Structure of Model Telechelic Polymer Melts by Computer Simulation

Abstract

We present the results of molecular dynamics (MD) simulations of bead‐and‐spring models of associating polymers at melt‐like densities. Specifically, we consider telechelic (i.e., end‐functionalized) polymers of general formula AB _n A, where the A terminals tend to associate with each other and the spacer chains have length n=12,18,26. Under these conditions, the terminal groups form clusters or micelles. These are interconnected by a large fraction of bridging chains (≅70%), so that a reversible network or physical gel is formed. Depending on chain length and interaction strength among the terminals, we find that the micelles can be either quasi‐spherical or worm-like. The latter can be quite large, including 10² or more associating groups. On average, the chains are stretched compared to the unperturbed state found in the corresponding homopolymer melts.

Dedicated to Prof. John Stanford on occasion of his 60th birthday.

Keywords:

• associating polymers
• micelles
• gels
• structured fluids
• computer simulation
• molecular dynamics

Acknowledgments

The authors acknowledge financial support from the MIUR‐PRIN2003 program and the NEMAS Centre of Excellence of Politecnico di Milano.

Notes

Dedicated to Prof. John Stanford on occasion of his 60th birthday.