关键词:

聚甲基丙烯酸甲酯, 超临界二氧化碳, 溶胀, 在线可视测量, Sanchez-Lacombe状态方程

Abstract:

A visual measurement apparatus was applied to monitor in-situ the swelling behavior of poly(methyl methacrylate) (PMMA) in supercritical carbon dioxide(scCO₂).This work presents the swelling data of PMMA over a useful range of processing conditions (temperature from 305 K to 325 K, and pressure up to 24 MPa).The Sanchez-Lacombe equation of state (S-L EOS) is suitable to describe low molecular weight solvent-polymer systems.Through fitting the PVT data into S-L EOS, the characteristic pressure, temperature and density of PMMA were regressed as 212.38 MPa, 898.04 K and 1206.7 kg·m^-3 (8—25 MPa,305—350 K), respectively.Similarly, the characteristic parameters for carbon dioxide (CO₂) were 541.56 MPa, 313.38 K and 1502.1 kg·m^-3 (8—25 MPa,305—325 K), respectively.The equilibrium swelling data of PMMA in scCO₂ were correlated with S-L EOS, the binary interaction parameter was obtained as 1.0671.These results indicated that the S-L EOS can be used to predict the solubility of CO₂ and the swelling of PMMA over a wide range of pressure.The S-L EOS modeled values agreed well with the experimental data in supercritical region.

Key words:

聚甲基丙烯酸甲酯, 超临界二氧化碳, 溶胀, 在线可视测量, Sanchez-Lacombe状态方程