How to Identify the Advantages and Disadvantages of Hydroxypropyl Methylcellulose

How to identify the advantages and disadvantages of HPMC?

1) Whiteness of HPMC: Although whiteness can not determine whether HPMC is easy to use, and if whitening agent is added in the production process, its quality will be affected. However, most good products have good whiteness.
2) Fineness of HPMC: the fineness of HPMC is generally 80 mesh and 100 mesh. The finer the fineness, the better in general.
3) Transparency of HPMC: put HPMC into water to form transparent colloid, and then look at its transmittance. The greater the transmittance, the better, indicating that there are less insoluble substances in it. The permeability of vertical reactor is generally good, but that of horizontal reactor is worse.
4) Proportion of HPMC: the larger the proportion, the heavier it is. It is generally because of the high content of hydroxypropyl in it. If the content of hydroxypropyl is high, the water retention is better.
Comparison of advantages and disadvantages of hydroxypropyl methylcellulose
1) HPMC of pure hydroxypropyl methylcellulose is loose in visual condition, and its bulk density is small, with the scale of 0.3 – 0.4/ml.
Poor quality HPMC has very good fluidity and more heavy handle, which is significantly different from the appearance of authentic products.
2) The pure HPMC aqueous solution is clear and transparent, and the water retention rate is more than 97%.
The water retention rate of HPMC is difficult to reach 80%.
3) Pure HPMC should not smell ammonia, starch and alcohols.
Inferior HPMC usually can smell all kinds of flavors, even if it is tasteless, it will feel heavy.
4) The pure HPMC powder is fibrous under microscope or magnifying glass.
The inferior HPMC can observe granular solid or crystal under microscope or magnifying glass.