Glad to help!
Continuing on 'Epoxy Toughening' (from post #1562)
Andrew suggested that adding (any) tougheners would lower flexural on tensile modulus. I understand what rubber does, but there are other tougheners. Tests with ABS, PC and PMMA clearly show positive effect. Check out Young's modulus.
These silk-epoxy composites are tested for their mechanical properties and "it is found that the strength of the composite increases after toughening epoxy resin with ABS polymer"
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