Fractal Evolving Theory and Growing Model of Olefin Polymerization Process

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Fractal Evolving Theory and Growing Model of Olefin Polymerization Process

HUO Chao^a; MENG Jun^b; REN Xiaohong^c; YANG Yongrong^c; RONG Shunxi^c

^a College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014,
China
^b Department of Electrical Engineering, Zhejiang University, Hangzhou 310027, China
^c Department of Chemical Engineering, Zhejiang University, Hangzhou 310027, China

Received:1900-01-01 Revised:1900-01-01 Online:2003-02-28 Published:2003-02-28
Contact: HUO Chao

烯烃聚合过程的分形演化及其生长模型

霍超^a; 孟灋^b; 任晓红^c; 阳永荣^c; 戎顺熙^c

^a College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014,
China
^b Department of Electrical Engineering, Zhejiang University, Hangzhou 310027, China
^c Department of Chemical Engineering, Zhejiang University, Hangzhou 310027, China

通讯作者: 霍超

Abstract

Abstract: The surface morphology of Ti-Mg supported catalyst and the polyethylene particles are
studied usingscanning electron microscope(SEM) technology. The results show that either the
catalyst’s surface or polymerparticle’s surface is irregular and has fractal
characteristics, which can be described by fractal parameter. The moreinteresting discovery
is that the surface fractal dimension values of the polymer particles vary periodically
with thepolymerization time. We call this phenomenon fractal evolution, which can be
divided into the "revolution" stageand the "evolution" stage. And then we present
polymerization fractal growing model (PFGM), and successfullydescribe and/or predict the
whole evolving process of the polyethylene particle morphology. under the different
slurrypolymerization (including pre-polymerization) conditions without H2.

Key words: polyethylene catalyst, fractal evolution theory, surface morphology, polymerization fractal growing model

摘要： The surface morphology of Ti-Mg supported catalyst and the polyethylene particles are
studied usingscanning electron microscope(SEM) technology. The results show that either the
catalyst’s surface or polymerparticle’s surface is irregular and has fractal
characteristics, which can be described by fractal parameter. The moreinteresting discovery
is that the surface fractal dimension values of the polymer particles vary periodically
with thepolymerization time. We call this phenomenon fractal evolution, which can be
divided into the "revolution" stageand the "evolution" stage. And then we present
polymerization fractal growing model (PFGM), and successfullydescribe and/or predict the
whole evolving process of the polyethylene particle morphology. under the different
slurrypolymerization (including pre-polymerization) conditions without H2.

关键词: polyethylene catalyst;fractal evolution theory;surface morphology;polymerization fractal growing model

HUO Chao, MENG Jun, REN Xiaohong, YANG Yongrong, RONG Shunxi. Fractal Evolving Theory and Growing Model of Olefin Polymerization Process[J]. .

霍超, 孟灋, 任晓红, 阳永荣, 戎顺熙. 烯烃聚合过程的分形演化及其生长模型[J]. CIESC Journal.

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