Research (building)

The MS2M = Mechanics of Smart and Soft Materials Lab focuses on the mechanical behavior of smart and/or soft materials, mostly polymers and elastomers. However, this class of materials also encompasses biological materials and soft tissues.  Specifically, we are interested in the underlying mechanisms leading to their macroscopic behavior. We investigate the time-dependent and temperature-dependent mechanical behaviors of smart and soft materials in order to develop reliable theoretical models.

Materials are referred to as smart to emphasize that they can respond mechanically to an external stimulus, such as temperature or light. Within this class of materials, smart elastomers are particularly attractive since the polymer network provides a stable and shapable matrix for active components. Active elements are directly chemically integrated to the network, such as crystal-forming mesogens, or physically added, such as a percolated network of magnetic iron particles. The added elements affect the mechanical behavior of the polymer network, while the chemical links and viscosity of the network constrain the active elements, thus influencing their actuation. The ability to predict the effective behavior of smart polymers is key to the generation of numerically-based design tools and to the optimization of multifunctional devices. 

The research combines experimental investigations with modeling approaches to understand and predict the nonlinear behavior of these materials. Active polymers present a modeling challenge because the actuation results from the coupling between at least two physical mechanisms. The small scale mechanisms, such as polymer chain dynamics, swelling, actuation, and ageing, result in the observed nonlinear behavior. Understanding the mutual interactions between these mechanisms governs the quality of the theoretical models. The lab is also interested in exploring innovative applications for liquid crystal elastomer, using new manufacturing methods and synthesis routes applicable to soft materials.

Current Research Projects

Liquid Crystal Elastomers

  • Modeling soft elasticity of liquid crystal elastomers
  • 4D printing of liquid crystal elastomers
  • Heterogeneous orientation in liquid crystal elastomers
  • Damping in Liquid Crystal Elastomers
  • Time-temperature Superposition in Liquid Crystal Elastomers
  • Liquid Crystal Elastomer Fibers

Biomechanics

  • A smart skin for pressure ulcers
  • Biomechanics of pregnant women
  • Musculoskeletal modeling and obesity
Previous Research Projects

Viscoelastic phenomena in Roll-to-Roll processing:

  • Viscoelastic Poisson’s ratio in webs for roll-to-roll processing
  • Viscoelasticity in roll-to-roll lamination
  • Viscoelasticity and curing phenomena in roll-to-roll nano imprint lithography

Micromechanical modeling of UHMWPE fibers

Statistical Mechanics of a Polymer Chain

Solid Propellant: a highly-filled elastomer