Cellulose ether is a general term for a series of products produced by the reaction of alkali cellulose and etherifying agent under certain conditions. Alkali cellulose is replaced by different etherifying agents to obtain different cellulose ethers. According to the ionization properties of substituents, cellulose ethers can be divided into two categories: ionic (such as carboxymethyl cellulose) and non-ionic (such as methyl cellulose). According to the type of substituent, cellulose ether can be divided into monoether (such as methyl cellulose) and mixed ether (such as hydroxypropyl methyl cellulose). According to different solubility, it can be divided into water-soluble (such as hydroxyethyl cellulose) and organic solvent-soluble (such as ethyl cellulose), etc. Dry-mixed mortar is mainly water-soluble cellulose, and water-soluble cellulose is divided into instant type and surface treated delayed dissolution type.
After the cellulose ether in the mortar is dissolved in water, the effective and uniform distribution of the cementitious material in the system is ensured due to the surface activity, and the cellulose ether, as a protective colloid, “wraps” the solid particles and covers them on the outer surface. Form a lubricating film, make the mortar system more stable, and also improve the fluidity of the mortar during the mixing process and the smoothness of the construction.
Due to its own molecular structure, the cellulose ether solution makes the water in the mortar not easy to lose, and gradually releases it over a long period of time, endowing the mortar with good water retention and workability.
Self-leveling ground cement mortar, with low viscosity hydroxypropyl methylcellulose ether. Since the entire ground is naturally leveled with little intervention by the construction personnel, compared with the previous manual smoothing process, the flatness and construction speed are greatly improved. The self-leveling dry mixing time takes advantage of the good water retention of hydroxypropyl methylcellulose. Since self-leveling requires that the evenly stirred mortar can automatically level on the ground, the water material is relatively large. After adding hpmc, it will control the ground The water retention of the surface is not obvious, which makes the surface strength high after drying, and the shrinkage is small, which reduces cracks. The addition of HPMC also provides viscosity, which can be used as an anti-sedimentation aid, enhance fluidity and pumpability, and improve the efficiency of paving the ground.
Good cellulose ether has a fluffy visual state and a small bulk density; pure HPMC has good whiteness, the raw materials used in production are pure, the reaction is more thorough and free of impurities, the aqueous solution is clear, the light transmittance is high, and there is no ammonia, starch and alcohols. Taste, fibrous under microscope or magnifying glass.