Adsorption of active polymers on attractive nanoparticles

• Published in: Soft matter 2024-01, Vol.2 (3), p.621-628
• Main Authors: Shen, Yi-Fan, Hu, Han-Xian, Luo, Meng-Bo
• Format: Article
• Language: English
• Subjects: Adsorption; Conformation; Lennard-Jones potential; Nanoparticles; Polymers; Rotation; Tails
• ISSN: 1744-683X; 1744-6848
• DOI: 10.1039/d3sm01380d

The adsorption of active polymers on an attractive nanoparticle (NP) is studied using Langevin dynamics simulations. The active polymers consist of an active Brownian particle (ABP) at the head and a subsequent passive polymer chain. The ABP experiences an active force of magnitude F a . The interactions between the active polymer and NP are modeled as Lennard-Jones potential with a strength pn . We find the critical adsorption point pn * increases with increasing the active force F a . The increment of pn *, denoted as Δ pn *, due to F a can be expressed approximately as Δ pn * ∝ F a 2.5 for the restricted rotating active polymer (RRAP) where the rotation of the head ABP is restricted and Δ pn * ∝ F a 1.7 for the freely rotating active polymer (FRAP) where the ABP rotates freely. Meanwhile, the conformation of the adsorbed polymer, such as adsorbed trains on NP and the tail near the ABP, are also dependent on F a . When the tail near the ABP is short, the adsorption is significantly affected by the active force. However, when the tail is long, the whole polymer can be viewed as a long tail stretched by the active force and unperturbed adsorption monomers. Simulation results show that the active force has a direct and significant effect on pn * and the structure of the adsorbed active polymers. The critical attraction strength for the adsorption of active polymers on nanoparticles increases with the active force. It becomes more sensitive to the length of the polymers under the action of active force.