According to the two applicable standards for tile adhesives—GB/T 25181-2019 (Ready-mixed Mortar) and JC/T 547-2017 (Ceramic Tile Adhesives)—the tensile bond strength after heat aging must be no less than 0.5 MPa (for C2-type adhesives, the requirement is ≥1.0 MPa).
Testing Method:
- Cure the test specimens under Standard Condition 1 (ambient temperature: 23±2°C, relative humidity: 50±5%, air circulation <0.2 m/s) for 14 days.
- Place the specimens in an oven at 70±3°C for another 14 days.
- After removal, attach pull heads to the tiles using a high-strength adhesive (e.g., epoxy adhesive).
- Return the specimens to Standard Condition 1 for 24 hours, then measure the tensile bond strength at a loading rate of 250±50 N/s.
Recommended Solutions:
Increase the dosage of organic binders (e.g., redispersible polymer powders). If the improvement is marginal, consider upgrading to higher-performance binders, such as:
- Ternary copolymer systems
- Acrylic-based polymers
- Styrene-butadiene-based polymers
These alternatives enhance weather resistance and long-term durability of the tile adhesive.
: How to Improve Heat-Aging Strength?){kind=link}