Predictive Modeling of the Mechanical Properties in Triblock and Dual Triblock Copolymer Organogels

The purpose of our research is to predict the mechanical behavior of triblock and dual triblock organogels by developing a comprehensive model that is informed by a large collection of experimental mechanical property data. Block copolymer gels have applications in various sectors such as ballistics gels, model surgery materials, and are even used in transoceanic cable filler. The gels that are used in our experimentation and modeling are formulated with varying compositions of ABA triblock copolymers and aliphatic mineral oil. These gels either contain a single ABA triblock copolymer or a combination of two unique ones. We conduct quasi-static tensile tests on our formulated gels and produce nonlinear, elastic stress-extension curves. We then extract the crosslinked network and chain entanglement modulus contributions from the curves using the slip-tube network (STN) model. These modulus contributions help to describe the molecular structure within the gels, and are influenced by polymer molecular weight, "A"-block fraction, and polymer concentration. Using our experimental data and these formulation parameters, we have created an empirically-corrected STN model which allows us to predict stress-strain behavior for any triblock or dual triblock copolymer gels.