Modeling the solubility of ternary mixtures of ethylene, iso-pentane, n-hexane in semicrystalline polyethylene

✍ Scribed by Wenjuan Yao; Xiaoping Hu; Yongrong Yang

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 519 KB
• Volume: 104
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.26137

✦ Synopsis

The coabsorptions of ethylene and iso-pentane, and ethylene and n-hexane were measured by the use of a pressure decay method. The solubility data of ethyleneiso-pentane and ethylene-n-hexane in semicrystalline polyethylene (PE) of crystallinity of 48.6% were obtained at temperatures 70, 80, and 90 8C, and the total pressure 2 MPa, iso-pentane partial pressure 80-190 KPa, n-hexane partial pressure 20-90 KPa. The presence of iso-pentane or n-hexane in the corresponding ternary system leads to increase the solubility of ethylene, while the solubility of iso-pentane or n-hexane remains unchanged with an increase of the ethyl-ene partial pressure, even slightly decreases. Assumed that the presence of iso-pentane or n-hexane decreases the crystallinity of the polymer sample, a coabsorption model was built to model the solubility of each gas in the ternary systems. The relative root mean square errors of the coabsorption model for ethylene-iso-pentane-PE system and ethylene-nhexane-PE system are 5.13% and 4.64%, respectively.