Reaction kinetics and thermodynamic aspects of thermoreversibly cross-linked polymer networks

The Diels-Alder reaction of furan and maleimide is used to prepare reversibly cross-linking polymer gels consisting of furan-bearing polymer chains and bismaleimides. The roles of chain length, stoichiometry, and concentration on gelation kinetics and other properties are evaluated. Additionally, kinetics of the Diels-Alder reactions in the gelling system are compared with the kinetics of small molecule systems. By combining spectroscopic and rheological techniques, a mechanochemical analysis is performed. Furan-bearing polymer chains are cross-linked in solution by bismaleimides through a thermoreversible Diels-Alder reaction. The roles of chain length, stoichiometry, and concentration on gelation are evaluated. By combining spectroscopic and rheological techniques, mechanochemical analysis is performed, which demonstrates that the relationship between modulus and number of cross-links can be described by traditional gel elasticity theory.