1. Water retention: HPMC can significantly improve the water retention of mortar, which is crucial to prevent the mortar from losing water too quickly during the curing process under extreme temperatures, especially in low-temperature environments. Good water retention performance ensures sufficient hydration of cement and improves the strength and durability of mortar.
2. Flexural strength and compressive strength: Under low temperature conditions, HPMC may reduce the flexural and compressive strength of cement mortar specimens after cement hydration due to air entrainment. However, if the cement is hydrated in the dispersion of HPMC dissolved in water, the flexural and compressive strengths of the cement mortar specimens will increase compared with the cement hydrated first and then mixed with HPMC.
3. Crack resistance: HPMC can improve the elastic modulus and toughness of mortar, effectively reduce the occurrence of cracks, improve the crack resistance of mortar, and extend its service life. This is especially important during extreme temperature changes, which can often cause the mortar to crack.
4. Alkali resistance and stability: HPMC can still maintain its excellent performance in an alkaline environment without degradation or performance degradation, thus ensuring the long-term effectiveness and stability of the mortar.
5. Thermal performance: The addition of HPMC can produce lighter materials and reduce weight. This high void ratio helps with thermal insulation and can reduce the electrical conductivity of the material while maintaining approximately a fixed value when subjected to the same heat flux. heat flux. The resistance to heat transfer through the panel varies with the amount of HPMC added, with the highest incorporation of the additive resulting in an increase in thermal resistance compared to the reference mixture.
6. Fluidity and workability: HPMC can make the mortar show better fluidity under low shear force and is easy to apply and level; while under high shear force, the mortar shows higher viscosity and prevents Sag and flow. This unique thixotropy makes the mortar smoother during construction, reducing construction difficulty and labor intensity.
7. Volume stability: The addition of HPMC may affect the volume stability of the mortar. In self-leveling mortar, the addition of HPMC causes a large number of pores to remain in the mortar after the mortar hardens, resulting in a decrease in the compressive strength and flexural strength of the self-leveling mortar.
HPMC has a significant impact on the performance of mortar under extreme temperatures. It can improve the water retention, crack resistance, alkali resistance and thermal performance of the mortar, but it may also affect its strength and volume stability. Therefore, in practical applications, the dosage and specifications of HPMC need to be reasonably selected based on specific environmental conditions and performance requirements to achieve the best mortar performance.
Post time: Oct-26-2024