Control of ordered block polymer structures is most commonly done via precise synthetic techniques, but blending of polymers is a significantly easier way to control structures if the process can be understood. We will blend AB and C-D block copolymers to create interesting and useful morphologies such as self-coating films (where one block presents itself at a free interface), or combinations of known morphologies.
Nanoparticles may be added to polymers to improve mechanical, thermal, or optical properties of the resulting nanocomposite, but precise control over nanoparticle arrangement and interfacial state is necessary for these systems to reach their ultimate potential. We will use the natural propensity of block copolymers to microphase separate to control the arrangement and interfacial properties in these dispersions. We will perform these studies via molecular dynamics because such simulations are adept at exploring such properties and systems.
Molecular dynamics simulations of polymeric systems are significantly limited in terms of the time and length scales that can be studied. We will develop a new technique, Protracted Colored Noise Dynamics for Polymer Systems (PCND), which applies a time correlated random force in order to increase phase space sampling and reduce time to equilibration. Our preliminary results indicate that a 4 order of magnitude decrease in defect annihilation time is achievable. We will adapt this technique to a variety of polymer architectures and models, allowing access to timescales far beyond current capabilities.