Which is the best quality of hydroxypropyl methylcellulose produced by horizontal kettle and vertical kettle
The quality of hydroxypropyl methylcellulose produced by horizontal kettle and vertical kettle is good;
1. The quality of hydroxypropyl methylcellulose produced by horizontal kettle and vertical kettle
Hydroxypropyl methylcellulose is a cellulose ether derivative, and its production currently has two process routes: horizontal kettle dry method and vertical kettle solvent method;
1. The production process route of the horizontal kettle dry method is a production process developed in the early stage. The main production process is that the cotton fiber is kneaded and alkalized in a liquid alkali, and then an etherifying agent is introduced for etherification. This dry production process is not conducive to the diffusion and penetration of the etherifying agent, so the etherification reaction time is short, the efficiency is low, the cost is relatively low, the reaction is unstable, the uniformity is poor, the side reactions are many, and the quality of the obtained product is relatively poor.
2. The production process of the standing kettle solvent method is that the alkalization and etherification of cotton fibers are carried out in an inert organic solution, so the diffusion and penetration speed of the reagent is improved, which is beneficial to the mass transfer and heat transfer of the reaction process, so that the reaction is stable. The etherification is uniform, the consumption of the etherifying agent is low, the etherification efficiency is high, the cost is relatively high, and the obtained product is of high quality and stable. At present, the advanced production process of solvent method is mostly used at home and abroad. Different companies use different solvents, and the reaction mechanism is basically the same.
Second, due to the improvement of the horizontal kettle dry production process, the output is large and the cost is slightly lower. regarded as a new type of traditional craftsmanship. It has also been recognized by new cellulose enterprises.