Novel epoxy-ended hyperbranched polyether derived from xylitol as sustainable tougheners for epoxy resin

Families of bio-based hyperbranched epoxy (HBPEEs) were successfully prepared using renewable xylitol, bisphenol A and epichlomhydrin as feedstocks. The structure and physical performances of HBPEEs were characterized by FTIR, NMR, GPC and viscosity evaluation. Then, they were used as high efficient tougheners for diglycidyl of bisphenol A/diethylenetriamine (DGEBA/DETA) networks. The results indicated that the incorporation of HBPEEs into the DGEBA system can significantly enhance the mechanical properties and solvent resistance properties of the hybrid (HBPEEs/DGEBA). In particular, toughened hybrids with 15 wt% HBPEE-2 exhibited the outstanding impact strength than that of neat DGEBA (37.4 kJ/m(2) vs. 11.8 kJ/m(2)) due to its excellent compatibility of with DGEBA. Simultaneously, the ductile fracture morphology of the modified hybrids was also confirmed by SEM. In addition, the activation energies of HBPEE-2/DGEBA hybrids calculated from the non-isothermal curing kinetics were lower than that of neat DGEBA. All of the results suggested that the bio-based HBPEEs could be used as efficient tougheners applied in epoxy resins industry.

Automated summary

Bio-based hyperbranched epoxy resins were prepared using renewable feedstocks and used as efficient tougheners for epoxy networks, showing significant enhancement in mechanical properties and solvent resistance. Particularly, the hybrid with 15 wt% HBPEE-2 exhibited outstanding impact strength due to excellent compatibility with DGEBA.