Engineering Analysis of Tg and MFFT in Performance Mortars

Engineering Analysis of  Tg and MFFT in Performance Mortars

In polymer chemistry, glass transition temperature (Tg) and minimum film-forming temperature (MFFT) dictate performance under real-world ambient conditions. RUICO 9608A SBR Latex is engineered with an optimal balance: a Tg of 6°C and an MFFT of 6°C.

The minimum film-forming temperature defines the threshold below which polymer emulsion droplets cannot deform and fuse into a continuous, cohesive film. An MFFT of 6°C enables rapid room-temperature coalescing under typical jobsite conditions without requiring volatile organic coalescing solvents. This low-VOC profile aligns with international environmental standards and green building certifications.

Meanwhile, a Tg of 6°C provides a balance between ambient flexibility and mechanical load-bearing capacity. Emulsions with excessively low Tg values can yield soft, tacky polymers that compromise compressive strength, while excessively high Tg values produce brittle films prone to cracking under minor substrate deflection. RUICO 9608A strikes the ideal middle ground: the elastomeric butadiene segment delivers elongation and crack-bridging capability, while the rigid styrene segment provides high compressive strength and chemical resistance.

With a solid content of 48±1wt%, formulators achieve cost-effective polymer loading without adding excess water, preserving low water-to-cement ratios critical for high-strength formulations.