

With respect to the glass transition temperature (Tg) of the polymer powder, **products with Tg below 5°C** inherently possess higher flexibility and are primarily suitable for external thermal insulation composite systems; **products with Tg above 10°C** are mostly used in adhesives and self-leveling mortar systems.

The promotion and application of redispersible polymer powder have fundamentally improved the comprehensive performance of traditional building materials, significantly enhancing key indicators such as adhesion, cohesion, flexural strength, impact resistance, abrasion resistance, and durability of construction products. With their excellent quality and technological content, such modified building materials provide a solid guarantee for the quality of construction projects.