Molecular Stress Relief through a Force-Induced Irreversible Extension in Polymer Contour Length

作者：Wu Dong; Lenhardt Jeremy M; Black Ashley L; Akhremitchev Boris B^*; Craig Stephen L

来源：Journal of the American Chemical Society, 2010, 132(45): 15936-15938.

DOI：10.1021/ja108429h

Single-molecule force spectroscopy is used to observe the irreversible extension of a gem-dibromocyclopropane (gDBC)-functionalized polybutadiene under tension, a process akin to polymer necking at a single-molecule level. The extension of close to 28% in the contour length of the polymer backbone occurs at roughly 1.2 nN (tip velocity of 3 mu M/S) and is attributed to the force-induced isomerization of the gDBCs into 2,3-dibromoalkenes. The rearrangement represents a possible new mechanism for localized stress relief in polymers and polymer networks under load, and the quantification of the force dependency provides a benchmark value for further studies of mechanically triggered chemistry in bulk polymers.

• 出版日期2010-11-17