SU852878A1 - Methodf of emulsion polymerization process control - Google Patents

Description

(54) METHOD FOR REGULATING THE PROCESS OF EMULSION POLYMERIZATION

12

The invention relates to the field of automating polymerization processes and can be used in the manufacture of synthetic rubber.

There is a method of controlling the emulsion polymerization process carried out in a polymer battery, which involves adjusting the Mooney viscosity of the polymer in the head of the polymer battery by varying the temperature and flow rate of the reaction mixture, as well as the consumption of catalyst 1.

However, the known method has limited: possibilities in terms of improving the accuracy of stabilizing the Mooney viscosity of the polymer obtained due to the presence of branching reactions with increasing catalyst consumption.

The aim of the invention is to improve the accuracy of stabilization of the Mooney viscosity of the obtained polymer.

This goal is achieved by the fact that in the method of regulating the emulsion polymerisation process, carried out in a polymer battery, consisting in controlling the Mooney viscosity of the polymer in the head part of the polymer battery, by varying the temperature and flow rate of the reaction mixture, as well as the catalyst consumption, according to the viscosity values

The muni of the polymer at the output of at least two polymerizers determines the increment of the mooney viscosity of the polymer, stabilizes the value of the specified increment by changing the ratio of the initial monomers fed to the input of the polymerization battery.

The drawing shows a block diagram of the automatic control by which the proposed method can be carried out. The block diagram contains a polymerization battery consisting of series-connected polymerization units 1-3. Divinyl and styrene supplied through pipelines 4 and 5, after being displaced in pipe 6, enter the polymerizer / for mixing with the hydrocarbon mixture, a catalyst is supplied to the inlet of the polymerizer / pipe 7

20 (initiator). The feed of the remaining components of the emulsion polymerization is not shown in the diagram.

When passing through the polymerizers / -3, the monomers undergo a 2o polymerization reaction and the reaction mass is removed via line 8.

To remove the heat of the polymerization reaction through the pipeline 9, the shirts and snakes of polymerization units 1-3 are fed into

30, the refrigerant that is discharged through line 10. The consumption of divinyl is controlled by the sensing element //, the regulator 12 and the actuator 13, and the consumption of styrene by the sensing element 14, the regulator and the actuator 16.

The flow rate of the hydrocarbon charge is measured and controlled by the sensing element 17, the regulator 18 and the actuator 19, and the consumption of the catalyst (initiator) by the sensing element 20, the regulator 21 and the actuator 22.

The temperature in polymerization units 1–3, respectively, is measured using sensors 23–25 and is controlled by regulators 26–28 with effects on actuators 29–31 installed on the respective coolant supply lines.

The Mooney polymer viscosity in the polymerizers / -3 is measured respectively by sensors 32-34. A signal proportional to the value of the Mooney polymer viscosity at the exit of the polymerizer / battery enters the controller 35. The automatic control system contains a computing device 36 and a switching device 37.

At the polymerization output of the battery, the ratio of divinyl to styrene costs is maintained. At the output of battery polymerization unit 1, the value of the Mooney polymer viscosity is measured, and in controller 35 it is compared with its specified value.

When the output signal of the regulator 35 deviates to the larger side, the switching device 37 changes the costs of the catalyst (initiator) and the load, i.e., increases the task to the regulators 18 and 21.

When the output of the regulator 35 deviates to a lower side, the switching device changes the setting of the temperature regulators 26-28, i.e., decreases the temperature of the reaction mixture.

To the output of the computing device

36 signals are received that are proportional to the current values of the Mooney poly viscosity value; at the output of polymerization units 2 and 3, the calculating device 36 calculates the Mooney polymer viscosity increment value on polymerization units 2 3.

Next, the computing device 36 compares the obtained increment value with the predetermined one and produces a signal proportional to the deviation value.

The output of the computing device is the task of the styrene consumption controller 75. Thus, when the output signal deviates to a higher direction, the reference to the styrene consumption regulator 15 decreases and vice versa.

The result of the implementation of the proposed method is a decrease in the standard deviation of the Mooney polymer viscosity value.

Claims (1)

1. USSR author's certificate No. 263873, cl. C08F 2/00, 1968.