To judge the quality of hydroxypropyl methyl cellulose

Now hydroxypropyl carboxymethyl cellulose sales market more and more, the price is not balanced, how to quickly clear the quality of hydroxypropyl methyl cellulose has become a crucial problem! So how to judge the quality of hydroxypropyl methylcellulose? The first thing to look at is the whiteness of hydroxypropyl cellulose; Although whiteness can not be clear whether HPMC is suitable for application, but in the process of processing there are also some bad manufacturers will add a whitening agent, will harm its quality. But generally speaking, the majority of excellent cellulose ether is better whiteness.

Second, to see the fineness of hydroxypropyl methyl cellulose: hydroxypropyl carboxymethyl cellulose particle size of 80-100 mesh, 120 mesh less, hydroxyethyl cellulose HECHPMC about 100 mesh. HPMC for most 60-80 mesh, general methyl cellulose softer, the better dispersion.

Solution of cellulose ether clarity: HPMC put into the water to produce transparent colloid solution, see the higher the resolution, the higher the resolution, that does not dissolve the chemical substance is lower.

When the commodity is heated, it is gelatinized or pooled and subsequently remelted. It is hydrophobic and water-soluble. Concrete is the key bonding and demulsification raw material of water-resistant putty powder. Its water-resistant principle is as follows: In the process of adding water and stirring the redispersible latex powder and cement, the latex powder keeps returning to the original emulsion form, and the latex particles are evenly dispersed into the cement paste. After the cement meets water, the hydration reaction begins, and the Ca (OH) 2 solution reaches saturation and precipitates crystals, and at the same time, ettringite crystals and calcium silicate hydrate colloids are generated. Latex particles are deposited on the gel and unhydrated cement particles. With the progress of hydration reaction, hydration products are increasing, and latex particles are gradually gathered in the void of inorganic materials such as cement, and form a close accumulation layer on the surface of cement gel. Due to the gradual reduction of dry water, The tightly packed redispersed latex particles in the gels and voids condense to form a continuous film, forming a mixture of cement paste interpenetrating matrix, and bonding the cement paste with other powder aggregates.