Spherulite boundary strengthening concept for toughening polypropylene

Effects of processing route on morphology and mechanical behavior of polypropylene in equal channel angular extrusion

“…4). Previous observations of crack initiation and propagation through centers and boundaries of spherulites indicate that these are sites of weakness in spherulites of iPP, often resulting in premature mechanical failure 40–44. According to this view, the inclination of the crack further confirms the deformation of spherulites in ECAE‐deformed samples.…”

Morphological structure, thermal and mechanical properties of tough poly(lactic acid) upon stereocomplexes

“…There have been a considerable number of investigations to toughen PLA with the goal of balancing and increasing tensile strength, impact strength and elongation at break while retaining the biocompatible and biodegradable nature by the introduction of a rubbery phase in block copolymers and blends [3][4][5][6]. One example of toughening is to blunt the sharp tip of crack propagation [7]. Improvements can involve alteration of interface (e.g.…”

Dynamic Mechanical and Thermal Properties of Modified Poly(propylene) Wood Fiber Composites

“…With addition of maleated poly(propylene) this lower temperature peak disappears as can be seen in Figure 3. It could be speculated that the second phase might have preferentially been located where the polymer is weakest, connecting adjacent spherulite boundaries through co‐crystallization,39 which would be a probable reason for the toughening effect of maleated PP on the PP matrix.…”