Film-Forming Property of Cellulose Ethers

With the rapid development of dry-mix mortars and green construction materials, Cellulose Ethers (CEs) have become one of the most indispensable additives 

in the building materials industry. Beyond their well-known thickening, water-retention, and stabilization effects, cellulose ethers also exhibit excellent film-forming 

properties, which play a crucial role in enhancing the overall performance of construction systems.

1. Mechanism of Film Formation

When cellulose ether is dissolved in water, it forms a stable polymer network structure. As water gradually evaporates, the cellulose chains interlace and bond through 

hydrogen interactions, creating a dense, flexible, and continuous film on the surface of the substrate. This film significantly improves surface compactness, adhesion, and 

flexibility, while enhancing crack resistance and durability of the applied material.

2. Impact on Building Mortar Systems

In tile adhesives, wall putties, self-leveling compounds, and gypsum-based materials, the film-forming behavior of cellulose ether directly affects construction performance 

and long-term stability:

In tile adhesives, the formed film strengthens the bond between the mortar and the substrate, preventing detachment and hollowing.

In wall putty systems, it reduces surface cracking and powdering by controlling moisture loss.

In gypsum products, the film acts as a protective layer, improving surface hardness and water resistance.

3. Synergy with Redispersible Polymer Powder (RDP)

Cellulose ethers often work synergistically with Redispersible Polymer Powders to form organic-inorganic composite films. While cellulose controls water distribution and 

enhances workability, RDP contributes elasticity and cohesive strength after curing. Together, they create a hybrid film that delivers superior adhesion, flexibility, and weather 

resistance, ideal for high-performance mortars.

4. Future Development: Functional Design and Green Film-Forming Technologies

Driven by the demand for eco-friendly and high-performance construction materials, researchers are developing modified cellulose ethers with enhanced transparency, lower 

VOCs, and controlled film-forming rates. These innovations aim to achieve better balance between mechanical strength, flexibility, and sustainability in construction applications.

The film-forming property of cellulose ethers is more than a physical phenomenon—it represents a critical interface mechanism that determines performance stability in modern 

mortar systems. As molecular design and formulation technologies advance, cellulose ethers will continue to play a pivotal role in the evolution of high-quality, sustainable building materials.

Name: Cecilia.Wang

E-Mail:cecilia.wang@jtdf-rdp.com

Mobile:+86 190 3451 3486（Whatsapp）