Properties of Reversible Diels–Alder Furan/Maleimide Polymer Networks as Function of Crosslink Density

Thermally reversible thermosets are synthesized based on furan functionalized polyketones crosslinked with (methylene-di-p-phenylene)bis-maleimide. The number of furan groups present along the backbone and the crosslinker/furan molar ratio are varied. According to DSC measurements the de-crosslinking temperature does not change signifi cantly as function of furan intake and its molar ratio with the crosslinker. All samples show an almost complete recovery of storage and loss modulus. The crosslinked samples are recycled up to seven times without signifi cant quality loss. This suggests that a change in conformation does not result in different visco-elastic behavior. The most crosslinked sample is able to fully repair itself within 1 hour. A number of low crosslink density materials additionally show a shape memory effect.