Thermal Breakdown by the Retro Diels–Alder Reaction of Crosslinking in Poly[styrene‐co‐(furfuryl methacrylate)]

Abstract

Crosslinked poly[styrene‐co‐(furfuryl methacrylate)] has been produced by the Diels–Alder (D‐A) reaction between the furan ring (within the copolymer) and the maleimide (MI) group (within the other reactant, bismaleimide). The retro D‐A reaction was followed by the analysis of MI groups produced at different times at five constant temperatures. The process was shown to follow first‐order kinetics, and the rate constants were determined. The findings are believed to be the first to provide quantitative information on the breakdown by a retro D‐A reaction of crosslinking in a polymer system. The D‐A and retro D‐A processes constitute a thermoreversible gelling system with respect to the formation and breakdown of crosslinks.First‐order rate plot for the retro D‐A breakdown of crosslinked poly(ST‐co‐FM).magnified imageFirst‐order rate plot for the retro D‐A breakdown of crosslinked poly(ST‐co‐FM).

Epoxy‐amine based thermoresponsive networks designed by Diels–Alder reactions

“…Generally, different methods have been adopted for the synthesis of crosslinked materials using the DA reaction. It can be applied either between multifunctional diene and multifunctional dienophile grafted polymers, or between a small multifunctional diene or dienophile molecule with a polymer bearing diene or dienophile moieties . For instance, Goiti et al synthesized networks from a small bis‐dienophile molecule and a styrene‐furfuryl methacrylate copolymer and studied the crosslinking reaction by UV spectroscopy.…”

Thermoreversible cross-linking of maleated ethylene/propylene copolymers with diamines and amino-alcohols

“…DielseAlder reactions between furan and maleimide groups [4,5] and between two cyclopentadiene groups [6,7] have been successfully used for thermoreversible crosslinking of polymers. Urethane formation from isocyanate and hydroxyl groups is also thermoreversible [8,9] and has been used for polymer cross-linking [10,11].…”

Investigation on the thermal properties of new thermo-reversible networks based on poly(vinyl furfural) and multifunctional maleimide compounds

“…The reversibility of DA reaction is widely applied to the preparation of remarkable polymers. Thermallyreversible DA reactions have been used in numerous studies including polymer synthesis from multifunctional monomers [4,[7][8][9][10][11][12][13][14][15] or by cross-linking of functional copolymers containing maleimide or furan pendant groups [16][17][18][19][20][21][22], surface modifications [16,23], organic-inorganic polymer hybrids [24,25], reversible crosslinking polymer chains/ gels [5,16,24,26] and remendable/self-healing polymers [11,12,27]. Due to the fact that these reactions can proceed under mild conditions without a catalyst, this makes them attractive for designing covalently reversible bonds in which furan and maleimide functional groups are responsible for association and dissociation [28][29][30][31].…”