Polymer Plasticization Using Supercritical Carbon Dioxide: Experiment and Modeling

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• 作者：I. Kikic ; F. Vecchione ; P. Alessi ; A. Cortesi ; F. Eva ; and N. Elvassore
• 刊名：Industrial & Engineering Chemistry Research
• 出版年：2003
• 出版时间：June 25, 2003
• 年：2003
• 卷：42
• 期：13
• 页码：3022 - 3029
• 全文大小：139K
• 年卷期：v.42,no.13(June 25, 2003)
• ISSN：1520-5045

文摘

The most important effect of sorption of compressed gases and supercritical fluids into glassypolymers is the reduction of the glass transition temperature (T_g). This plasticization effect causeschanges in mechanical and thermophysical properties of the polymers. In this work, athermodynamic study based on experimental and theoretical results is addressed. New datawere carried out for poly(2,6-dimethylphenylene oxide) (PPO), poly(acrylic acid) (PAA), and thecopolymer vinylpyrrolidone-vinyl acetate [P(VP-VA)] using an inverse gas chromatographictechnique. To model the T_g behavior of diluent-polymer systems, a model that couples the lattice-fluid equation of state and the Gibbs-DiMarzio criterion was used. A parametric study of theinfluence of the physical properties (lattice coordination number, molecular weight, and binaryinteraction parameter) on the T_g behavior is presented. The thermodynamic model fairly describesthe experimental data measured in this work and gives a phenomenological representation ofthe retrograde vitrification for the systems PPO-CO₂, PVP-CO₂, and P(VP-VA)-CO₂.