Viscoelasticity of Chemically Bonded Interfacial Epoxy-Polyurea Matrix per Migration of Epoxy Species via Curing Time Parameter
A new fiber (x) reinforced Dynamic Covalent epoxy-polyurea Interface (x-DCEPI) shows good mechanical energy transferability of impact and vibration forces. The bonding property of x-DCEPI interface, engendered between curing, or reactive, epoxy and dynamic polyurea, is controlled by epoxy curing time (tc). The reaction of curing epoxy, where tc is a thermodynamic processing parameter, and fast-curing/ dynamic aliphatic polyurea, which lacks polyol in its resin chain extender, is linked to bulk mechanical energy transfer, quantified specifically via the loss modulus of x-DCEPI. The parameter tc effectuates designable chemical bond properties within x-DCEPI. Using Generalized Maxwell models, viscoelastic properties of epoxy, polyurea, and x-DCEPI are predicted, and results are verified using Dynamic Mechanical Analysis (DMA). The Maxwell models for x-DCEPI, as a function of tc, are used in a finite element analysis (ABAQUS) to control performance of dynamically loaded structures.
L. He and T. L. Attard, "Viscoelasticity of Chemically Bonded Interfacial Epoxy-Polyurea Matrix per Migration of Epoxy Species via Curing Time Parameter", Key Engineering Materials, Vol. 779, pp. 71-79, 2018