An effective approach for the preparation of epoxy vitrimers by in situ formation of dynamic and permanent linkages in a one-pot curing reaction

Abstract

This work reports a catalyst-free epoxy vitrimer which being prepared through one-pot thermally-induced reactions similar to the conditions applied to conventional epoxy resins. With a Meldrum’s acid functionalized aniline compound...

Inverse vulcanization employing epoxy compounds as crosslinking agents for elemental sulfur in the preparation of sulfur-rich epoxy resins

“…The measurement was interrupted at about 200 °C due to approaching the thermal degradation temperature of the sample. It is noteworthy that the T g of poly(S-MDGA-55) is higher than the values of T g for DGEBA-based epoxy resins 59 and other sulfur polymers from inverse vulcanization. 1,2,23,38,39,60 The thermal and mechanical properties of aromatic epoxy-based sulfur polymers from inverse vulcanization are attractive for extending their scope of application.…”

“…7, poly(S-MDGA-55) had a storage modulus of about 2000 MPa at 50 °C, which is comparable to the values reported for typical crosslinked epoxy resins. 59 The T g of poly(S-MDGA-55) read from tan δ could be above 197 °C. The measurement was interrupted at about 200 °C due to approaching the thermal degradation temperature of the sample.…”

“…7, poly (S-MDGA-55) had a storage modulus of about 2000 MPa at 50 °C, which is comparable to the values reported for typical crosslinked epoxy resins. 59 The T g of poly(S-MDGA-55) read…”

Biodegradable Polyester-Based Vitrimers Exhibiting Transesterification-Induced Topography Isomerization under Recycling

“…The approaches could be divided into three categories: (1) the formation of dynamic bonds in the cross-linking reaction, 4 (2) employment of precursors possessing dynamic bonds in conventional crosslinking reactions, 11,12 and (3) the simultaneous formation of dynamic and permanent covalent bonds in the cross-linking reaction. 13 On the other hand, the properties of conventional thermosetting resins, such as flame retardancy, 14,15 high glass transition temperatures, 16,17 and good mechanical properties, 18,19 should be conducted in vitrimers for practical applications. Although vitrimers exhibit thermoplastic-like recyclability, reprocessability, and sustainability, the dynamic characteristics of CANs usually bring significant creep to vitrimers.…”

“…After the first example of vitrimer possessing dynamic ester bonds, other dynamic covalent bonds have been studied and reported for the preparation of vitrimers. − The approaches to incorporate dynamic covalent bonds into the corresponding CANs also receive research attention. The approaches could be divided into three categories: (1) the formation of dynamic bonds in the cross-linking reaction, (2) employment of precursors possessing dynamic bonds in conventional cross-linking reactions, , and (3) the simultaneous formation of dynamic and permanent covalent bonds in the cross-linking reaction . On the other hand, the properties of conventional thermosetting resins, such as flame retardancy, , high glass transition temperatures, , and good mechanical properties, , should be conducted in vitrimers for practical applications.…”