The influence of hydroxypropyl methyl cellulose on the water consumption of cement-based materials and the application of hydroxypropyl methyl cellulose
Hydroxypropyl methyl cellulose is a kind of industrial additives, which is widely used in construction. It is mainly used as water retaining agent and retarding agent in mortar cement-based materials to make mortar pumpability, which has an irreplaceable role. Cement-based material is a powder state material, with high strength, setting and hardening fast, ice resistance is also good, and then add an appropriate amount of water stirring will become slurry, hardening in water or air, and can be sand, stone and other materials firmly bonded together. Today, we briefly introduce the influence of hydroxypropyl methyl cellulose on the water consumption of cement-based materials and the application of hydroxypropyl methyl cellulose:
The details are as follows for reference only.
Impact on cement-based materials:
1.When there is more water-cement, the lower the viscosity of cement slurry, the cement slurry in pervious concrete is easy to flow, resulting in the blockage of the bottom pores. When the water-cement ratio is small, the higher the viscosity of the cement slurry, the pervious concrete will not appear flowing, plugging and other phenomena, but its strength is low, pavement is difficult, and the operation time is shorter. The addition of hydroxypropyl methyl fiber can play a thickening effect, can increase the water requirement of cement-based materials, and then increase the output of mortar.
2.When the degree of polymerization of hydroxypropyl methyl fiber is higher, its molecular weight is larger, and the viscosity of aqueous solution is higher. The higher the amount of cellulose ether added, the higher the viscosity of its aqueous solution, however, it is necessary to pay attention to the amount added when using, to prevent the addition of too high, affecting the performance of mortar and concrete.
3.Its solution is similar to most solutions, the viscosity of the solution will decrease with the increase of temperature, and the higher the concentration of cellulose, the greater the impact on temperature.
4.At the same time, it is also necessary to note that cellulose solutions are generally pseudoplastic and have the property of shear thinning, and the greater the shear rate during the test, the smaller the viscosity.
In summary, the cohesiveness of cement mortar will be reduced due to external force, which facilitates the scraping operation of mortar, so that mortar can have good workability and cohesiveness at the same time. When the concentration of hydroxypropyl methylcellulose solution is low and the viscosity is small, the solution will show Newtonian fluid characteristics. When the concentration is further increased, the solution will gradually show pseudoplastic fluid characteristics, and the higher the concentration, the more obvious the pseudoplasticity.
Hydroxypropyl methyl cellulose is used in various industries, especially in the building materials industry is more widely used, belongs to a building AIDS to use, indispensable. For example, plastering mortar, cement-based gypsum, gypsum products, wall sealant, paint and paint remover are used in them, which plays an important role.
The application of hydroxypropyl methyl cellulose in the construction industry is as follows, for reference only:
1.Plastering mortar
Adding an appropriate amount of HPMC can strengthen the adhesion ability of the masonry surface, improve the water retention performance, enhance the strength of the mortar, so as to improve the plasticity and lubrication performance, facilitate construction, greatly improve the construction performance, and increase the benefits of enterprises.
2.cement-based gypsum
Adding an appropriate amount of HPMC can improve its uniformity, which can make the plaster easier to coat, enhance pumpability and flow performance, and improve construction efficiency. At the same time, it has good water retention performance, can extend the working time of the mortar for a certain time, and can also control the penetration into the air, so as to eliminate the micro cracks of the coating and form a smooth surface.
3.Gypsum products
Adding an appropriate amount of HPMC can extend the operation time of the mortar, and also produce a high mechanical strength during the solidification process, and form a better surface coating quality by controlling the uniformity of the mortar.
4.Caulking agent
Adding an appropriate amount of HPMC can effectively improve the surface quality, improve the smooth and uniform texture, and make the bonding surface more firm. It has good water retention performance, can extend the cooling time, and its high lubricity makes the application smoother.
5.paint and paint stripper
Adding an appropriate amount of hydroxypropyl methyl cellulose can prolong the warranty period by preventing solid precipitation, has good high biological stability and compatibility, and its dissolution speed is fast, and it is not easy to caking, which is convenient to simplify the mixing process. Produces good flow characteristics, including spatter and good leveling, ensures a good surface finish and prevents the coating from sagging. Strengthen the viscosity of the paint stripper and the organic solvent, so that the paint stripper will not flow from the surface of the workpiece. For more applications, please refer to: The specific role of hydroxypropyl methyl cellulose in the construction industry