COMPARATIVE STUDY OF MECHANOCHEMICAL SCISSION RATE OF LINEAR AND CYCLIC POLYMERS

Mechanical force applied to polymeric materials leads to physical and chemical changes in the polymer chains.¹ When enough mechanical force is accumulated, a covalent bond in the polymer chain undergoes scission, leading to decreased molecular weight.^2,3 While the mechanochemical reactions and materials’ physics have been abundantly studied, the use of polymer architecture as a motif for polymer mechanics has been mostly unexplored given the difficulties of precise architecture control in large polydisperse structures. Here, we study the effect polymer cyclization has on the mechanochemical dispersion of mechanical force, comparing homo cyclic polymers and linear polymers of same monomer chemistry. For this purpose different linear and cyclic polymers of a range of molecular weights have been synthesised via ring-opening and ring-expansion methathesis polymerization.

Reference:

1. Stevens, M. P. Polymer Chemistry: An Introduction, 3rd ed.; Oxford University Press: New York, 1999.
2. B. A. Buchholz, J. M. Zahn, M. Kenward, G. W. Slater and A. E. Barron, Polymer, 2004, 45, 1223.

M. M. Caruso, D. A. Davis, Q. Shen, S. A. Odom, N. R. Sottos, S. R. White and J. S. Moore, Chem. Rev., 2009, 109, 5755.