Ph.Ds

Modeling and Simulations of Chemo-Mechanics of Rubber.

Research focus: Modelling and simulation of optomechanical coupling of flexible organic light emitting diodes (fOLED) responses.

Working as an external research candidate (full-time residential student for 2 semesters to complete course credits and continuing the research remotely) in the Aerospace Engineering (Structures) department, I am developing a coupled FEA model combining hyperelastic material behavior with electromagnetic wave-optics analysis. The framework predicts deformation-induced optical losses and substrate-mode propagation characteristics in PET-based fOLEDs under mechanical loading. Presented my preliminary work at the IMPLAST 2025 international conference at IIT Rookee.

Liquid crystalline elastomers (LCEs) exhibit strong coupling between mechanical deformation and orientational order, producing highly anisotropic and nonlinear mechanical responses. Classical neo-classical models typically assume affine chain deformation and fixed director length, which limits their ability to capture additional microscopic deformation mechanisms observed in experiments. In this work, a continuum framework for LCEs is developed by incorporating director microstretch and non-affine chain kinematics within a statistically derived entropic elasticity formulation.

Starting from a modified freely-jointed chain model, a probability distribution for the polymer network is derived in both reference and deformed configurations, allowing chain segments to undergo rotation and stretch along the instantaneous director. This leads to a thermodynamically consistent free energy density containing contribution coming from non-affine chain deformation. The non-affine term captures the competition between network-imposed deformation and independent director reorientation, while the semi-soft term represents the memory of the cross-linked nematic network.

The constitutive model is validated against experimental uniaxial stretching data from Zhou et al. and Higaki et al. The predicted stress–stretch behavior shows good agreement with experiments for multiple director orientations, while the model also captures the observed rotation of the director toward the stretching direction. These results demonstrate that incorporating microstretch and non-affine effects provides an improved predictive framework for modeling the coupled mechanical and microstructural behavior of liquid crystalline elastomers.