Mixed monolayers of polymethyl methacrylate and polyethyl methacrylate at several temperatures

2012

The objective of this research was to find out the effect of molecular weight of poly(methyl methacrylate) (PMMA) and temperature on the isobaric relaxation behaviors of mixed PMMA/poly(styrene)-block-poly(ethylene oxide) (PS-b-PEO) monolayers. Isobaric relaxation experiments of mixed monolayers of PMMA with different molecular weights and PS-b-PEO at the air/water interface were investigated at three different temperatures (10, 25, and 40 C). The PS-b-PEO monolayer was found to exhibit a fast relaxation curve (i.e., the surface area decreased significantly with increasing time). Addition of PMMA into PS-b-PEO slowed the relaxation behavior especially at the lowest experimental temperature (10 C). It was shown that the area relaxation process of mixed PMMA/PS-b-PEO monolayers could be well represented by a model considering the nucleation and growth mechanisms. The characteristic exponent x values were found to be almost temperature independent. The k x values were detected to decrease mostly as a result of temperature elevation regardless of pure or mixed monolayers. V C 2012 Wiley Periodicals, Inc. J Appl Polym Sci 126: E267-E274, 2012

Section: Introductionmentioning

confidence: 99%

Isobaric relaxation phenomenon of mixed PMMA/PS‐b‐PEO monolayers at different temperatures

Jheng

2012

“…He also proposed conformations for the ester groups in these materials at the air‐water interface, on the basis of measurements of the dipole moments. Since then many articles have been published about PMMA monolayers at the air‐water surface, such as its monolayer miscibility with low molecular weight substances and other polymers, the stability and hysteresis that may occur3–6 and so on.…”

Section: Introductionmentioning

confidence: 99%

Characteristics and iso‐baric relaxation phenomenon of pmma monolayers with different molecular weights at different temperatures

Jheng

2010

Poly(methyl methacrylate) (PMMA) monolayers with different molecular weights at the air/water interface were investigated at three different temperatures. The monolayer characteristics of PMMA were studied in terms of surface pressure-area per molecule (p-A) isotherm and isobaric relaxation experiments. The results show that the p-A isotherms of PMMA converge at 40 C regardless of molecular weight. The collapse pressure of PMMA monolayers decreases as the temperature is elevated. It was shown the area relaxation process of PMMA could be described by a model considering the nucleation and growth mechanisms. The simulation parameters of area relaxation of PMMA with different molecular weights at 8 mN/m are very similar, indicating similar mechanisms.

“…He also proposed conformations for the ester groups in these materials at the air–water interface, based on measurements of the dipole moments. Since then a lot of articles have been published about PMMA monolayers at the air–water surface, such as its monolayer miscibility with low molecular weight substances and other polymers, the stability and hysteresis that may occur,3–6 and so on.…”

Section: Introductionmentioning

confidence: 99%

Relaxation phenomena of stereoregular poly(methyl methacrylate) monolayers at the air/water interface

Lee

2007

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 pressurearea per molecule (p-A) isotherm, area relaxation, and pressure relaxation. The results show that pressures at inflection points of p-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.