- June 6, 2021
- Posted by: admin
- Category: News
The smaller the ash content, the better the water retention. On the contrary, the larger the ash content, the worse the water retention.
2.HPMC Manufacturing Process:
A.The horizontal reaction kettle dry process is the early developed production process.
Kneading alkalization of cotton fibers in liquid alkali, and then etherification reaction is carried out with etherifying agent.
This dry process is not conducive to the diffusion and penetration of etherifying agents, so the etherification reaction time is short and the efficiency is low.
The reaction is unstable, the uniformity is poor and the side effects are many. The product quality is relatively poor, but the output is high.
B. The production process of cotton fibers by the solvent method in a vertical reaction kettle is that both alkalization and etherification of cotton fibers are carried out in inert organic solvents.
Therefore, the diffusion and permeation rate of reagent is increased, which is beneficial to mass transfer and heat transfer in the reaction process and makes the reaction stable.
Etherification is uniform, the consumption of etherifying agent is low, and the etherification efficiency is high, the product quality is high and stable.
Therefore, many manufacturers no longer use this process in pursuit of low cost and high output.
Low water retention gel temperature will cause worse water retention at high temperature, which will completely lose water retention.
Generally speaking, the higher the viscosity, the better the water retention, but if the viscosity is too high, the molecular weight of HPMC cellulose will be higher, which will cause negative effects such as heavy scraping.
Too low addition amount will also cause poor water retention.