Dry mix mortar additives Redispersible Polymer Powder

Dry mix mortar is a formulated system that uses cementitious materials, aggregates, and chemical

additives to achieve specific application and performance requirements.

Among these additives, redispersible polymer powder (RDP) is used to modify properties such

as bonding strength and flexibility. The appropriate RDP grade depends on the type of mortar

and the performance required from the finished formulation.

What Is RDP Used for in Dry Mix Mortar?

RDP is a polymer powder designed for use in dry mix mortar. When selecting an RDP, formulators

should first identify the required performance rather than simply choosing a general purpose polymer.

Typical selection factors include:

1) Bonding strength

2) Flexibility

3) Waterproofing, where required

4) Compatibility with the complete mortar formulation

The practical selection process is:

Mortar application → Required performance → RDP grade → Formulation testing

How to Select RDP for Different Mortar Applications

Different dry mix mortar applications may require different polymer functions.

Tile Adhesive, Wall Putty and EIFS

When bonding strength and flexibility are the main requirements, JINT™-502 or JINT™-740 

can be evaluated. Both are listed as high-bonding-strength RDP grades for wall putty, tile 

adhesive, and EIFS, with bonding strength and flexibility as their stated functions.

For a universal-grade option, JINT™-503 is listed for wall putty, tile adhesive, and EIFS, with

bonding strength and flexibility. It can be considered when a general RDP grade is required for these applications.

Waterproof Mortar and Other Applications Requiring Waterproofing

When waterproofing is an additional formulation requirement, JINT™-745 can be considered.

Its product page lists bonding strength, flexibility, and waterproofing as its functions, and lists

wall putty, tile adhesive, and joint filler among its applications.

RDP Should Be Evaluated with the Complete Formulation

RDP is only one component of a dry mix mortar system. Cement, fillers, cellulose ether, water level,

and other additives can all affect the final performance.

For an initial laboratory comparison, keep the base formulation, RDP dosage, mixing procedure, and curing conditions consistent.

Depending on the application, compare:

1) Bonding strength

2) Flexibility

3) Water-related performance where relevant

4) Fresh-mortar workability

The final RDP grade should be selected based on the performance of the complete mortar formulation rather than the polymer powder alone.

Conclusion

The right RDP for dry mix mortar should be selected according to application requirements and target performance.

For applications requiring bonding strength and flexibility, JINT™-502, JINT™-503, or JINT™-740 can be evaluated

according to their stated product functions and applications. When waterproofing is an additional requirement, 

JINT™-745 is the more directly aligned option based on its product-page functions.

Laboratory testing in the actual mortar formulation should be used to confirm the final selection.

Name: Molly.Wang

E-Mail:molly.wang@jtdf-rdp.

Mobile:+86 156 5045 0156（Whatsapp）