Relaxation phenomena of stereoregular poly(methyl methacrylate) monolayers at the air/water interface |
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Authors: | Yuh‐Lang Lee Wen‐Ping Hsu |
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Affiliation: | 1. Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan 70101, Republic of China;2. Department of Chemical Engineering, National United University, Miao‐Li, Taiwan 36003, Republic of China |
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Abstract: | Relaxation behaviors of isotactic, atactic, and syndiotactic poly(methyl methacrylate) (PMMA) monolayers at the air/water interface were investigated at three different temperatures. The monolayer characteristics of the three stereoisomers were studied in terms of surface pressure–area per molecule (π‐A) isotherm, area relaxation, and pressure relaxation. The results show that pressures at inflection points of π‐A isotherms of PMMA decrease with an increase in temperature. The collapse pressure also decreases as the temperature is elevated. It was shown likely for the first time that the relaxation process of PMMA stereoisomers could be described by a model considering the nucleation and growth mechanisms. The simulation parameters of area relaxation of the three stereoisomers at 30 mN/m are very similar, indicating similar mechanisms. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 |
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Keywords: | relaxation stereoregular PMMA monolayer |
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