Production method for continuously producing high-viscosity polymer

Abstract

The invention relates to the field of polymer production, and discloses a production method for continuously producing a high-viscosity polymer. The method comprises the following steps: continuouslyfeeding a prepolymer melt with the intrinsic viscosity of 0.10 to 0.45 dL / g into a final polycondensation reactor; reacting and standing for 30 to 250 min under the conditions that the temperature is220 to 295 DEG C and the absolute pressure is 20 to 2000 Pa so as to prepare the high-viscosity polymer with the intrinsic viscosity of 0.7 to 1.15 dL / g, wherein in the final polycondensation reactor,the prepolymer melt is sequentially treated by a first stirrer and a second stirrer with different rotating speeds. Two stirrers with different rotating speeds and different structures are arranged in the same polycondensation reactor, so a liquid film can still be efficiently updated when the viscosity of the polymer is high, the mixing and mass transfer effects during high viscosity are effectively improved, the intrinsic viscosity of the polymer at the outlet of the reactor can be effectively improved, and the production capacity and the product range of the polycondensation reactor are effectively improved.

Description

technical field [0001] The invention relates to the field of polymer production, in particular to a production method for continuously producing high-viscosity polymers. Background technique [0002] The current production and preparation of polytrimethylene terephthalate (PTT), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), butylene adipate terephthalate Among the final polycondensation reactors of alcohol ester (PBAT), polybutylene succinate (PBS) and other types of polyesters, the final polycondensation reactor is the key equipment in the entire production line and is the final polycondensation reactor for polyester polymerization. Disc reactors and cage frame reactors are widely used now. The viscosity of most of the existing reactors after polycondensation can reach 0.62~0.7dl / g. With the continuous development of new products, the viscosity of the material after polycondensation in the reactor is required to reach 0.95 dl / g or even higher. The t...

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Problems solved by technology

On the other hand, when the polymer liquid film and the annular disc form a whole to rotate together, the flow of the subsequent polymer is blocked, and the surface renewal and polymerization reaction of the subsequent polymer are also restricted, so that the viscosity of the subsequent polymer cannot be further increased.

Therefore, when using the traditional disc reactor to produce polymers with higher viscosity, we can only add another set of viscosifying reactors, which makes the production process longer, and the residence time of the polymer at high temperature is prolonged, which affects the quality of the final product. quality, increased investment costs and production costs

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