Role of graded length side chains up to 18 carbons in length on the damping behavior of polyurethane/epoxy interpenetrating polymer networks

- Introduction of graded length side chains improved significantly the damping peak of PU/EP IPNs.
- The damping temperature range depended on the interaction between the side chain and PU segments not the side chain length.
- The side chain with ester group enhanced H-bond interaction within the hard segments.
- The IPNs with side chain carrying ester group exhibited microphase separation structure with relatively large-sized domain.
- The mechanical properties of IPNs were significantly affected not by the side chain length but by the side chain content.