Effect of Hydrophilic- and Hydrophobic-Chain Lengths on the Phase Behavior of A−B-type Silicone Surfactants in Water
| Autor: | Makiko Horii, Asao Harashima, and Haruhiko Furukawa, Md. Hemayet Uddin, Hironobu Kunieda |
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| Rok vydání: | 2001 |
| Předmět: |
Materials science
Small-angle X-ray scattering Hexagonal phase Surfaces Coatings and Films Crystallography chemistry.chemical_compound Silicone Surface-area-to-volume ratio chemistry Pulmonary surfactant Liquid crystal Phase (matter) Polymer chemistry Materials Chemistry Lamellar structure Physical and Theoretical Chemistry |
| Zdroj: | The Journal of Physical Chemistry B. 105:5419-5426 |
| ISSN: | 1520-5207 1520-6106 |
| DOI: | 10.1021/jp003314h |
| Popis: | The phase behavior of a long hydrophobic chain A−B-type silicone surfactant, Me3SiO−(Me2SiO)m-2−Me2SiCH2CH2CH2−O−(CH2CH2O)nH (Sim C3EOn), in water was investigated by phase study and small-angle X-ray scattering (SAXS). The types of liquid crystals or self-organized structures are highly dependent on both EO-chain (n) and poly(dimethylsiloxane)-chain (m) lengths or the volume ratio of the EO chain to the total surfactant, nVEO/VS, which is related to the classical Griffin's HLB value. Reverse discontinuous cubic phase (I2) for Si14C3EO7.8 and Si25C3EO7.8,12.2,15.8, reverse hexagonal phase (H2) for Si14C3EO12, lamellar (Lα) phase for Si14C3EO15.8 and Si25C3EO51.6, and hexagonal (H1) and discontinuous cubic (I1) phases for Si5.8C3EO36.6,51.6 are formed. Hence, both hydrophobic and hydrophilic chains affect the surfactant layer curvature, but in an opposite way. On the other hand, the effective cross-sectional area per surfactant at the hydrophobic surface of self-organized structures, aS, increases with inc... |
| Databáze: | OpenAIRE |
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