Hyperelasticity modeling (nanocomposite polyurea+nanotubes)

Hello,

I need to find a model for a nanocomposite (polyurea+nanotubes) in Abaqus. Given the hyperelastic behavior of this composite, I need to use the hyperelastic model in Abaqus.

I tried to model my material with an Arruda-Boyce model, but the results dont match (there is no horizontal offset, the derivative of the function is increasing). Could you help me by proposing me a method to obtaining a stress strain curve of elastomer (What are the roles of factors, what is the easiest method...)?

Please, I need your help!!

Thank you!!!

Emilien