Pivot Algorithm and Push‐off Method for Efficient System Generation of All‐Atom Polymer Melts: Application to Hydroxyl‐Terminated Polybutadiene

Abstract

Procedures used to generate initial conditions for all‐atom molecular dynamics (MD) simulations of amorphous polymer systems are described. The pivot algorithm is applied directly to produce unbranched hydroxyl‐terminated cis‐1,4‐polybutadiene molecules with chain lengths ranging from 8 to 64 monomeric units (32 to 256 carbon atoms), based on the OPLS all‐atom force field. The generated molecular configurations are characteristic of (pseudo‐) ideal conditions and therefore exhibit the same properties as polymer chains in a melt. We analyze both the mean squared chain dimensions and their distributions in order to validate the correctness of this approach. The chains are efficiently packed into 3d‐periodic simulation cells using the push‐off method and subsequently equilibrated by standard MD. Together, the pivot algorithm and push‐off method provide the means for efficient generation of equilibrated dense polymer melts for multi‐million‐atom systems.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jun 27, 2013
Source ID
10.1002/mats.201300103

Entities

People

  • Markus G. Fröhlich
  • Thomas D. Sewell

Organizations

  • Defense Threat Reduction Agency
  • University of Missouri

Tags

Fields of Study

  • Chemistry

Readers

  • Computational Modeling and Simulation
  • Materials Science and Engineering.
  • Polymer Science and Technology