Table 2

Summary of healing efficiencies for the three WCl6 delivery methods and the effect of coupling agent on fracture toughness.

sample typeno. of samplesWCl6 loading (wt%)coupling agent (wt%)Embedded Imagevirgin (MPa.m1/2)Embedded Imagehealed (MPa.m1/2)η (%)η′ (%)
neat resin8000.84±0.06
neat resin8010.85±0.08
as-received5700.44±0.110.20±0.0946187
as-received61200.44±0.030.47±0.07107263
as-received41210.67±0.140.52±0.1478247
recrystallized74.410.55±0.10NLb11
recrystallized4700.37±0.040.17±0.0446160
recrystallized71200.41±0.060.37±0.1290231
recrystallized51210.66±0.090.44±0.0967204
wax protecteda44.400.60±0.05NLb49
in situc31200.85±0.06NLb20
  • a 20 wt% wax beads in epoxy resin with 22 wt% WCl6 concentration in wax.

  • b NL, nonlinear healing response.

  • c 15 wt% microcapsules of exo-DCPD/phenylacetylene/nonylphenol.