How to devide the pure HPMC and non-pure HPMC.
1. The aqueous solution of pure hydroxypropyl methyl cellulose is clarified with high transmittance and the water retention rate of > 95%; Adulterated HPMC water solution is more than 80 %.
2. It will be fibrous under microscope or magnifier for pure HPMC powder, and granular or crystal will be seen under microscope or magnifier for non-pure HPMC powder.
3. The hydroxypropyl methyl cellulose takes the same amount of 2 samples in the mirror. Then ignite it with fire and wait for the combustion to end, looking at the ashes left on the mirror. The chassis is a flat burning pure hydroxypropyl methyl cellulose. The adulterated hydroxypropyl methyl cellulose base was elevated. The smoldering chassis is flat, showing better cellulose