| Autor: |
Sakae, Shuji, Takayama, Shigeki, Yamasaki, Terumasa |
| Předmět: |
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| Zdroj: |
Kobunshi Ronbunshu; 2004, Vol. 61 Issue 5, p315-322, 8p, 3 Diagrams, 2 Charts, 8 Graphs |
| Abstrakt: |
Styrene-butadiene block copolymer (SBS) is a typical thermoplastic elastomer that is widely used for various applications. An inherent problem with this polymer is thermal degradation, since it contains double bonds. There are many studies on this issue, but still it is not quantitatively understood how facile the 1,2-bond and the 1,4-bond are, respectively, toward the hydrogen abstraction reactions and toward the thermal degradation of the polymer. In our previous work, we reported that 1,2-bond contributes more to the gel formation than the 1,4-bond does. Here we present the effects of both types of bonds on the gel formation by using quantum chemical calculations and kinetic simulation approaches. The result shows that the hydrogen is slightly easier to be extracted at the 1,2-bond moiety over the 1,4bond; such a small difference can cause greater consequences for the thermal stability in the course of the propagation reactions with oxygen molecules. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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