Method for producing copolymerized polypropylene by using propylene gas phase polymerization device

Abstract

The invention discloses a method for producing copolymerized polypropylene by using a propylene gas phase polymerization device, wherein a sticking inhibitor is added during the polymerization, and isa refined organic compound. According to the present invention, LPN is replaced with the refined organic compound, such that the component of the inert gas in the reactor can be reduced, the ventingamount can be reduced, the polymerization efficiency of the catalyst can be improved, the smooth operation of the device can be achieved, and the ethylene-propylene impact-resistant product with highethylene content can be obtained; and the sticking probability of the ethylene-propylene copolymer can be reduced after the organic particles are added while the organic particles and the kettle wallare subjected to collision friction to form static electricity, and the alcohol-based substance enters the reaction kettle after being atomized or vaporized through the power of the fan, and can neutralize the static electricity, such that the polymerization can be stably performed for a long time.

Description

technical field [0001] The invention relates to a method for producing copolymerized polypropylene with a propylene gas phase polymerization device, belonging to the field of polypropylene preparation. Background technique [0002] Polypropylene is a typical partially crystalline thermoplastic resin, and its good performance-price ratio determines that it has a wide range of applications. In recent years, with the rapid development of the automobile industry, high-speed trains, construction industry, electronic telecommunications industry and the high performance of polypropylene products, the output and demand of polypropylene have increased significantly, becoming the fastest growing general-purpose plastic in the past ten years. Annual demand growth of up to 8%. With the development and application of production technology and new catalysts, many high-performance polypropylene products appear in the market, mainly in terms of impact resistance, high rigidity, transparenc...

AI Technical Summary

Problems solved by technology

[0006] 1) With the addition of a large amount of LPN, a large amount of inert gas accumulates, which reduces the partial pressure of monomers effectively participating in the polymerization, resulting in a decrease in polymerization production efficiency. Roughly estimated, the partial pressure is about 50% when the nitrogen gas is balanced, that is, compared to no nitrogen gas, Polymerization production efficiency drops by at least 50%;

[0007] 2) Excessive nitrogen increases the discharge frequency of the gas phase kettle, increases the amount of post-treatment separation, and increases production costs. If it is directly emptied, the unit consumption of the product will increase significantly

In addition, the application of inorganic particles is mainly in post-processing modification. For example, CN1307074A and CN1150161 propose to use nanoparticles to strengthen and toughen polypropylene materials. This process requires secondary melting of polymers, and the dispersion of inorganic particles is difficult, which increases the cost of product manufacturing.

Images