SU975716A1 - Method for automatically controlling coagulation of synthetic rubber latex - Google Patents

Description

(S) METHOD FOR AUTOMATIC REGULATION OF THE COAGULATION PROCESS OF LATEX SYNTHETIC RUBBER

This invention relates to the automation of latex coagulation processes and can be used in the production of synthetic kits: uchuchs.

There is a method of controlling the process of coagulation of a synthetic rubber latex, carried out by mixing in a latex coagulation apparatus with sulfuric acid, the conclusion is to change the temperature in the coagulation apparatus depending on the flow rate and latex concentration, as well as the concentration of polymer particles in reflux serum C1 3

However, this method has limited possibilities in terms of increasing the tensile strength of rubber and reducing its losses at the stand of the grid of the tape-molding machine due to the presence of disturbances in the pH of the reaction medium in the coagulation apparatus.

The closest to the invention to the technical essence is the method of automatic control of the process of coagulation of synthetic rubber latex, carried out by mixing in a coagulation apparatus .Latex with sulfuric acid, which consists in changing the temperature in

coagulation apparatus depending on the pH of the reaction medium in the coagulation apparatus G2.

The disadvantage of this method is that it does not take into account the change in the magnitude of the surface tension of the latex supplied to the input of the coagulation apparatus.

At large values of surface tension of latex in the coagulation apparatus of latex, the formation of small particles predominates, and small particles give an excessively dense tape that does not have sufficient porosity.

15 This greatly complicates the operation of tape drying and rubber processing, as a result of which the quality of rubber performance, in particular, the tensile strength of rubber, deteriorates. Besides

In addition, particles that are too small can be lost on the mesh of the webbing machine, leaving together with the serum in wastewater.

At low surface tension values of the latex in the coagulation apparatus, the crumb is so large that coalescence of individual particles occurs into large conglomerates.

Claims (2)

The aim of the invention is to increase the tensile strength of the rubber and reduce its losses in the drain of the sieve: tape-molding machine. This goal is achieved by the fact that according to the method of automatic coagulation of synthetic rubber latex, carried out by mixing in the coagulation apparatus the latex with sulfuric acid, which consists in changing the temperature in the coagulation apparatus depending on the pI of the reaction. environment in the coagulation apparatus, adjust the temperature in the coagulation apparatus in direct proportional dependence on the surface tension of the latex at the entrance to the coagulum apparatus. The drawing shows a block-system principle of automatic control of the coagulation process of the divinylstyrene rubber, realizing the proposed Method .. Pa The block diagram shows the coagulation apparatus 1, latex pipeline 2, sulfuric acid pipeline 3, belt molding machine 4, return serum pipeline 5, pipeline 6 and its length th serum, the temperature sensor 7, the regulator 9, the analyzer 10, the pH of the reaction medium, the analyzer 11, the surface tension of the latex and the element 12 oravneni. The system functions in the following way. Latex enters coagulation apparatus 1 via conduit 2, and sulfuric acid via conduit 3. From the coagulation apparatus 1, the reaction mixture enters a strip-cutting machine 4, where a rubber band is formed. Leaking through the mesh of the ribbon casting machine 4, the serum through line 5 is returned to coagulation unit 1 and removed from production through line 6. The temperature in coagulation apparatus 1 is measured by sensor 7 and controlled by regulator 8 with an effect on the regulator installed on the return line to the serum. The pH of the reaction mixture is measured by analyzer 10 and the proportional signal goes to the temperature controller set chamber 8, and to the correction chamber 8 regulator 8 is a signal from the comparison element 12 proportional to the deviation of the lateral surface tension of the latex measured by the analyzer 11 and assignment. The signal from the regulator 8, acting on the regulator 9, changes the temperature in the coagulation apparatus until the mismatch of the regulator 8 is not zero. As the output of the comparison element 12 increases, the reference to the regulator 9 increases, which leads to an increase in temperature in the coagulation apparatus, and vice versa. Thus, the system controls the temperature in the coagulation apparatus by the surface tension of the latex. This allows the size of the particles to be maintained at a predetermined value, which contributes to increasing the tensile strength of the rubber by 10% and reduces its losses in the stock of the webbing machine by 15%. The invention The method of automatic control of the coagulation process of synthetic rubber latex, carried out by mixing in a coagulation apparatus of latex with sulfuric acid, is to change the temperature in the coagulation apparatus depending on the pH value of the reaction medium in the coagulation apparatus, characterized in that in order to increase the tensile strength of the rubber and reduce its losses on the drain of the casting martne grid, the TeMnepaTj py in the coagulation apparatus is corrected in direct proportion to surface tension of latex at the entrance to the coagulation apparatus. Sources of information taken into account in the examination 1. The author's certificate of the USSR 852877, cl. C 08 C 1/14, 1979. 2. USSR author's certificate on application 2882447 / 23-05, cl. C 08 C 1/14, 1979 (prototype). al AND t Yu S