METHOD FOR MINIMIZING THE TRANSITION TIME FROM ONE QUALITATIVE STATE OF THE POLYMER TO ANOTHER QUALITATIVE STATE OF THE POLYMER IN A POLYMERISATION APPARATUS Russian patent published in 2020 - IPC C08G63/08 G05D11/08 G05D27/00 

FIELD: chemical or physical processes.

SUBSTANCE: invention relates to a method of reducing transition time during change from a first qualitative state of a polymer to a second qualitative state of the polymer in a continuous polymerisation process, carried out in a polymerisation plant. Polymerisation unit includes at least one back mixing reactor, at least one cyclic monomer and at least one process agent, selected from a group comprising catalysts, cocatalysts, polymerisation initiators, comonomers, chain transfer agents, branching agents, solvents and random combinations of two or more of said agents, which are added before and/or during the polymerisation process into at least one back-mixing reactor. Concentration of one or more of at least one added process agent in the feed stream, introduced into at least one backmix reactor, is varied in form of a function of time from a first value associated with a first quality state of the polymer to a final value, associated with second qualitative state of polymer. First quality state of polymer and second qualitative state of polymer are one or more parameters, relating to the molecular weight of the obtained polymer, and/or one or more parameters associated with the composition of the obtained polymer, and/or one or more parameters associated with the structure of the obtained polymer, and/or one or more parameters associated with the amount of polymer obtained. During variation of concentration of at least one added process agent from first value to final value one or more intermediate values are controlled, wherein at least one of one or more intermediate values is closer to a final value than the first value, wherein the absolute difference between at least one of the one or more intermediate values and the first value is greater than the absolute difference between the final value and the first value. One or more intermediate values are maintained for a period of time, which is calculated based only on the residence time in at least one backmix reactor and steady-state correlations between the inlet and outlet of the reactor and/or the polymerisation apparatus, and wherein method is carried out without dynamic simulation.

EFFECT: technical result is the development of an easy method of reducing the transition time during change from the first qualitative state of the polymer to the second qualitative state of the polymer in the continuous polymerisation process, carried out at a polymerisation unit, which is accurate and does not require a controller, sensor(s) and calculations of the dynamic model.

15 cl, 1 ex, 5 dwg