- HPMC aqueous solution pH in the range of 2 to 12, very stable. Caustic soda and lime water do not have much effect on their performance, but alkali can accelerate its dissolution speed and slightly improve the viscosity.
- HPMC is an efficient water retention agent for dry mortar, reducing mortar water secretion rate and delamination, improving mortar cohesiveness, effectively inhibiting the formation of mortar plastic cracks, and reducing mortar plastic cracking index.
- It is a kind of non-ionic and non-polymeric electrolyte, which is very stable in aqueous solutions with metal salts and organic electrolytes, and can be added to construction materials for a long time to ensure its durability enhancement.
- It improves the mortar work performance, the surface is smooth and firmly bonded to the base, and the operation time can be extended.
Water retention
Achieve internal maintenance, conducive to long-term strength improvement inhibit water secretion, prevent mortar settling, and shrinkage, and improve the anti-cracking property of mortar.
Thickening
Anti-separation improves mortar homogeneity, improves wet bond strength, and improves anti-flow hanging performance.
Air-entraining
Improve the working performance of mortar, as the viscosity of cellulose, gets higher and higher, the longer the molecular chain, the more obvious the air-entraining effect.
Retarding
Prolonging the opening time of mortar.
Starch ether in gypsum mortar
- The higher hydroxypropyl content in starch ethers gives stable hydrophilicity and plays a good role in water retention.
- With different hydroxypropyl content of starch ethers with the same amount of addition, the ability of auxiliary cellulose to retain water is differentiated.
- The substitution of hydroxypropyl increases the swelling degree in water, compressing the space for particle flow, thus playing the effect of viscosity and thickening.
Thixotropic lubricity
Starch ether in the mortar system, rapid dispersion, changes the rheology of the mortar, giving its thixotropic properties, when an external force is applied, the viscosity of the mortar will be reduced to ensure good workability, pumping, giving a smooth feel, when the external force is withdrawn, the viscosity increases, so that the mortar has a good anti-sagging anti-rheology performance, in the putty powder more to improve the putty oil brightness throw It has the advantage of improving the brightness of putty.
Auxiliary water retention
Starch ether has hydrophilic properties due to the role of hydroxypropyl in the system, and when combined with cellulose or added to mortar to a certain amount, it can increase water retention to a certain extent and improve the surface drying time.
Anti-sagging and anti-slip
Excellent anti-sagging effect and shaping effect.
Improve the compatibility of mortar
The particles of RDP powder are dispersed in the system, which makes the system have good fluidity and improves the constructability and compatibility of mortar.
Improve the cohesion of mortar
After the inorganic substances in the mortar system are dispersed to form a film, they are fused with organic substances. It is conceivable that the cement sand in the mortar is the skeleton, in which RDP powder forms a ligament, which makes the cohesion higher, increases the strength, and gradually forms a flexible structure.
Improve the frost resistance of mortar
RDP powder has good flexibility, which can make mortar cope with the cold and heat changes of the outside world, and effectively prevent mortar from cracking due to temperature difference changes.
Improve the anti-cracking strength of mortar
Polymer and cement paste form a complementary advantage, when the external force produces cracks, the polymer can go through the cracks and inhibit the expansion of cracks, thus improving the fracture toughness and deformability of mortar.