Toughening model of filled thermoplastic vulcanizates with dual-phase continuity

Polylactic acid/natural rubber/silicon dioxide thermoplastic vulcanizate with balanced stiffness-toughness had been fabricated in our previous work. To further elucidate the excellent impact strength of the co-continuous thermoplastic vulcanizate, a toughening model of the thermoplastic vulcanizate is established by imitating fiber distance theory in steel fiber reinforced concrete structure, which has a similar co-continuous structure. In addition, the other factors, such as the strength of the rubber phase and the interfacial adhesion between the two phases, are adopted to modify the model, which also have an intimate connection with the toughness of the composites. A quite good fit with Adj. R-Square of 0.94 is accepted. The construction of this model not only deepens the comprehension of toughening mechanism, but also provides a wind indicator for designing the super-tough composites with a co-continuous structure.