Method for comprehensively drying liquid rubber and drying device

Abstract

The invention provides a method for comprehensively drying liquid rubber. The method comprises the following steps of: 1) concentrating; and 2) performing thin film evaporation. The method for comprehensively drying the liquid rubber is suitable for drying the liquid rubber with both low viscosity and high viscosity, particularly the liquid rubber of which a liquid rubber solution or emulsion is low in concentration and high in solvent content, and the final product is high in viscosity. By adopting the drying device with a special structure and a combined mode, so that the drying efficiency and the treatment amount of the liquid rubber can be improved greatly, a liquid rubber product with qualified volatile matter can be obtained in a short period of time, and the residence time of the liquid rubber at high temperature can be reduced greatly; and therefore, the change of the performance and appearance of the liquid rubber remained at high temperature for a long time can be avoided.

Description

technical field [0001] The invention relates to a comprehensive drying method and drying device for liquid rubber. Background technique [0002] Liquid rubber is a viscous flowable liquid with an index average molecular weight of less than 100,000. Its main advantages are: easy to operate, can be processed by casting or injection, simple equipment, and convenient construction; it can produce rubber shoes, industrial products to tires Various rubber products; the best processing aids in the rubber industry, such as plasticizers, softeners, co-vulcanizing agents, modifiers, etc.; plasticizers in the plastics industry; potting agents and coating agents in the electronics industry ; and asphalt modifiers. In addition, liquid rubber can also be widely used to make various coatings such as anti-corrosion coatings, low-temperature coatings, electrical insulation coatings, water-soluble coatings and electrophoretic coatings, etc., which have the advantages of toughness and impact r...

AI Technical Summary

Problems solved by technology

But adopt this inventive method liquid rubber solution to be difficult to form thinner liquid film when flowing in this equipment, make the evaporation area of ​​unit volume liquid rubber solution limited, when adopting this inventive method, because the solvent volatilized by the barrier effect of tray is relatively small It is difficult to enter the upper condenser through the tray, which affects the volatilization efficiency of the solvent, and this invention is only suitable for the drying of liquid rubber with a relatively high concentration of the original emulsion (for example, the water content in the original emulsion is 63.2%). The volatile matter content requirement in the product is relatively low (such as volatile matter content<1%, and the volatile matter content requirement of the present invention is less than 0.5%), when the solvent content is larger, that is, when the concentration of the liquid rubber solution is smaller, it is difficult to pass through the method of the invention Obtain the qualified liquid rubber of volatile matter content, especially this inventive method is only suitable for the drying of liquid rubber viscosity less than 450Pa·S viscous material, when the viscosity of viscous material increases further, when for example viscosity is greater than 450Pa·S, viscous When the material passes through the middle hole of the concave-convex surface, the fluidity is poor, and it is easy to block the middle hole, which affects the normal drying of the liquid rubber; In the interim, the drying of end-group modified liquid butadiene rubber was introduced and compared with the stirring drying method. The drying efficiency of the thin film evaporator is much higher than that of the stirring tank, and the residence time of the material at high temperature is short, and the physical properties and appearance change little. , the volatile content is qualified, but this method only mentions the drying of liquid rubber with a number average molecular weight of less than 4000 and a viscosity of less than 70Pa·s, and does not mention the drying of liquid rubber with high molecular weight and high viscosity. When used for drying liquid rubber with high viscosity , will cause the liquid flow at the outlet of the thin film evaporator to be unsmooth, thus affecting the normal operation of the drying process, and this method is only suitable for the drying of liquid rubber with a large liquid rubber content in the liquid rubber solution or emulsion, that is, the solvent content is relatively low, such as about 50% liquid rubber. , when the liquid rubber content in the liquid rubber solution or emulsion is smaller, that is, the solvent content is larger, it is difficult to make the volatile content of the final product qualified

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