| Abstract
| - Molecular dynamics simulations of bulk melts of poly(dimethylsiloxane) (PDMS) are utilized to study chainconformation and ordering under constant stress uniaxial extension at room temperature. We find that largeextensions induce chain ordering in the direction of applied stress. During the extension, we also find thatvoids are created via a cavitation mechanism. At the end of our simulations, by visual inspection, we distinguishcavity, fibril, and amorphous regions that coexist together. The surrounding material about the formed cavitiesis fibril-like, while the remaining material remains amorphous. We also estimate the surface energy of thecavity. The cavity size continually increases in the dimension of applied stress but saturates in the lateraldimensions, most likely due to the finite size of the system. Despite chain orientation and ordering in thedirection of applied stress, crystallization is absent in the time and stress range of our simulation. This studyrepresents a baseline for the future study of mechanical properties of PDMS melts enriched with fillers understress.
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