Mechanistic insights on nanosilica self-networking inducing ultra-toughness of rubber-modified polylactide-based materials

AbstractDeveloping novel strategies to improve the impact strength of PLA-based materials is gaining a significant importance in order to enlarge the range of applications for this renewable polymer. Recently, the authors have designed ultra-tough polylactide (PLA)-based materials through co-addition of rubber-like poly(ϵ-caprolactone-co-d,l-lactide) (P[CL-co-LA]) impact modifier and silica nanoparticles (SiO2) using extrusion techniques. The addition of silica nanoparticles into these immiscible PLA/P[CL-co-LA] blends altered their final morphology, changing it from rubbery spherical inclusions to almost oblong structures. A synergistic toughening effect of the combination of P[CL-co-LA] copolymer and silica nanoparticles on the resulting PLA-based materials therefore occurred. To explain this particular behavior, the present work hence aims at establishing the mechanistic features about the nanoparticle-induced impact enhancement in these immiscible PLA/impact modifier blends. Incorporation of silica na...