There are many kinds of HPMC production processes, mainly including the following four. We will give you a brief introduction in four articles.
1. The production process of the alkali leaching method (step-by-step method) of hpmc
Add the flaky cellulose that has not been pulverized into a special dipping machine, and conduct an alkalization reaction in an alkaline solution of more than 6 times. Then remove the excess alkaline solution, and put the alkaline cellulose into a vertical type with a strong stirring device. Or in a horizontal reactor, it is dispersed in about 8 times the amount of chloromethane, and a certain amount of propylene oxide is added to carry out the reaction. After the reaction, unreacted monochloromethane, propylene oxide and by-product dimethyl ether were recovered. Wash with hot water, dry, pulverize and sieve to get the finished product.
Disadvantages: This process needs to use a large amount of chloromethane as a dispersant, and the reaction process pressure is as high as 3.0MPa. After the reaction is completed, a large amount of chloromethane and dimethyl ether need to be recovered, the consumption of raw materials is high, and it is difficult to produce high-viscosity products. And sewage COD content is high, therefore, this production technology has been eliminated and rarely reused.
The hydroxypropyl methylcellulose HPMC produced by Landcel adopts the advanced HPMC manufacturing process, and the HPMC products are exported to countries all over the world. We have our own hydroxypropyl methylcellulose production plant to ensure direct supply and quality assurance.