What are the factors that affect the purity of hydroxypropyl methylcellulose?

The purity of hydroxypropyl methylcellulose in building thermal insulation mortar and putty powder directly affects the quality of engineering construction, so what are the factors that affect the purity of hydroxypropyl methylcellulose? Help you answer this question today.

In the production process of hydroxypropyl methylcellulose, the residual oxygen in the reactor will cause the degradation of hydroxypropyl methylcellulose and reduce the molecular weight, but the residual oxygen is limited, as long as the broken molecules are reconnected, it is not very difficult. Disaster. The most important water saturation rate has a lot to do with the content of hydroxypropyl. Some factories just want to reduce the cost and price, and are unwilling to increase the content of hydroxypropyl, so the quality cannot reach the level of similar foreign products.

The water retention rate of hydroxypropyl methylcellulose also has a great relationship with hydroxypropyl, and for the whole reaction process, hydroxypropyl also determines the water retention rate of hydroxypropyl methylcellulose. The effect of alkalizing, the ratio of methyl chloride to propylene oxide, the concentration of alkali and the ratio of water to refined cotton all determine the properties of the product.

The quality of raw materials, the effect of alkalizing, the control of the ratio of the process, the ratio of the solvent and the effect of neutralization all determine the quality of hydroxypropyl methylcellulose, and some hydroxypropyl methylcellulose is made to dissolve In the future, it is very cloudy like adding milk, some are milky white, some are yellow, and some are clear and transparent. To solve it, adjust from the above points. Sometimes acetic acid can seriously affect the light transmittance. It is best to use acetic acid after dilution. The biggest impact is whether the stirring of the reaction is uniform and whether the system ratio is stable (some materials have unstable moisture content, such as the solvent used for recycling). Many factors are at play. The stability of the equipment and the operation of well-trained operators should produce stable products. The light transmittance will not exceed the range of ±2%, and the substitution uniformity of the substituent groups should be well controlled. Instead of uniform, the transmittance will definitely be fine.

Therefore, good product quality is determined by raw materials, production technology, and other factors. Only by strictly controlling from one to the end can products with stable quality be produced.