Method for continuously producing ultra-high molecular weight polyethylene by using slurry polymerization

• Main Authors: CHEN, MING-HUA, XIA, HUI-MIN, GUO, FENG, CHEN, SHAO-HUI, YANG, LIU, XING, YUE-JUN, ZHAI, JIAN-HONG, LI, CHUAN-FENG, YOU, ZHONG-LIN, WANG, WEN-RUI, JING, KUN, TU, SONG-TAO
• Format: Patent
• Language: Chinese; English
• Published: 16.08.2022
• Subjects: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; THEIR PREPARATION OR CHEMICAL WORKING-UP; THEIR RELEVANT APPARATUS; TRANSPORTING

The present invention relates to a method for continuously producing ultra-high molecular weight polyethylene by using ethylene slurry polymerization. An ultra-high molecular weight polyethylene having a viscosity average molecular weight of 1.5 to 8 million g/mol can be continuously produced under conditions of ethylene slurry polymerization in an atmosphere without hydrogen by using a series mode of 2-6 ethylene slurry polymerization reaction kettles, controlling the deviations of the polymerization temperature, polymerization pressure and gas phase composition between said kettles within certain ranges, and performing continuous slurry polymerization of raw materials comprising ethylene and optionally a comonomer. The polymerization method is flexible, and has a large control margin, and the polymer has stable properties. Furthermore, the obtained ultra-high molecular weight polyethylene has a low metal content, a low ash content, and excellent mechanical properties.