Views: 2 Author: Site Editor Publish Time: 2022-02-18 Origin: Site
When it comes to mortar admixtures, you should first understand the effect of ordinary mortar on performance. As the basis for the selection of mortar admixtures, HPMC hydroxypropyl methyl cellulose is one of the best.
The commercialization of mortar is mainly the market reform made by the state in terms of environmental protection and quality control. The mortar is generally mixed with dry powder, which causes a lot of dust pollution. The other is the guarantee of construction quality. Originally, ordinary mortar was mostly mixed mortar, among which, besides cement and sand, lime paste was used in a relatively large amount. Lime paste has three main functions: water retention, workability, providing mortar strength and reducing shrinkage stress caused by cement hardening through coagulation and expansion. Therefore, many digesters were originally seen on the construction site, and the production of limestone was energy-intensive and polluted, so the country gradually banned the application of lime plaster. Therefore, the admixture of commercial mortar is to replace the role of lime paste, so it has water retention, improvement of construction and heterogeneity, and reduction of dry shrinkage stress of cement has become the selection standard of mortar additives. HPMC Hydroxypropyl methylcellulose has been used in building materials in recent years. The industry has played a great role, and many new types of mortar have been developed. And hydroxypropyl methylcellulose HPMC is not harmful to the environment, and it is also an environmentally friendly mortar admixture.
At present, the main additives for mortar are as follows:
1.Thickening powder ,Thickening powder is a mortar modifier developed by the Shanghai Academy of Construction Sciences. Its performance in all aspects is still good. The transportation cost is relatively large compared to the low-cost thickening powder, making it a nationwide market. Internal promotion encountered a bottleneck. At present, the thickening powders all over the country are not thickening powders in the true sense.
2. Mortar King is actually a kind of air-entraining agent whose main component is sodium dodecyl sulfonate, etc. It only has air-entraining function in mortar. It is far from replacing lime paste in the true sense, and it is not beneficial to the quality of the project. Air entrainment will inevitably lead to a decrease in the strength of the mortar, and the lack of water retention also makes the appearance of valley cracking tend to be common.
3. Bentonite ,No matter what kind of bentonite, its water retention and construction performance are good, but its fatal weakness is that the dry shrinkage is relatively large, which is the same direction deformation for the dry shrinkage of cement, which strengthens each other and is more prone to cracking.
4. HPMC Hydroxypropyl methyl cellulose has absolute advantages in terms of water retention performance and construction improvement, and can effectively reduce the shrinkage and cracking of pulp, and improve the production of mortar. out rate. Hydroxypropyl methylcellulose has an air-entraining function. When adding hydroxypropyl methylcellulose, consider the dosage, viscosity, and air-entraining properties.
Hydroxypropyl methylcellulose has many advantages, and also has a lot of room for development in the building materials market.