Particle movement characteristics in a gas–solid vertical single helical ribbon agitated reactor

Reducing the Surface Stickiness of Multiphase Polypropylene Particles: An Environmentally Friendly and Scalable Method

“…Multiphase polypropylene, which has been widely used for its excellent overall performance, , is a multiphase and multicomponent in-reactor alloy prepared by two-stage polymerization, including the bulk polymerization of propylene and the subsequent gas-phase copolymerization of ethylene and propylene. , The ethylene–propylene rubber is produced directly in the primary particles of isotactic polypropylene, resulting in good dispersion of the particles. − Polypropylene resins with a rubber content of less than 25 wt % are feasible to make in ordinary polypropylene plants, whereas resins with a rubber content of more than 25 wt % are not. , Although certain polypropylene factories claim to be able to manufacture up to 50 and 70 wt % of rubber using the Horizone process and Catalloy technology, respectively, these technologies rely on a combination of multiple reactors in series and high-porosity catalysts and are prone to encounter particle stickiness problems. This is because low copolymerization activity after the propylene homopolymerization is a common issue in manufacturing polypropylene resins with a high rubber content. , More importantly, as the rubber content increases, sticky particle surfaces gradually appear, triggering agglomeration in the reactor and lowering the production stability, which is a major restriction in the manufacture of polypropylene resins with a high rubber content …”

“…This is because low copolymerization activity after the propylene homopolymerization is a common issue in manufacturing polypropylene resins with a high rubber content. 9,10 More importantly, as the rubber content increases, sticky particle surfaces gradually appear, triggering agglomeration in the reactor and lowering the production stability, which is a major restriction in the manufacture of polypropylene resins with a high rubber content. 11 From a process standpoint, one would like to be able to regulate the amount of rubber in the particle 12 (typically as high as possible) to fulfill the required properties of the final product without experiencing substantial reactor operational issues.…”