Capillary wave investigation of surface films of diblock copolymers on an organic subphase. Poly(dimethylsiloxane)-Poly(styrene) films at the air/ethyl benzoate interface

Journal Article · Wed Jun 01 00:00:00 EDT 1994 · Langmuir; (United States)

DOI:https://doi.org/10.1021/la00018a056· OSTI ID:7102078

Runge, F E; Yu, H ^[1]; Kent, M S ^[2]

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1. Univ. of Wisconsin, Madison, WI (United States)
2. Sandia National Lab., Albuquerque, NM (United States)

The surface film viscoelastic properties of poly(dimethylsiloxane) (PDMS) homopolymers and several poly(dimethylsiloxane)-poly(styrene) (PDMS-PS) diblock copolymers at the air/ethyl benzoate (A/EB) interface have been examined by surface quasi-elastic light scattering (SLS) as a function of surface pressure, II, determined with the Wilhelmy plate technique. All systems used in this study form stable, but to some extent, soluble monolayers at A/EB. The advantage of SLS is that it gives reliable dynamic film elasticities and viscosities even in a situation where the static elasticities cannot be determined by standard methods. Relative to the values for PDMS homopolymers at the same II, increases in both the surface dilational elasticity, [epsilon][sub d], and the corresponding viscosity, [kappa], for the diblock copolymers are observed for all copolymer samples. The deviations occur at much lower surface pressures for the asymmetric copolymers (higher PS content) than for a nearly symmetric sample. This suggests that the symmetric sample interacts mainly via the surface PDMS blocks, while the highly asymmetric samples interact mainly through the submerged PS blocks. The magnitudes of [epsilon][sub d] and [kappa] for the copolymers obtained in this study are consistent with the picture of relatively flexible, submerged PS blocks. 32 refs., 10 figs., 2 tabs.

• DOE Contract Number: AC04-94AL85000
• OSTI ID: 7102078
• Journal Information: Langmuir; (United States), Vol. 10:6; ISSN 0743-7463
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE
COPOLYMERS
MECHANICAL PROPERTIES
FILMS
SILICONES
AIR
COMPILED DATA
ELASTICITY
ESTERS
LIGHT SCATTERING
PRESSURE MEASUREMENT
VISCOSITY
DATA
FLUIDS
GASES
INFORMATION
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC POLYMERS
ORGANIC SILICON COMPOUNDS
POLYMERS
SCATTERING
SILOXANES
TENSILE PROPERTIES
400201* - Chemical & Physicochemical Properties
360603 - Materials- Properties
360606 - Other Materials- Physical Properties- (1992-)