Abstract
Poly(styrene-b-dimethylsiloxane-b-styrene) (PS-PDMS-PS) triblock copolymers were prepared by anionic polymerization and subsequently hydrogenated using a platinum/rhenium catalyst supported on ultrawide pore silica (Pt/Re - SiO 2), yielding PCHE-PDMS-PCHE, where PCHE refers to poly(cyclohexylethylene). The hydrogenation reaction resulted in polymer with negligible chain degradation as confirmed by 1H NMR and size exclusion chromatography (SEC). Small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM) experiments revealed a lamellar morphology for all specimens. Thermodynamic properties were inferred from the order-disorder transition temperatures as determined by SAXS and dynamical mechanical spectroscopy (DMS). The resulting segment-segment interaction parameter, x(T), is assessed in the context of current published approaches to treating the thermodynamics of nonpolar polyolefins, particularly block copolymers.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 6638-6646 |
| Number of pages | 9 |
| Journal | Macromolecules |
| Volume | 40 |
| Issue number | 18 |
| DOIs | |
| State | Published - Sep 4 2007 |
Bibliographical note
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