Methylcellulose is white or off-white fibrous or granular powder; odorless and tasteless. This product swells into a clear or slightly turbid colloidal solution in water; it is insoluble in absolute ethanol, chloroform or ether. Rapidly disperse and swell in hot water at 80-90°C, and dissolve quickly after cooling down. The aqueous solution is quite stable at room temperature, and can gel at high temperature, and the gel can change with the solution with the temperature.
It has excellent wettability, dispersibility, adhesiveness, thickening, emulsification, water retention and film-forming properties, and impermeability to oil. The formed film has excellent toughness, flexibility and transparency. Because it is non-ionic, it can be compatible with other emulsifiers, but it is easy to salt out, and the solution is stable in the range of PH2-12. Sodium Carboxymethyl Cellulose This product is the sodium salt of cellulose carboxymethyl ether, which is an anionic cellulose ether, white or milky white fibrous powder or granules, with a density of 0.5-0.7 g/cm3, almost odorless and tasteless , with hygroscopicity. Easily dispersed in water to form a transparent colloidal solution, insoluble in organic solvents such as ethanol.
The pH of the aqueous solution is 6.5-8.5. When the pH is >10 or <5, the viscosity of the glue will be significantly reduced, and the performance is the best when the pH is 7. Stable to heat, the viscosity rises rapidly below 20°C, and changes slowly at 45°C. Long-term heating above 80°C can denature the colloid and significantly reduce the viscosity and performance. It is easily soluble in water, and the solution is transparent; it is very stable in alkaline solution, but it is easily hydrolyzed when it encounters acid, and it will precipitate when the pH value is 2-3, and it will also react with polyvalent metal salts. Hydroxypropyl methylcellulose, also known as hypromellose and cellulose hydroxypropyl methyl ether, is made of highly pure cotton cellulose as raw material, which is specially etherified under alkaline conditions.
Soluble in water and most polar c and appropriate proportions of ethanol/water, propanol/water, dichloroethane, etc., insoluble in ether, acetone, absolute ethanol, and swells into a clear or slightly cloudy colloid in cold water solution. The aqueous solution has surface activity, high transparency and stable performance. HPMC has the property of thermal gelation. The product aqueous solution is heated to form a gel and precipitates, and then dissolves after cooling. The gelation temperature of different specifications is different.
Post time: Feb-24-2023