Hydroxypropyl methylcellulose is used as a raw material substrate to produce oil, which can realize the utilization of total sugar, improve the utilization rate of raw materials, reduce the residual amount of substrate in the fermentation broth, and reduce the cost of wastewater treatment. This hydroxypropyl methylcellulose The prime characteristic is conducive to the optimization of batch, fed-batch and continuous fermentation processes, avoiding a series of problems such as the control of medium composition and dilution rate; it is also conducive to the regulation of the fermentation process.
Hydroxypropyl methylcellulose, the raw material cellulose, can be refined cotton or wood pulp. It is very necessary to crush it before alkalization or during alkalization. The crushing is to destroy the cellulose raw material by mechanical energy. The aggregation state structure of the cellulose macromolecules can reduce the degree of crystallinity and polymerization, increase its surface area, thereby improving the accessibility and chemical reaction ability of the reaction reagent to the three hydroxyl groups on the glucose ring group of the cellulose macromolecule.
Although the synthesis principle of etherification of hydroxypropyl methylcellulose is not complicated, the various environments of alkalization, raw material crushing, etherification, solvent recovery, centrifugal separation, washing and drying involve a large number of key technologies and rich knowledge connotations. For different types of products, each environment has the latest control conditions, such as temperature, time, pressure and material flow control. Auxiliary equipment and control instruments are favorable guarantees for stable product quality and reliable production systems.
Since the performance of hydroxypropyl methylcellulose is similar to other water-soluble ethers, it can be used as a film-forming agent, thickener, emulsifier and stabilizer in latex paint and water-soluble resin paint components.
Make the coating film have good wear resistance, leveling and adhesion, and improve the surface tension, stability to acid and alkali, and compatibility to metallic pigments. Hydroxypropyl methylcellulose has a good effect as a thickener for white water-based polyvinyl acetate paint. The degree of substitution of cellulose ether is increased, and the resistance to bacterial erosion is also enhanced.