Tack of Entangled Molecular Bottlebrushes
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Updated: Aug 9, 2025

Nanomanipulation of Single RNA Molecules by Optical Tweezers
Published on: August 20, 2014
Carlos R López-Barrón1, Fernando Vargas-Lara1
1ExxonMobil Technology and Engineering Company, Baytown, Texas 77520, United States.
Abstract:
Polymer softness (i.e., low elastic modulus) is a known requirement for good tack in adhesives. We assess the tack performance of α-olefin molecular bottlebrushes having an elastic modulus from 4 to 30 times lower than a linear polyolefin (polypropylene). Monotonic increases of the tack parameters are observed as the bottlebrush side chain length (Nsc) increases and the modulus decreases. All-atom molecular dynamics simulations reveal that the monomeric bonding energy increases with Nsc due to a strong van der Waals interaction between the side chains and the aluminum sheet, which overcomes the energy penalty imposed by side-chain bending.
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